I'm sure it's a good idea. but I have about an average attention span of about an hour. when it comes to electronic fuel injection it is more reliable. but if an issue happens with the ECU (the main computer) for all the engine management. out on the trails there is virtually no fix that can be done. because the micro circuit transistorized components in the ECU. there no fix only replacement but ECU failure is extremely rare. I was always tought that when reading spark plugs. the ideal color for the plugs should be a chocolate brown color. and you have to remember that snowmobiles are normally operated in colder ambient temperatures. and that would explain the lean idling condition. because lean engines always run hotter. and rich engines always run cooler. so in the hotter ambient temperatures you would want the engine to run richer.
Yep. Keep it. Learn to dial it in. It is good knowledge to have. Props to Brian for the troubleshooting and back and forth. That thing is a sick little ripper!
160 is overheat on a sled in winter you need to leave the fan on. My sled runs at 100 in the snow all day long. You need a baffles in the gas tank that's why you are running out of gas on hard corners imo. Great show tho man 👍.We lay sles on there sides and do powder turns all day on sleds with carbs and they dont bog down
The O2 sensor is on a bad spot. Try moving it a bit further into the narrower part or even the small pipe piece after the expansion chamber. Where it stands now it will only read a fraction of the gases. That´s why u´re getting a false reading. It doesn´t matter if it´s a 2 or a 4 stroke, the O2 sensor has to be mounted where it can read the most ammount of exaust gases possible. Hope this helps u get a better tunning. Doesn´t matter if it´s a bike, a snowmobile or a car. The principle is the same regarding O2 sensors. About the third jet, it´s a power jet. It´s main objective is to compensate for the lack of fuel at higher RPM. With those carbs u can finetune idle, mid range and high RPM seperately to get the most power out of the full range of the engine. Love your vids. Have fun and keep hustling. 🦾
Hey Chris 🙂 When its starved after the donuts, and you almost can't start it again, it tells me that the floats are empty, and its not a "slushing" problem. I would look to replace the pulsepump (they aren't really up for the job in the first place), with a small electric low pressure pump (0,3 BAR). This solution has solved a few problems for me, on Briggs and Stratton engines, and Suzuki SV650S. Hopes this helps.
Wrong information which will confuse him. The sloshing is causing the bowls to go empty. Pulse pumps only work when the engines are pulsing so it takes lots of pulls for them to pulse enough fuel back into the bowls. Slushing is a very common issue for those that have fuel cells and do donuts.
the 3rd jet is usually the choke jet. If you follow where the passages in the carb are going you could easily tell what is what. love watching your projects, keep it up👍
One thing that helps with XLT's is called a "boost bottle", it helps with big twins and triples, it basically gives extra plenum volume to the intake system that lessens the bog or laggy throttle response, SLP used to make them, used to make DIY ones too
Chris, remember that without the throttle opening up all the way, you can’t pull in full throttle air flow. The slides need to open up for the engine to run. You’re messing with the main jets with the throttle only opening up on the needle. Fix the throttle and you’ll be amazed!
In the video, when he rides in this small car in a helmet, winds circles, he looks like a small toy car on radio control! Persistent mechanic, Keep up the good work, we love your creations, your videos! "If you suffer for a long time, you will definitely succeed!"
I feel like you struggle to find a lot of things that your googling because your doing a lot of things people are not doing. So much custom work. I'm sure your videos have taught a lot of people things!
The outer ring isn't what you want to focus on. When Reading a plug the "Reading" part is referencing the color of the electrode in the center. A sandy tan like camel color is what you're looking for. This indicates a happy 😊 engine
outer ring is good for checking your idle mixture. Unfortunately, if you're running E10 (over 90% of fuel available these days) reading the electrode is really hard. that little bit of alcohol cleans up the ceramic.
One thing I’ve never really cared about was constant donuts. Most UA-camrs spend every second on film doing donuts to show their rides but maybe I’m getting old lol donuts and wheelies don’t excite me anymore 😂 It’s almost like when you let your friend ride your new quad and he immediately does 27 donuts, gets off and says it’s cool. Dude you didn’t even ride it lol
This is probably one of my favorite builds next to the grave ninja!! Chris, your belt is sitting too high in the secondary clutch, you want the top of the belt to be even with the sheaves with no slip if you pull on it. Also, your clutch, center. And mag side carbs will not be tuned the same! Center and clutch side cyls will be richer than mag side! Sometimes even jetted differently. It isnt revving out like it should and seems a bit lean personally.
What a great video! I’m glad you got it running and that Brian is such a nice guy. Glad he’s kind and respects you and the work you do. Good to go back and forth and tune it!
The engine isn't stupid, and you don't need to find a new one. You only need to find a friend nearby that knows 2 strokes that can help you and teach how it works 😉
he should get a hold of another youtuber named 2vintage he works on motors all the time and is good at tuning them, would be cool to see them Collaborate on a video .
Love this build! Just a thought, have you checked the crank seals? While idling spray something flammable by the seals,if it revs up they need replacing. Good luck! Oh and tune by the color of the electrode,try for a light brown color. Looks like a absolute blast!!!
Good job you are getting there. Glad you did the longer video for this video it was really nice not to have to wait and find out the results of what you did.
• For general use: An AFR between 12:1 and 14:1 is usually optimal for a two-stroke engine, balancing power output and engine temperature. • For specific conditions: You might adjust the AFR depending on whether you prioritize power (richer) or fuel economy (leaner). However, for most two-stroke engines, erring on the side of a richer mixture is often safer due to the cooling needs - by The Way , Cooool build 👌🏻
I have run several snowmobile engines on go karts and never had fuel starvation because the tank was above the carbs. A small electric fuel pump feeding a surge tank above the carbs will eliminate the lean problem. Just have the pump fill the surge tank and run a return line to the main tank so the pump doesn't need to make pressure.
All throughout this project I was thinking, "this is going to look so weird". I was so wrong, it's actually badass, especially seeing it rip around at those speeds. All it really needs is a paintjob.
Im kinda hoping for some fluorescent colors like the 80s sand rails, buggies are one of the few vehicles that can still look cool with the tackiest gaudy liveries possible
Also, do NOT under amy circumstances delete the oil injection system on a 3 cyl polaris engine!! You need it for good crank lubrication and proper ratio of using stock jetting. If you renive the oil injection and run pre mix it will be too lean every time! Keep up the good work brother!!
Buy whole snowmobile. 2006 Skidoo Mach Z 1000 SDi with electronic Reverse. Always see them for sale here in NY. If you want a 600 or 800 get a Skidoo motor with RER standard electric reverse.
Polaris made a fuel injected 650 triple back in the early 90’s it was the Indy 650 rxl. The best way to get one would be in a complete sled it would probably be a bolt in swap in place of that xlt motor. One of those sleds complete would probably be pretty cheap
I'm going to have to agree with a few of the other comments on here, put baffles in the fuel tank. That will greatly reduce the fuel sloshing while taking hard corners and starving the carbs and engine for fuel. Ski Doo/Bombardier/Rotax engines are really excellent. You might have to try doing Craigslist and doing areas like Minneapolis/St Paul, Milwaukee, Eau Claire, Wisconsin, Fargo, North Dakota to find a fuel injected snowmobile. However a lot of people are keeping their sleds with fuel injection for the same reason you are no fan of carburetors, not much tuning and they start up a lot nicer. I've got a fan cooled Suzuki Spirit 500cc from a 1978 Arctic Cat Panther 5000 that I'll be putting into a mini buggy. Using a single Mikuni carb, but since I live in the Midwest, similar to Junkyard Digs but in Nebraska, I'll have to tune it for summer and winter and more aggressively because it's an air/fan cooled 2 stroke. Those really run hot and can't go much above 375⁰F without running the risk of melting down.
Come to MN, I saw a 02 Yamaha 600 efi for $700 today. Runs and rides. I bought it. Also, consider an older Polaris engine, it is still 2 stroke and has a built in cvt
Glad you're getting scientific about the tuning! For a carb, shoot for at least 12:1 at WOT from half RPM up to full RPM (assuming 10% Ethanol). If you've got "good gas", you can run 12.5/13:1. The AEM may need to be periodically calibrated to make sure it's reading right. However, watching the video, the engine seems to run a LOT better down in the 12's...it may be that you need to enrich the mixture even more until you can get fully into the main jet. You might need to put a shim (brass washer) under the needle to raise it up in the seat slightly, and then work on the throttle so you can get a system that will let you get into the main jet fully. If you're changing main jets, but not opening up fully, you're not getting the results you're looking for. If you really want to go nuts, go huge on the jets and fill it with an RC Car fuel with like 20% Nitromethane and you'll be breaking necks in no time! If you're looking for another Wideband for a future project, check out the Innovate Motorsports MTX-L. It's a similar gauge style setup, but a little bit easier to setup. I've run it on everything from Motorcycles to big V8's and it's dead simple.
With belt conditioning you want to do heat cycles. Bring it up to temp, then cool it off over and over several times. Until you do that you don’t want to full send it.
That thing rips in a straight line!! I'm thinking 3 new carbs with deeper float bowls and a baffle in the fuel cell would solve 90% of your issues. Then you can adjust the jetting for the other 10% of tune. Those existing float bowls are very shallow. Hope this is a good suggestion. 👍
Needle and needle jet: When the throttle is opened, the slide lifts the area between the needle and the jet needle, allowing more fuel to be sucked through the main jet to the main air passage. This circuit is responsible for mid throttle.  Main jet: Allows more fuel to be sucked through to the main air passage when the throttle is opened.
14.7:1 is optimal. Lowering the needles in the slides by one groove might get you in there. Changing the main jet should never be more than by 3 points from the original jet size, typically. You can back out the air bleed screw by 1/2 turn to fine tune the idle mixture. Drilling jets... Worse case, you solder them and drill as needed to correct a mistake! Done it on many carbs over the years. Testing, you need to bring up the rpm and hold it rather than rapping and releasing the throttle. On decel, it will go rich, this is normal since vacuum goes to the moon!! I had an XLT that was trouble free for more than 15,000 miles of hard use. They are reliable but need to be dialed in. All you needed to do with the #2 hole is replace that failed coil. Getting the fuel ratio dialed in is a multi step ordeal. There is an idle circuit as well as main circuit that need adjusted accordingly. Set float level correctly!! Too low and cornering will cause it to lay down. There were no plastic baffles surrounding the main jet like moto's have, so me thinks it is the fuel sloshing to one side and float level needs increased and/or baffles installed.
Isn't stoich way too lean for hot rodding a two stroke? I feel like on the pipe he's probably way safer in the 12-13 range. It would really be a bummer to cook this thing by giving it a tune optimized for fuel economy when it's a little dirt monster.
How do you go about soldering jets? I've tried a couple of times and I make it look like a bolt but it works after I make a new slit for flathead......what kinda flux are you using?
@leehuntley189 lots of cleaning and then regular pipe flux for plumbing will work fine. Honestly jets are so cheap and readily available now that there isn't a lot of reason to fill and drill but it is a nice trick to keep in your back pocket for when you get in a pinch.
Btw I think there was a misread on the gauge. The AF ratio is the ratio of air to fuel thus a higher number is lean. In the video the idle was ~18 and this is a lean condition... 12 and lower is a rich condition.
Love this build, love the trophy truck or stadium truck suspension squat, etc...when you are rolling out....soo badass! Especially in that little bug body. Anyhow, also keep in mind if you ever want to go fuel injected, it's fairly simple to steal fuel injection off a dirtbike or street bike and build an airbox for your single throttlebody type setup, etc... lots of videos of people doing it for turbo builds. Sayjng fairly simple as you do fab work. Just an FYI for future builds or if you really decide to fuel inject it. Reach out to guys that put turbo kits on their stuff, most use very similar setups.
Chris try this on those third jets you know nothing about . Ihad the 750 suzuki kettle 3 cylinder water cooled with nearly the same carbs on it. I did a fast port job and jetted up i opened up those third jets i was told by a uk bike shop they are to stop the flushing out of fuel. They add more fuel when booting it and hard corners . Ok. Open them up around the same as the pilots . Hope it helps . Im in the uk 66 year old bike head raced on roads tracks and moto cross . All on 2 strokes too. They all were modified big times . Be patient you will get that triple to sing and scream like its going to hell . Always be safe . Ok . Bye now . Let me know if my tip helped .
Not going to lie, that O2 sensor will be more of a headache for you than a help. Tuning a 2 stroke it should be used as a way to keep an eye on an already known tune, not for tuning itself. Oils and water will kill the sensor and the turbulent air in a 2 stroke exhaust will cause issues, at best you need to take an average of the reading through the RPM ranges to get a decent number. 2 strokes have a short circuit fresh air to the exhaust so saying “it needs to be XX:1 to run right” at all RPM’s is going to be impossible to target and even harder to keep.
Long read but here it is for your knowledge. A correctly jetted carburetor makes a tremendous difference in the torque, mid-range pull, top-end pull, and over-rev of your engine. If you have never jetted your bike correctly, you will almost certainly gain some performance at some point in the bike’s power-band. A cleanly jetted pilot circuit can be the difference between having to clutch the bike out of a turn or not. Hard starting when hot or cold, poor response when opening the throttle, reluctance to idle, all of these are symptoms of an improperly sized pilot jet or incorrectly adjusted air screw. The needle can make all the difference in the world for the power of the machine in most situations, as it controls the throttle range that most riders spend most of their time using. A correctly sized main jet could mean the difference between being able to rev out high enough to not have to shift one more time at the end of the straight, or the power falling flat on top and requiring you to make that extra shift. Are you fouling plugs? Many people will tell you all sorts of band-aid fixes, from running less oil, to running a hotter plug. Both are incorrect fixes for plug fouling. It’s all in the jetting. An engine that is jetted too rich will have combustion temperatures that are too low to burn the fuel and oil effectively, leading to deposits and wet fouling of the plugs. Do you have spooge? There are the rare instances where a mechanical issue, such as a leaking wet-side crank seal, can cause spooge. But, by and large, this isn’t the case. In most instances, spooge is caused by rich jetting. It has nothing to do with how much oil you mix in the gas, or how hard you ride. An engine that is jetted too rich will have combustion temperatures that are too low to burn the fuel and oil effectively, resulting in deposits, plug fouling, and spooge. Spooge is nothing more than unburned fuel and oil entering the exhaust. The only way to know what jetting changes you will need is by trial-and-error. No one can give you jetting specs, because every bike is different, every rider has a different style, and jetting is totally weather dependent. Unless the person telling you what jets to use is riding an identical bike, on the exact same track, at the same time, his recommendations are meaningless. Someone with a good understanding of jetting can get you in the ball park, but you need to do the testing to determine the correct jetting yourself if you want it right. Jetting is fairly simple, and is a useful skill to learn if you ride a two-stroke and want it to perform at it’s best. It’s very important that you start with the pilot circuit, because the pilot circuit affects the entire throttle range. When you are at full throttle, the main jet is the primary fuel metering device, but the pilot is still delivering fuel as well, adding to the total amount of fuel that your engine is receiving. Before you start to re-jet your bike, you need a clean air filter, a fresh plug (actually you need several plugs to do plug-chop tests for the main jet), and fresh fuel. One important detail: Make sure the engine is in good mechanical condition. If your engine has a worn top-end, fix it first. Trying to jet a worn out engine is a waste of time. The same goes for reeds that don’t seal properly, and a silencer that needs re-packing. Worn reeds will mimic rich jetting, and worn rings will mimic lean jetting. Before you start the jet testing, Install a fresh plug. Set the float level to the proper specs, an incorrect float height will affect your jetting all across the throttle range. All jet testing must be done with the engine at full operating temperature. As already stated, start with the pilot circuit. Turn the air screw all the way in, then turn it out 1.5 turns to start. Start the engine, and turn the idle screw in until you get a slightly fast idle, or hold the throttle just barely cracked, to keep the engine idling. Turn the air screw slowly in, and then out, until you find the point where the idle is fastest. Stop there. Do not open the screw any farther, or your throttle response will be flat and mushy, and the bike may even bog. This is only the starting point, we will still have to tune the air screw for the best response. Is It Rich or Lean? Now is the time to determine if you have the correct pilot installed in your carb. The air screw position determines this for you, making it very simple. If your air screw is less than 1 turn from closed, you need a larger pilot jet. If it is more than 2.5 turns from closed, you need a smaller pilot jet. If your engine doesn’t respond to air screw changes, then you either have a dirty carb, or the pilot jet is way too rich. When the pilot jet is way too rich, you are forced to use the idle screw to open the slide so far in order to keep the engine running that the pilot circuit is partially bypassed, and the engine is actually starting to draw fuel through the needle jet. Once you have determined (and installed it if it’s necessary to change it) the correct pilot jet size, and tuned the air screw for the fastest idle, it’s time to tune the air screw for the best throttle response. Again, make sure the bike is at full operating temperature. Set the idle back down (the bike should still idle, despite what you read in the Moto Tabloids), and ride the bike, using closed-to-1/4 throttle transitions. Turn the air screw slightly in either direction until you find the point that gives you the best response when cracking the throttle open. Most bikes are sensitive to changes as small as 1/8 of a turn. The air screw is not a set-it-and-leave-it adjustment. You have to constantly re-adjust the air screw to compensate for changing outdoor temps and humidity. An air screw setting that is perfect in the cool morning air will likely be too rich in the heat of the mid-day. Now, it’s time to work on the needle. Mark the throttle grip at 1/4 and 3/4 openings. Ride the bike between these two marks. If the bike bogs for a second before responding to throttle, lower the clip (raising the needle) a notch at a time until the engine picks up smoothly. If the bike sputters or sounds rough when giving it throttle, raise the clip (lowering the needle) until it runs cleanly. There isn’t really any way to test the needle other than by feel, but it’s usually quite obvious when it’s right or wrong. A too-rich needle can often be felt simply when revving the bike on the stand. The bike will sound rough and raspy when blipping the throttle on the stand. A correctly jetted bike should rev cleanly and crisply. Last is the main jet. The main jet affects from 1/2 to full throttle. The easiest way to test it is to do a throttle-chop test. With the bike fully warmed up, find a long straight, and install a fresh plug. Start the engine, and do a full-throttle run down the straight, through all gears. As soon as the bike tops out, pull the clutch in, and kill the engine, coasting to a stop. Remove the plug, and look deep down inside the threads, at the base of the insulator. If it is white or gray, the main is too lean. If it is dark brown or black, the main is too rich. The correct color is a medium-dark mocha brown or tan. Please note that, when reading plugs, the tip of the insulator, threads, etc. are meaningless for jetting purposes. They can tell you a lot of things, but jetting isn’t one of them. Only the mixture ring at the very base of the insulator, inside the threads, can tell you anything about the jetting. The slide is also a tuning variable for jetting, affecting the throttle range from 1/8 throttle to approximately 1/3 throttle. If you can’t clean up the small-throttle jetting on your bike no matter how lean you go with the pilot or the needle, the slide is the next step. But few bikes need leaner slides. Keep in mind, even though this article is intended primarily for two-strokes, four-strokes also need proper jetting to perform right, although they are not quite as fussy as their oil-burning cousins. The only real difference in the two is with the pilot circuit. Two-strokes have an air screw that you screw in to make the jetting richer, and screw out to make the jetting leaner. Four-strokes, on the other hand, have a fuel adjustment screw that you screw in to make the jetting leaner, and out to make it richer. Their purpose is the same, they just do it in different ways.
Reach out to ! This is what they do. I'm watching for the simple fact that I want you both to do a co-lab video. That would be cool AF with all their mini projects!
Banshee guy here.. Chris you have to chop a spark plug to read it properly. You also want to warm it up on old plugs, then put new plugs in, run it wide open 0 to top speed, immediately kill the engine, take out the wot we just ran new plugs. Put olds in to drive back. Then chop and read the new plugs with the wot run on them.
Love your creativity on your builds... try adding a anti slosh baffle in your fuel tank that holds more fuel around the pickup for the pump and dump the return into new sump ... this might help... keep up not giving up on this build...😊
Hey dude. So from what I can understand. That third jet is tied in with the enrichment circuit. This gets activated when the choke is applied or, on newer engines because of how finely tuned they are, activates when the carb demands more fuel than your pilot and main jet can supply
When the air filter goes on mixture gets richer. Being a two stroke intake and exhaust pulse plays a big part in performance and tuning Don’t let that piece of metal out smart you. Keep working on it.
🎉its getting there.try mounting a a test gas tank to back of roll bar so it gravity feeds and see if it don't bog when cornering.could be getting air in line from the gas sloshing in the tank you made.
It was a snowmobile engine designed for colder air like 30 degrees now it’s being used in 80 degrees. Colder air/ more fuel. Warmer air/ less fuel. As that motor heats up it will lean itself out. Be careful with the engine temperature. Radiator location is bad. Needs to be up or open to more air flow. You are setting in front of it blocking air. Consider getting more air to it somehow. As for the air filter sometimes they hurt response and change pulse. Try putting a plenum or box on the carbs and mount one bigger air cleaner onto the plenum. Just some thoughts I had. Enjoyed the video. That thing is bad ass.
It was jetted for fuel without oil. Now that you are premixing, you have oil in the fuel also going through the jet. Therefore a bigger jet is needed. Oil mixing needs to be consistent for jetting to be consistent
Every time I watch your videos you remind me of an actor whose name I cannot remember to save my life! It’s your look and mostly your voice! If anyone knows who I am thinking of please tell me!
Kick ass sea bass! That thing is ripping much better, but a couple more small tweaks and it will be flying…. That snowmobile engine has got some power and sounded good at the end.
I'm at the middle point in the video. I keep thinking your fuel is moving to one side of the tank, cutting your fuel off when you turn hard. But not being there makes judging tough. I feel for you, bro. Good luck. Love your vids
Don't be frustrated. It is learning curve. Please do not give up on this engine. As watchers it is highly valuable to do problem solving on this engine and get it near to perfect. Don't go for the easy solution to buy an fuel injected engine. That is not interesting (as a subscriber :-) ) Removing the pod filters really makes it lean. I guess that the afr is not that accurate. I would suggest to go up in main jets. Better to be at 11-12 in afr than 14+. Lean is dangerous. Maybe the burning of the 2 stroke oil is messing with the afr readings My guess about the 3rd jet that it is from the choke circuit. It looks like a keihin style jet so maybe they have been replaced.
I would try a small fuel pump and maybe an air box with one filter on the end. That's how it is on a motorbike, which could help control the air and give a set amount of air in when it first opens up. if that makes sense, I love this build keep it coming 😁🇬🇧
I have an old 1996 440 2 stroke 2 cyl snowmobile engine on an Artic cat that supposedly makes 60hp. You've inspired me to go forward on a golf cart engine swap project. Unfortunately im at the stage of -rather be learning to weld 😆
Engine sounds much better. Pesky plug wires. I don’t know how long the engine will last with the air intake situation. I’d look into some sort of snorkel so it’s not sucking dust.
I've had the same issue with my cross cart that has a snowmobile engine & after much testing & driving myself almost "Batshit Crazy" I built a baffled fuel cell to keep the fuel from being rushed all over the tank because of the torque "G forces" & i also put an inline fuel pump equipped with a pressure regulator & mine will pull in corners as well as straight line !! The jetting was not a real big issue other than the the power through the lower to top end power band !! Hope it helps you & you can get it ripping!! Also after you get the throttle 100% as opposed to the 3/4 like you showed that you had during your testing !!
to get a more accurate reeding of afr i would put the sensor after the expantion chamber. Remember that afr is just a refrence number, not the bible. When i tune carb 2 strokes i'll tune after sound and feel, and then look at plugs to have it live at wot. To be completly shure the engine is happy, you need to learn to read the plugs. AS the brother dude is saying, fix the throttle cable first, then get it to run good in wot with the mains, and then dial in the 3/4 and 1/2 with needle and so on. Love this build to, and good luck tuning this thing. Old 2 stroke triples are known for beeing finneky to dial in, but so satisfying when they run good. And yes, that engine is made for running it on the side, upside down and straight up in a snowmobile with no problem, so drifting should not be an issue. Greetings front the land of snowmobiling North of Norway
A lot of you guys have been asking for longer videos recently, this one is definitely longer than usual. I hope you guys like it.
Love te long video man keep it up you are a the best !!!!
Thanks for the awesome video drop, man!
Hell yes Chris, always here for it.
Just suggestion maybe. Turbo or supercharged it? And give it all the fuel? Idk
I'm sure it's a good idea. but I have about an average attention span of about an hour.
when it comes to electronic fuel injection it is more reliable. but if an issue happens with the ECU (the main computer) for all the engine management. out on the trails there is virtually no fix that can be done. because the micro circuit transistorized components in the ECU. there no fix only replacement but ECU failure is extremely rare.
I was always tought that when reading spark plugs. the ideal color for the plugs should be a chocolate brown color.
and you have to remember that snowmobiles are normally operated in colder ambient temperatures. and that would explain the lean idling condition. because lean engines always run hotter. and rich engines always run cooler. so in the hotter ambient temperatures you would want the engine to run richer.
Yep. Keep it. Learn to dial it in. It is good knowledge to have.
Props to Brian for the troubleshooting and back and forth.
That thing is a sick little ripper!
How cool is Brian! What a great dude.
My Sunday is complete when a new RBW video is posted!
W
3rd jet is a power jet, it pulls extra fuel under load, always love watching your videos especially the longer ones
Power jet or Starter Jet?
@@craigmartin822pretty sure that third jet is a starter jet for when the choke is on
@@dawsongiardino2802 correct enrichner jet for choke
Start jet is right
@@dawsongiardino2802 I agree it's the starter jet
160 is overheat on a sled in winter you need to leave the fan on. My sled runs at 100 in the snow all day long. You need a baffles in the gas tank that's why you are running out of gas on hard corners imo. Great show tho man 👍.We lay sles on there sides and do powder turns all day on sleds with carbs and they dont bog down
Agree, need baffles in the gas tank.
The O2 sensor is on a bad spot. Try moving it a bit further into the narrower part or even the small pipe piece after the expansion chamber. Where it stands now it will only read a fraction of the gases. That´s why u´re getting a false reading. It doesn´t matter if it´s a 2 or a 4 stroke, the O2 sensor has to be mounted where it can read the most ammount of exaust gases possible. Hope this helps u get a better tunning. Doesn´t matter if it´s a bike, a snowmobile or a car. The principle is the same regarding O2 sensors. About the third jet, it´s a power jet. It´s main objective is to compensate for the lack of fuel at higher RPM. With those carbs u can finetune idle, mid range and high RPM seperately to get the most power out of the full range of the engine. Love your vids. Have fun and keep hustling. 🦾
I have been watching you struggle with small engine repairs for years. Its time you cracked a book and learn about engines. You can do it!
ChatGPT will do it
From some random dude with no videos giving mechanics advice....😂😂😂
@@michi_danksta and no suggestions as to what books to start with.
Great great video! I’ve been watching this project from the very beginning and it looks so cool.
Hey Chris 🙂 When its starved after the donuts, and you almost can't start it again, it tells me that the floats are empty, and its not a "slushing" problem.
I would look to replace the pulsepump (they aren't really up for the job in the first place), with a small electric low pressure pump (0,3 BAR).
This solution has solved a few problems for me, on Briggs and Stratton engines, and Suzuki SV650S. Hopes this helps.
That is what I thought maybe some variable pressure pump
The factory pulse pump kept up with snowcross racing just fine.
@@isaacclark6749agreed, oval racing, snow cross, cross country. I've never had one "not be up to the task"
I’d agree the pulse pump
Wrong information which will confuse him. The sloshing is causing the bowls to go empty. Pulse pumps only work when the engines are pulsing so it takes lots of pulls for them to pulse enough fuel back into the bowls. Slushing is a very common issue for those that have fuel cells and do donuts.
the 3rd jet is usually the choke jet. If you follow where the passages in the carb are going you could easily tell what is what.
love watching your projects, keep it up👍
Black carbon build up on plugs = rich , white/grey buildup = lean , chocolate brown = perfect
One thing that helps with XLT's is called a "boost bottle", it helps with big twins and triples, it basically gives extra plenum volume to the intake system that lessens the bog or laggy throttle response, SLP used to make them, used to make DIY ones too
Chris, remember that without the throttle opening up all the way, you can’t pull in full throttle air flow. The slides need to open up for the engine to run. You’re messing with the main jets with the throttle only opening up on the needle. Fix the throttle and you’ll be amazed!
Definitely and would you say the carbs need balancing coz they always seem to need tweeting every time you take them off ?
@@gazgazistwhen you take off multiple carbs you always have to resync them. According to Super Bike Surgery
There's something wrong with the fuel
You may have the same problem with a fuel injected engine it's either not getting fuel something's going on
Air filters make a big difference on a 2-stroke you need to design something
In the video, when he rides in this small car in a helmet, winds circles, he looks like a small toy car on radio control!
Persistent mechanic, Keep up the good work, we love your creations, your videos!
"If you suffer for a long time, you will definitely succeed!"
Seeing Brad standing next to your buggy tells us how really small it is. We all knew it was small , and you knew it was small but wow!
I feel like you struggle to find a lot of things that your googling because your doing a lot of things people are not doing. So much custom work. I'm sure your videos have taught a lot of people things!
Your friend is a good dude..patient and knowledgable👍
The outer ring isn't what you want to focus on. When Reading a plug the "Reading" part is referencing the color of the electrode in the center. A sandy tan like camel color is what you're looking for. This indicates a happy 😊 engine
outer ring is good for checking your idle mixture. Unfortunately, if you're running E10 (over 90% of fuel available these days) reading the electrode is really hard. that little bit of alcohol cleans up the ceramic.
Do you mean the porcelain insulation around the electrode?🤔
Read the ceramic cone in the middle
The mixture adjustment screw on the carbs controls idle enrichment, mostly. It control air or fuel depending on brand, so adjust and check
Don't get frustrated if you do step back relax then get back into it that engine is coming around ❤❤❤❤❤
One thing I’ve never really cared about was constant donuts. Most UA-camrs spend every second on film doing donuts to show their rides but maybe I’m getting old lol donuts and wheelies don’t excite me anymore 😂
It’s almost like when you let your friend ride your new quad and he immediately does 27 donuts, gets off and says it’s cool. Dude you didn’t even ride it lol
Donuts and burnouts are a total waste and abusive
Get a temperature switch that will turn on the fan automatically at a set temperature.
CHRIS, AN HOUR AND A HALF!?? I can't wait to watch the whole thing!
Toughen up buttercup
I had go schedule it in with my wife to watch this !!!!!!!!! Then I realized im happily single!!!!! Yay & lol
This is probably one of my favorite builds next to the grave ninja!! Chris, your belt is sitting too high in the secondary clutch, you want the top of the belt to be even with the sheaves with no slip if you pull on it. Also, your clutch, center. And mag side carbs will not be tuned the same! Center and clutch side cyls will be richer than mag side! Sometimes even jetted differently. It isnt revving out like it should and seems a bit lean personally.
Bro just gave us two weeks of videos in one. Salute RBW!
What a great video! I’m glad you got it running and that Brian is such a nice guy. Glad he’s kind and respects you and the work you do. Good to go back and forth and tune it!
The engine isn't stupid, and you don't need to find a new one. You only need to find a friend nearby that knows 2 strokes that can help you and teach how it works 😉
True but they live in the south I bet that kinda friend is hard to find, that knows 2stroke snowmobile engines.
That's the right answer to that problem !!! You have to know what you're talking about when it's about jetting 2 strokes. Greetings from France...
he should get a hold of another youtuber named 2vintage he works on motors all the time and is good at tuning them, would be cool to see them Collaborate on a video .
100%
Take it to a jetski mechanic 👌
Also wanted to give you kudos for switching to the round headlights they look so much better 👌
Love this build! Just a thought, have you checked the crank seals? While idling spray something flammable by the seals,if it revs up they need replacing. Good luck! Oh and tune by the color of the electrode,try for a light brown color.
Looks like a absolute blast!!!
Good job you are getting there. Glad you did the longer video for this video it was really nice not to have to wait and find out the results of what you did.
Chris is a humble guy. Always admitting when he was wrong and happy to learn from others.
• For general use: An AFR between 12:1 and 14:1 is usually optimal for a two-stroke engine, balancing power output and engine temperature.
• For specific conditions: You might adjust the AFR depending on whether you prioritize power (richer) or fuel economy (leaner). However, for most two-stroke engines, erring on the side of a richer mixture is often safer due to the cooling needs
- by The Way , Cooool build 👌🏻
I have run several snowmobile engines on go karts and never had fuel starvation because the tank was above the carbs. A small electric fuel pump feeding a surge tank above the carbs will eliminate the lean problem. Just have the pump fill the surge tank and run a return line to the main tank so the pump doesn't need to make pressure.
Fuel pump to a surge tank would most certainly take care of the issue as long as the surge tank is above the carbs.
Wow that thing really rips! Sure looks like it's running good enough! 👍👍
All throughout this project I was thinking, "this is going to look so weird". I was so wrong, it's actually badass, especially seeing it rip around at those speeds. All it really needs is a paintjob.
Kinda hoping he paints it white with a red & blue racing stripe.
Paint it like Herbie.
@gregwebb8939 yes! Herbie style!
Im kinda hoping for some fluorescent colors like the 80s sand rails, buggies are one of the few vehicles that can still look cool with the tackiest gaudy liveries possible
Herbi
Takeit easy bro that thing rips. Your a great machinist and fabricator .
im here just to say how sick this thing looks
I think the long travel makes this buggy badass
Also, do NOT under amy circumstances delete the oil injection system on a 3 cyl polaris engine!! You need it for good crank lubrication and proper ratio of using stock jetting. If you renive the oil injection and run pre mix it will be too lean every time! Keep up the good work brother!!
But isn't it getting the same mixture with premix. It's mixing in the carb anyway isn't it?
@@centennialfarm11No it's not they oil goes to multiple bearings going to premix will kill the motor
@@centennialfarm11there's an oil line that feeds one of the crank bearings
You are 100% correct Polaris is one of the only company’s you don’t want to delete there oil injection systems on same with there pwcs.
It's done all the time with no problems.
Love the bug. One of your best builds. You need some curved vent "windows" to blow more air in the rad. Like the side back windows in a Bug.
Buy whole snowmobile. 2006 Skidoo Mach Z 1000 SDi with electronic Reverse. Always see them for sale here in NY. If you want a 600 or 800 get a Skidoo motor with RER standard electric reverse.
You're insane! 🤣 Soooo glad you are getting the right help. You're learning and I'm learning. Awesome!
Brother! I have a suggestion. Tape off a section of the intake. Tape it off until it runs best and that will help you gauge how lean it needs to be.
Polaris made a fuel injected 650 triple back in the early 90’s it was the Indy 650 rxl. The best way to get one would be in a complete sled it would probably be a bolt in swap in place of that xlt motor. One of those sleds complete would probably be pretty cheap
Also, those shocks look way more dialed in than last time. Nice!
I'm going to have to agree with a few of the other comments on here, put baffles in the fuel tank. That will greatly reduce the fuel sloshing while taking hard corners and starving the carbs and engine for fuel.
Ski Doo/Bombardier/Rotax engines are really excellent. You might have to try doing Craigslist and doing areas like Minneapolis/St Paul, Milwaukee, Eau Claire, Wisconsin, Fargo, North Dakota to find a fuel injected snowmobile. However a lot of people are keeping their sleds with fuel injection for the same reason you are no fan of carburetors, not much tuning and they start up a lot nicer.
I've got a fan cooled Suzuki Spirit 500cc from a 1978 Arctic Cat Panther 5000 that I'll be putting into a mini buggy. Using a single Mikuni carb, but since I live in the Midwest, similar to Junkyard Digs but in Nebraska, I'll have to tune it for summer and winter and more aggressively because it's an air/fan cooled 2 stroke. Those really run hot and can't go much above 375⁰F without running the risk of melting down.
You were right the first time about the numbers I think. Higher is richer. Rich bogs you down, lean surges and hunts for a rpm to run at.
WHOA... A whole sunday full length movie... Not bad... not bad at all...
You guy's Rock & i SOOOOOO look forward to your next videos & when you guys get the cart ripping full tilt it's going to be Freaking Insane !!
Come to MN, I saw a 02 Yamaha 600 efi for $700 today. Runs and rides. I bought it. Also, consider an older Polaris engine, it is still 2 stroke and has a built in cvt
Glad you're getting scientific about the tuning! For a carb, shoot for at least 12:1 at WOT from half RPM up to full RPM (assuming 10% Ethanol). If you've got "good gas", you can run 12.5/13:1. The AEM may need to be periodically calibrated to make sure it's reading right.
However, watching the video, the engine seems to run a LOT better down in the 12's...it may be that you need to enrich the mixture even more until you can get fully into the main jet. You might need to put a shim (brass washer) under the needle to raise it up in the seat slightly, and then work on the throttle so you can get a system that will let you get into the main jet fully. If you're changing main jets, but not opening up fully, you're not getting the results you're looking for.
If you really want to go nuts, go huge on the jets and fill it with an RC Car fuel with like 20% Nitromethane and you'll be breaking necks in no time!
If you're looking for another Wideband for a future project, check out the Innovate Motorsports MTX-L. It's a similar gauge style setup, but a little bit easier to setup. I've run it on everything from Motorcycles to big V8's and it's dead simple.
With belt conditioning you want to do heat cycles. Bring it up to temp, then cool it off over and over several times. Until you do that you don’t want to full send it.
That thing rips in a straight line!! I'm thinking 3 new carbs with deeper float bowls and a baffle in the fuel cell would solve 90% of your issues. Then you can adjust the jetting for the other 10% of tune. Those existing float bowls are very shallow. Hope this is a good suggestion. 👍
After you get the carbs working at full throttle, you could / should also synchronize the carbs probably.
Triples induce giggling! But if you're dead set on fuel injection, cram a skidoo 800 Etec in there. But use the correct expansion chamber.
Needle and needle jet: When the throttle is opened, the slide lifts the area between the needle and the jet needle, allowing more fuel to be sucked through the main jet to the main air passage. This circuit is responsible for mid throttle.

Main jet: Allows more fuel to be sucked through to the main air passage when the throttle is opened.
Love the longer videos! So much talent!
14.7:1 is optimal. Lowering the needles in the slides by one groove might get you in there. Changing the main jet should never be more than by 3 points from the original jet size, typically. You can back out the air bleed screw by 1/2 turn to fine tune the idle mixture. Drilling jets... Worse case, you solder them and drill as needed to correct a mistake! Done it on many carbs over the years.
Testing, you need to bring up the rpm and hold it rather than rapping and releasing the throttle. On decel, it will go rich, this is normal since vacuum goes to the moon!!
I had an XLT that was trouble free for more than 15,000 miles of hard use. They are reliable but need to be dialed in. All you needed to do with the #2 hole is replace that failed coil. Getting the fuel ratio dialed in is a multi step ordeal. There is an idle circuit as well as main circuit that need adjusted accordingly. Set float level correctly!! Too low and cornering will cause it to lay down. There were no plastic baffles surrounding the main jet like moto's have, so me thinks it is the fuel sloshing to one side and float level needs increased and/or baffles installed.
Isn't stoich way too lean for hot rodding a two stroke? I feel like on the pipe he's probably way safer in the 12-13 range. It would really be a bummer to cook this thing by giving it a tune optimized for fuel economy when it's a little dirt monster.
12.6 is the best for WOT performance.
How do you go about soldering jets? I've tried a couple of times and I make it look like a bolt but it works after I make a new slit for flathead......what kinda flux are you using?
@leehuntley189 lots of cleaning and then regular pipe flux for plumbing will work fine. Honestly jets are so cheap and readily available now that there isn't a lot of reason to fill and drill but it is a nice trick to keep in your back pocket for when you get in a pinch.
14.7 is the cleanest burning not the best running. Max power is usually around the 12 to 13 range
This thing, when running right, will be a quality contender to GHPC's Colonel Senders!
Btw I think there was a misread on the gauge. The AF ratio is the ratio of air to fuel thus a higher number is lean. In the video the idle was ~18 and this is a lean condition... 12 and lower is a rich condition.
Love this build, love the trophy truck or stadium truck suspension squat, etc...when you are rolling out....soo badass! Especially in that little bug body. Anyhow, also keep in mind if you ever want to go fuel injected, it's fairly simple to steal fuel injection off a dirtbike or street bike and build an airbox for your single throttlebody type setup, etc... lots of videos of people doing it for turbo builds. Sayjng fairly simple as you do fab work. Just an FYI for future builds or if you really decide to fuel inject it. Reach out to guys that put turbo kits on their stuff, most use very similar setups.
Chris try this on those third jets you know nothing about . Ihad the 750 suzuki kettle 3 cylinder water cooled with nearly the same carbs on it. I did a fast port job and jetted up i opened up those third jets i was told by a uk bike shop they are to stop the flushing out of fuel. They add more fuel when booting it and hard corners . Ok. Open them up around the same as the pilots . Hope it helps . Im in the uk 66 year old bike head raced on roads tracks and moto cross . All on 2 strokes too. They all were modified big times . Be patient you will get that triple to sing and scream like its going to hell . Always be safe . Ok . Bye now . Let me know if my tip helped .
this is the best little car build on yt
Not going to lie, that O2 sensor will be more of a headache for you than a help. Tuning a 2 stroke it should be used as a way to keep an eye on an already known tune, not for tuning itself. Oils and water will kill the sensor and the turbulent air in a 2 stroke exhaust will cause issues, at best you need to take an average of the reading through the RPM ranges to get a decent number. 2 strokes have a short circuit fresh air to the exhaust so saying “it needs to be XX:1 to run right” at all RPM’s is going to be impossible to target and even harder to keep.
Long read but here it is for your knowledge.
A correctly jetted carburetor makes a tremendous difference in the torque, mid-range pull, top-end pull, and over-rev of your engine. If you have never jetted your bike correctly, you will almost certainly gain some performance at some point in the bike’s power-band.
A cleanly jetted pilot circuit can be the difference between having to clutch the bike out of a turn or not. Hard starting when hot or cold, poor response when opening the throttle, reluctance to idle, all of these are symptoms of an improperly sized pilot jet or incorrectly adjusted air screw.
The needle can make all the difference in the world for the power of the machine in most situations, as it controls the throttle range that most riders spend most of their time using.
A correctly sized main jet could mean the difference between being able to rev out high enough to not have to shift one more time at the end of the straight, or the power falling flat on top and requiring you to make that extra shift.
Are you fouling plugs? Many people will tell you all sorts of band-aid fixes, from running less oil, to running a hotter plug. Both are incorrect fixes for plug fouling. It’s all in the jetting. An engine that is jetted too rich will have combustion temperatures that are too low to burn the fuel and oil effectively, leading to deposits and wet fouling of the plugs.
Do you have spooge? There are the rare instances where a mechanical issue, such as a leaking wet-side crank seal, can cause spooge. But, by and large, this isn’t the case. In most instances, spooge is caused by rich jetting. It has nothing to do with how much oil you mix in the gas, or how hard you ride. An engine that is jetted too rich will have combustion temperatures that are too low to burn the fuel and oil effectively, resulting in deposits, plug fouling, and spooge. Spooge is nothing more than unburned fuel and oil entering the exhaust.
The only way to know what jetting changes you will need is by trial-and-error. No one can give you jetting specs, because every bike is different, every rider has a different style, and jetting is totally weather dependent. Unless the person telling you what jets to use is riding an identical bike, on the exact same track, at the same time, his recommendations are meaningless. Someone with a good understanding of jetting can get you in the ball park, but you need to do the testing to determine the correct jetting yourself if you want it right.
Jetting is fairly simple, and is a useful skill to learn if you ride a two-stroke and want it to perform at it’s best.
It’s very important that you start with the pilot circuit, because the pilot circuit affects the entire throttle range. When you are at full throttle, the main jet is the primary fuel metering device, but the pilot is still delivering fuel as well, adding to the total amount of fuel that your engine is receiving.
Before you start to re-jet your bike, you need a clean air filter, a fresh plug (actually you need several plugs to do plug-chop tests for the main jet), and fresh fuel.
One important detail: Make sure the engine is in good mechanical condition. If your engine has a worn top-end, fix it first. Trying to jet a worn out engine is a waste of time. The same goes for reeds that don’t seal properly, and a silencer that needs re-packing. Worn reeds will mimic rich jetting, and worn rings will mimic lean jetting.
Before you start the jet testing, Install a fresh plug. Set the float level to the proper specs, an incorrect float height will affect your jetting all across the throttle range.
All jet testing must be done with the engine at full operating temperature.
As already stated, start with the pilot circuit. Turn the air screw all the way in, then turn it out 1.5 turns to start. Start the engine, and turn the idle screw in until you get a slightly fast idle, or hold the throttle just barely cracked, to keep the engine idling. Turn the air screw slowly in, and then out, until you find the point where the idle is fastest. Stop there. Do not open the screw any farther, or your throttle response will be flat and mushy, and the bike may even bog. This is only the starting point, we will still have to tune the air screw for the best response.
Is It Rich or Lean?
Now is the time to determine if you have the correct pilot installed in your carb. The air screw position determines this for you, making it very simple. If your air screw is less than 1 turn from closed, you need a larger pilot jet. If it is more than 2.5 turns from closed, you need a smaller pilot jet. If your engine doesn’t respond to air screw changes, then you either have a dirty carb, or the pilot jet is way too rich. When the pilot jet is way too rich, you are forced to use the idle screw to open the slide so far in order to keep the engine running that the pilot circuit is partially bypassed, and the engine is actually starting to draw fuel through the needle jet.
Once you have determined (and installed it if it’s necessary to change it) the correct pilot jet size, and tuned the air screw for the fastest idle, it’s time to tune the air screw for the best throttle response. Again, make sure the bike is at full operating temperature. Set the idle back down (the bike should still idle, despite what you read in the Moto Tabloids), and ride the bike, using closed-to-1/4 throttle transitions. Turn the air screw slightly in either direction until you find the point that gives you the best response when cracking the throttle open. Most bikes are sensitive to changes as small as 1/8 of a turn.
The air screw is not a set-it-and-leave-it adjustment. You have to constantly re-adjust the air screw to compensate for changing outdoor temps and humidity. An air screw setting that is perfect in the cool morning air will likely be too rich in the heat of the mid-day.
Now, it’s time to work on the needle. Mark the throttle grip at 1/4 and 3/4 openings. Ride the bike between these two marks. If the bike bogs for a second before responding to throttle, lower the clip (raising the needle) a notch at a time until the engine picks up smoothly. If the bike sputters or sounds rough when giving it throttle, raise the clip (lowering the needle) until it runs cleanly. There isn’t really any way to test the needle other than by feel, but it’s usually quite obvious when it’s right or wrong. A too-rich needle can often be felt simply when revving the bike on the stand. The bike will sound rough and raspy when blipping the throttle on the stand. A correctly jetted bike should rev cleanly and crisply.
Last is the main jet. The main jet affects from 1/2 to full throttle. The easiest way to test it is to do a throttle-chop test. With the bike fully warmed up, find a long straight, and install a fresh plug. Start the engine, and do a full-throttle run down the straight, through all gears. As soon as the bike tops out, pull the clutch in, and kill the engine, coasting to a stop. Remove the plug, and look deep down inside the threads, at the base of the insulator. If it is white or gray, the main is too lean. If it is dark brown or black, the main is too rich. The correct color is a medium-dark mocha brown or tan.
Please note that, when reading plugs, the tip of the insulator, threads, etc. are meaningless for jetting purposes. They can tell you a lot of things, but jetting isn’t one of them. Only the mixture ring at the very base of the insulator, inside the threads, can tell you anything about the jetting.
The slide is also a tuning variable for jetting, affecting the throttle range from 1/8 throttle to approximately 1/3 throttle. If you can’t clean up the small-throttle jetting on your bike no matter how lean you go with the pilot or the needle, the slide is the next step. But few bikes need leaner slides.
Keep in mind, even though this article is intended primarily for two-strokes, four-strokes also need proper jetting to perform right, although they are not quite as fussy as their oil-burning cousins. The only real difference in the two is with the pilot circuit.
Two-strokes have an air screw that you screw in to make the jetting richer, and screw out to make the jetting leaner. Four-strokes, on the other hand, have a fuel adjustment screw that you screw in to make the jetting leaner, and out to make it richer. Their purpose is the same, they just do it in different ways.
Reach out to ! This is what they do. I'm watching for the simple fact that I want you both to do a co-lab video. That would be cool AF with all their mini projects!
You need to balance the carbs. The o2 will only give an average.
If you pull the plugs after you might be able to tell the difference between the carbs
Banshee guy here.. Chris you have to chop a spark plug to read it properly. You also want to warm it up on old plugs, then put new plugs in, run it wide open 0 to top speed, immediately kill the engine, take out the wot we just ran new plugs. Put olds in to drive back. Then chop and read the new plugs with the wot run on them.
This might sound weird, but that thing wants to be robin egg blue!
Maybe with an orange frame.
@@tinkerne-round4079 sounds kinda GULF to me that does
If you go with a motorcycle engine. You can try and get a rekluse clutch which allows it to run like an automatic.
You could look at bigger scooter engines, they are all CVT and go up to several hundred CCs. Also commonly fuel injected!
And the newer ones are 4-strokes and have EFI.
Love your creativity on your builds... try adding a anti slosh baffle in your fuel tank that holds more fuel around the pickup for the pump and dump the return into new sump ... this might help... keep up not giving up on this build...😊
You need baffles in your gas tank to help keep the gas deeper around the fule outlet
I thought he did put in baffles when he built the tank, and if it was starving for fuel wouldn't it show on the 02?
@@centennialfarm11maybe I missed it, it has an O2 sensor? Usually carbureted snowmobiles if anything only have a egt sensor
@@isaacclark6749 you didnt watch the video did you?
@@ghostpig8012 lol no, still watching it. That's what I get for commenting before I finish it.
Cool thing!!! It looks like a head driving it, with your sticking out!!!!!Stiffen that rear end up, it'll wheelie, like a champ!!!
Hey dude. So from what I can understand. That third jet is tied in with the enrichment circuit. This gets activated when the choke is applied or, on newer engines because of how finely tuned they are, activates when the carb demands more fuel than your pilot and main jet can supply
Or in some Carbs, there is an extra air channel, only used in full throttle, where the third jet is goun to
When the air filter goes on mixture gets richer. Being a two stroke intake and exhaust pulse plays a big part in performance and tuning Don’t let that piece of metal out smart you. Keep working on it.
"fuel injection just works!" I couldn't agree more.
🎉its getting there.try mounting a a test gas tank to back of roll bar so it gravity feeds and see if it don't bog when cornering.could be getting air in line from the gas sloshing in the tank you made.
It was a snowmobile engine designed for colder air like 30 degrees now it’s being used in 80 degrees. Colder air/ more fuel. Warmer air/ less fuel. As that motor heats up it will lean itself out. Be careful with the engine temperature. Radiator location is bad. Needs to be up or open to more air flow. You are setting in front of it blocking air. Consider getting more air to it somehow. As for the air filter sometimes they hurt response and change pulse. Try putting a plenum or box on the carbs and mount one bigger air cleaner onto the plenum. Just some thoughts I had. Enjoyed the video. That thing is bad ass.
It was jetted for fuel without oil. Now that you are premixing, you have oil in the fuel also going through the jet. Therefore a bigger jet is needed. Oil mixing needs to be consistent for jetting to be consistent
Every time I watch your videos you remind me of an actor whose name I cannot remember to save my life! It’s your look and mostly your voice! If anyone knows who I am thinking of please tell me!
Young Tom Hanks maybe
Fuel is getting richer and it's also not smoking as much
Kick ass sea bass! That thing is ripping much better, but a couple more small tweaks and it will be flying…. That snowmobile engine has got some power and sounded good at the end.
Pretty sure the other jet should be a mid range jet check your float level could definitely cause the issue while cornering. love the vids keep it up
I'm at the middle point in the video. I keep thinking your fuel is moving to one side of the tank, cutting your fuel off when you turn hard. But not being there makes judging tough. I feel for you, bro. Good luck. Love your vids
I knew this was going to be awesome! Great job!!!
Looks like so much fun Chris. If you want it to pick up the inside front wheel more, put a swaybar in the front but not the back.
Don't be frustrated. It is learning curve. Please do not give up on this engine. As watchers it is highly valuable to do problem solving on this engine and get it near to perfect. Don't go for the easy solution to buy an fuel injected engine. That is not interesting (as a subscriber :-) )
Removing the pod filters really makes it lean. I guess that the afr is not that accurate. I would suggest to go up in main jets. Better to be at 11-12 in afr than 14+. Lean is dangerous. Maybe the burning of the 2 stroke oil is messing with the afr readings
My guess about the 3rd jet that it is from the choke circuit. It looks like a keihin style jet so maybe they have been replaced.
I would try a small fuel pump and maybe an air box with one filter on the end. That's how it is on a motorbike, which could help control the air and give a set amount of air in when it first opens up. if that makes sense, I love this build keep it coming 😁🇬🇧
Very cool project. Sure would like to see you have some effective rollover protection. Stay safe!
Im gonna say this is probably the sickest ride you have built. & i love the trophy truck . But this thing just bad ass & it schoots .
I have an old 1996 440 2 stroke 2 cyl snowmobile engine on an Artic cat that supposedly makes 60hp. You've inspired me to go forward on a golf cart engine swap project. Unfortunately im at the stage of -rather be learning to weld 😆
Awesome friend you got there. Turned the test into blaa into hell yea!
Engine sounds much better. Pesky plug wires. I don’t know how long the engine will last with the air intake situation. I’d look into some sort of snorkel so it’s not sucking dust.
Thank you! Favorite channel!
Sounds awesome in the end she rips
2007-2008 Polaris 600-700 cfi is the engine u need... Two cylinder "clean fire injection". Have lots of power
Don't change the engine work on the carbs fine tuning buddy ❤❤❤❤❤❤
I've had the same issue with my cross cart that has a snowmobile engine & after much testing & driving myself almost "Batshit Crazy" I built a baffled fuel cell to keep the fuel from being rushed all over the tank because of the torque "G forces" & i also put an inline fuel pump equipped with a pressure regulator & mine will pull in corners as well as straight line !! The jetting was not a real big issue other than the the power through the lower to top end power band !! Hope it helps you & you can get it ripping!! Also after you get the throttle 100% as opposed to the 3/4 like you showed that you had during your testing !!
See, genuis and what comes with a genius.
to get a more accurate reeding of afr i would put the sensor after the expantion chamber. Remember that afr is just a refrence number, not the bible. When i tune carb 2 strokes i'll tune after sound and feel, and then look at plugs to have it live at wot. To be completly shure the engine is happy, you need to learn to read the plugs. AS the brother dude is saying, fix the throttle cable first, then get it to run good in wot with the mains, and then dial in the 3/4 and 1/2 with needle and so on. Love this build to, and good luck tuning this thing. Old 2 stroke triples are known for beeing finneky to dial in, but so satisfying when they run good. And yes, that engine is made for running it on the side, upside down and straight up in a snowmobile with no problem, so drifting should not be an issue. Greetings front the land of snowmobiling North of Norway