How to Build a Competitive Kart Racing Engine (Stock Appearing)
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- Опубліковано 22 тра 2024
- How to build a stock appearing racing engine from Harbor Freight. All the tools and parts you'll need to take a non-hemi 212 Predator engine from 6.5 HP up to 18 HP.
This is my 2nd channel. For all the good content go here: / makesomething
**Engine Parts (Total $1184.16 before taxes and shipping)**(Affiliate Links)
Non-Hemi 212 Predator: bit.ly/38wk5sl
28.5 Intake Valve:
25 Exhaust Valve: www.arcracing.com/dj-1121-sta...
1:3 Rockers: www.arcracing.com/97-113bv-1-...
Retainers: www.arcracing.com/dj-1046t-ti...
Lash Caps: www.arcracing.com/dj-1051-hig...
36# Springs:
Cam: www.arcracing.com/dj-1104p-pr...
Flat Top Piston: www.arcracing.com/dj-1285ph-s...
Connecting Rod: www.arcracing.com/6252-arc-bi...
Long Carburetor Stud: www.arcracing.com/dj-1345-bsp...
Billet Flywheel: bit.ly/3GCpprK
Gasket Set: bit.ly/3ovVdGA
Push Rods 5.340: www.nrracing.com/product-p/cm...
Top Plate: bit.ly/3q7Tqbf
Fuel Pump: www.arcracing.com/fpc1-1-fuel...
Air Filter: bit.ly/3nAnk6a
Air Filter Adapter: www.bmikarts.com/Airspeed-II-...
Spark Plug: amzn.to/3gPgLvw
Chain Guard: bit.ly/2K1rRkq
Pre-filter: bit.ly/2XvFBXI
Header: bit.ly/38udRcs
Fuel Line: amzn.to/34TICYS
Carb: www.doverpoweronlinestore.com...
Valve Spacer: bit.ly/3hZk9Uo
2° advance key: www.arcracing.com/dj-2172-x-o...
**Tools Used**(Affiliate Links)
Plastigauge: amzn.to/3KQHBjP
Flex-Hone: amzn.to/3s8Ihdw
Piston Ring Installer: amzn.to/3Fb641P
Assembly Lube: amzn.to/3kABlBL
Ice Pick: imakeny.com/products/diresta-...
Piston Ring Compressor 70 mm: bit.ly/3s708Sk
Torque Wrench: www.harborfreight.com/38-in-d...
Cut-up Side Cover: www.ebay.com/itm/324345592716...
Dye Grinder: amzn.to/3LDPGJP
Crankshaft Stop: www.ombwarehouse.com/3-4-cran...
Valve Grinding Compound: amzn.to/3y7SXNk
5.5 mm Reamer: www.nrracing.com/product-p/880...
Valve Guide Hone: www.nrracing.com/product-p/bc6...
Valve Guide Remover: www.nrracing.com/product-p/079...
Valve Seat Pocket Cutter: Adjustable Range: 1 1/8"- 1 1/4" for 3/8" pilot. (Ebay)
3-angle Valve Job Tool: www.nrracing.com/product-p/new...
Spring Pocket Cutting Tool: www.nrracing.com/product-p/spr...
Valve Lapper: www.nrracing.com/product-p/pt-...
Valve Spring Tool (newer version): www.nrracing.com/product-p/vsp...
Kart Oil: www.arcracing.com/9806-lucas-...
Zink Additive for Break In: amzn.to/3F96lCi
*Stock Appearing Rules*
• Stock appearing Clone/Predator that must be pull started with a standard rope. No external compression release.
• No strokers. Must be stock stroke.
• No external billet parts. No billet side covers.
• No external mods.
• Must be a Clone or 212 Predator block. No Honda, Tillotson or other blocks.
• No head studs, no side cover studs. Must use bolts.
• Maximum 2.815 bore.
• Carb must be Predator/small block/Clone carb.
• Carb cannot have external mods including welding or epoxy on the outside to allow bigger bore.
• Choke can be removed and sealed
• No fuel additives. (methanol and gasoline allowed)
• No block bracing or head girdles.
• No aftermarket carb spacer between carb and head and cannot be vented or pulsed into carb or intake anywhere (valve cover spacer allowed).
This is the league I race in: www.idiotsracing.com/
Here is where I learned how to build racing engines
HP Academy: www.hpacademy.com/courses/lea...
Book: www.ebay.com/itm/262152692345
ARC: bit.ly/3F7cIWS
0:00 Intro
0:32 Predator 212 Motor
1:03 Engine Teardown
3:38 Connecting Rod
4:10 Piston
4:35 Crankshaft Clearance
5:38 Cylinder Hone
6:08 Piston Rings
8:32 Crankshaft-Piston Assembly
9:17 Camshaft
10:50 Block Clearance
13:15 Flywheel Assembly
15:08 Ignition Timing
16:56 Ignition Coil
17:27 Cylinder Head Disassembly
18:11 Valve Seat Removal
19:05 Valve Guide Honing
20:38 Cutting Valve Seat
21:24 3-angle Valve Job
22:19 Porting and Polishing
24:16 Head Milling
25:00 Valve Grinding
25:35 Spring Pockets
27:04 Valve Train Assembly
30:22 Roller Rockers
32:26 Finding Top Dead Center
34:43 Set Lash
36:26 Carburetor Assembly
38:25 Top Plate - Навчання та стиль
A little advice on checking the valves for leaks:
DON'T use water. I've seen so many people do this thinking that because water doesn't drip out the intake or exhaust, that there's no leaks. The reason you don't use water is because you're putting water on previously oil coated surfaces that are polished, which makes them slightly hydrophobic. With the surface tension that water has on that hydrophobic surface, it can float above small gaps and not bleed through. Instead, use a solvent like acetone, xylene, or even gasoline. They have lower surface tension, and will actively leech through any gaps or leaks in the valves. Hope this helps.
Well said
Yep! You need the most oil-eating liquid possible.
@@Kootwoot MEK! lol
Gasoline works very well. Never use water
@@austinrobinson186 are you trying to get cancer? Cuz that stuff is super carcinogenic! That's why they banned us using it when I was in the navy, aside from the fact that it causes hydrogen embrittlement on some metal(makes it weaker)
Man! This is GREAT! I'm a 42 year old automotive master technician and I had NO IDEA they made sooo many parts for small engines! You just opened a whole new world up to me! Coolest thing I've seen in years!
I'm a master technician super mechanic.
YOU SOUND PRETTY BAD AT WHAT YOU DO !
Those predator motors are popular among racers , and mud boaters .
“Master”😂
Master Og way 😂
When resurfacing a head with the flat glass/sandpaper technique, work the head in a figure 8 motion to avoid uneven material removal.
And a slight concave backing plate to get it flat.
This is one of the best engine build videos I've ever watched. If a person can quickly and simply explain a complicated subject then they actually know what they're talking about. 10/10
Alright, I don't have interest in go karting,, and I haven't messed with engine building for almost 20 years, but I watched this entire video because I follow your interests that you share via videos and the podcast. You have gained so much knowledge from when you started this hobby, which is really awesome to see. Your knowledge and passion is clear in this video. Kudos, and keep it up!
Thank you Chris! I always appreciate your kind words!
Guy has info I have not found in other channels
same here! not into small engines but this video is making me reconsider it!
💯 agree!
A
Qws31 God damn all right
im afraid you are now part of the automotive community and you may never stop making automotive content. Congratulations!
I used to be into yard carts in my early teens but haven't had any opportunities to play with them since. I watched this entire video from start to finish--man, what a great little intro to engine building! I've been a sub of Cars&Cameras for years, and have seen some of the stuff you've done on their channel, plus a bunch more from you now. Thanks for that. Really enjoyed this. Cheers~
When i raced box stock i took new head gaskets to a shop with a 300 ton press. I made 2 steel plates 2" thick , put the gaskets between them and reduced them to the minimum allowed thickness. It helped get that fraction of compression other builders didnt have. Every tiny bit helps as you know. Great video!
You are the cleanest mechanic I have ever seen. You rock Dave. “Some of us don’t have friends “ You always crack me up with your humor.
When you start with a out of the box engine and then drain it before starting your work on it - it is easier to stay clean. Run a few laps on dirt and then start the process and it will be a different story.
CLEAN... USE OF DREMEL SENDS SHARDS OF METAL AND ALUMINUM IN THE CRANKCASE BEARING..
Hey, I don't have any friends and I don't even have a life. That's why I'm watching Dave's life.
Ive been telling people for years to flip these small engines to lubricate them before the first start
Its good to see someone actually doing it
pull it over slowly a few times or pull it over a few times before actually trying to start it. Small engine or big engine - same idea.
When i first came across this video and had little to no experience with building or modifying these (or any) engines, I never got past the first couple of minutes.
Now that I have modified several engines and I'm always swapping or grinding something to pull that little bit extra power out of them, this video is way easier to keep up with.
I like the fast pace you've managed while being as thorough as this video is. One of the best clone building videos on UA-cam, and Im confident because I think I've seen most of them.
Great job.
Pretty cool! I built Hi-Po 'Lawnmower' engines in the 70s. Back then, the trick was to use Tecumseh engines (Forced Oiling) and we even converted some from vertical to horizontal flow, shaved the heck outta the heads and changed the oiling pickup. Ignition timing was adjustable on those engines as well. We used 5 HP camshafts in 3.5 HP engines and used two McCulloch chainsaw carbs on an Aluminum manifold. We started these engines on Gasoline then once warmed up, they were run on Methanol-Acetone mixture. Pretty heady stuff for a 15-year-old with a very smart Power Technology teacher and a small dynamometer.
how did you guys make forced oil in these engines you guys make your own oil pump?
@@ephenj Techumseh engines have an oil pump.
I started racing when I was 15 sprint kart racing (short course asphalt). It was a great place to learn to drive. Then I got into road racing karts. It was huge in the 80s. Every Christmas our family would race at Daytona. The smallest class I would run still had 50 or 60 karts. Some classes (usually Yamaha) had over 100 entries. It was the most fun times I had with my dad, not just the racing but the hours of preparation we spent in the shop and the travel to the races. It was all good, and I learned so much. It was a great way to grow up.
Thanks for bring back the memories, even though we ran two strokes 😜. Be safe and have fun 👍
That brought back memories of my younger days messing around with cars. I did the heads on a 1990 Thunderbird I bought for $500 while I had it parked on a jobsite I was working at 20 years ago, and that was the last time I did any serious engine work.
Now I'm thinking gas powered table saw...
:)
Awesome video, David!
John, a gas powered tablesaw is worth at least 30 million views!!!
@@SomethingAboutMaking have you ever been to Keim Lumber in Charm Ohio? I think they have gas powered table saws for the Amish
@@beaushaw I've been! That place is incredible!
@@SomethingAboutMaking Are you a mechanic by trade? Great video btw! I subbed.
Delta’s “The Modern Motor Driven Workshop” published in 1930 shows how to hook a gas engine to their table saw of the day. They even go so far as to show how to rout the exhaust pipe out the wall of the workshop.
I was an engineering technician at Briggs & Stratton and worked on kart engines as well as the dragster engines. Fascinating, I never realized the fanatical customer base for these engines.
Watching from the perspective of someone who grew up on an automotive machine shop, looks like you did a great job. You can build a flow bench and actually play with porting a lot more. There is even a way to smoke it and actually see the flow characteristics and what a subtle change can do.
The best way to check for proper valve sealing is with a vacuum pump. It’s easy to make a plastic plate (add a quick disconnect to the plate) that bolts to the head and use a MityVac vacuum/pressure tester and you’re good to go.
You are correct sir. It's called a leakdown test, and it does work well.
proper for a shop...you can use a solvent if doing yourself at home. guessing this is for the budget racer.
Thank you David for putting this video out. I have been curious about the process and this will be a GREAT resource in the future for lots of people. You first teased this on the podcast and it had me intrigued, great information throughout the video. 👍🏻👍🏻👊🏻👊🏻
Some very useful information here ....glad to see someone working with what they have and not using extremely expensive machining equipment. To me this shows you can do it with basic garage tools along with a few specialty hand tools. Thanks for a very detailed video.
One of the best comprehensive videos on UA-cam. You sir have your act together...
I am a retired mechanic that will venture into this world of the predator realm with this knowledge. Thx
Man I have never been into kart racing but I have to say I thoroughly enjoyed this video. From the detailed explanations to your fantastic cinematography and production. Absolutely amazing job with this video. 👏
Same here, took a huge dab and found this rabbit hole. This guy is super easy to listen to and watch and learn.
This video had top quality production value. Well shot, paced, and very informative. Kudos to you sir.
David, that was brilliant. You are an excellent teacher. I've watched tons of "engine" videos but this made it simple for me because there's only one piston to worry about. Thank you very much for that. New subscriber.
Came to this video by chance - was so full of knowledge and reminds me of 2 things - 1. A lot goes into these things, but 2. If one is willing to learn and put in the time, one can do this.
Highly appreciated!
Man, this is presented so well whether for a beginner or even someone like me who knows a ton about many engine types and is just getting into these. I wanted to know the reason why youre replacing certain parts for THIS engine so that was great!
Racers today do not know how lucky they are having videos like this. When I started in the 80s, racers would tell you a little & the rest was bullcrap. You had to get pieces from different racers and put them together to get the whole picture.
When I started in the mid-90's, the guys you were competing against would outright lie to you. The guys you may be competing against in the future would tell you half truths and everyone else would just ignore you. If you wanted to compete, you either needed to find someone that had stopped racing and was just there to "hang out" or find an engine builder that had drivers in other classes.
When I was building a jet ski engine in the 90’s you waited every month for the current issue of Jet ski magazine.
@@aaronthomas6155 or do engineering. Usually this kind of knowledge you have to pay for.. but with internet being what it is today engineering can be done in your garage with a few videos. I took aerospace manufacturing and aviation maintenance, so I understand the principles that make an engine pur exactly how you need it
@@letitbe90210 I've raced against mechanical engineers. They were great at building engines but were horrible at setup and reading a track or weather. Not everything can be learned on the internet. Somethings only come from experience.
Idk how yt brought me here, but as a mechanic that worked in a bikeshop and tuned engines myself, I was very pleased to watch this. You explain things very well for starters with no needed fluff or editing. Great stuff! Hope you have a great day good sir.
The most concise and detailed video on UA-cam for building a Predator engine. Thank you for taking the time to explain the steps that go into the art of building a race engine. You have a natural talent for teaching. I am a new subscriber, and thanks again for the information.
Wow, great video ! I raced a McCulloch 101AA long ago. I think it was turning about 9k rpm on nitro 9 and variants. Of course, that was old technology that has been long surpassed. I never completely re-built one, so watching this was interesting. Even back then, it was amazing just how much science went into better performance. From frame flex, carbs, clutches, carb air flow "shapers", exhaust, tire compounds and on... So I can just imagine what's out there now, compared to then. Thanks for sharing !
Sweet content dude! Watched your whole video! I’m an engine builder myself but much bigger engines. I learned to use fuel to check for leaks in the valve seats. I’m sure water works just as good. Keep up the cool videos and people will come.
Easily the best video building out a small engine ive seen and ive seen many you explained everything that you talked about explaining how and why you are doing this modification, well done
Nice job. The details were great but the racing video at the end is the perfect finale. Looks like a real blast racing those small karts in such a tight little track.
I have two karts and have always built my own engines and with the information from Jody and the awesome people at ARC, I've been very successful. And in my opinion your video is very good you hit all the bases without having to hear yourself talk like some do. Kudos to you, keep up the good work!
Jody Powell knows a this or 2
My wife wants to get back into gokart racing, she would've been doing races and shit when she was a kid but her dad started making excuses to take her. I'm getting it soon to rebuild and get her back into it. Definitely saving this video, you did an amazing job describing everything and explaining exactly why you make the modifications and their purpose for you. 10\10 my guy!
Depending on where you live, tires are a nightmare at the moment.
My dad always did the exact same thing. I would ride my go kart all day everyday when I wasnt in school. My dad would get my hopes up by mentioning go kart racing and I'd think that maybe he was gonna take me and let me do it but anytime I'd ask he would have some excuse why we couldn't. He never failed to have an excuse why we couldn't do something. I caught myself not long ago doing the exact same thing with my daughters and it made me feel bad. I have to learn to find excuses to do more things with them
Damn bro, you definately earned that thumbs up! From idea to running bike is brain shaking. And how smooth it runs! All yours bro. Amazing! One of the most ambitious projects I’ve seen pulled off on UA-cam.
Lapping sooo important. Glad you covered that. So many people think the key holds the fw in place.
This just popped up on my feed, and it's such a well done and organized video, you can litterally feel the amount of effort put in as you watch it. I decided to subscribe and go through your channel and you litterally do everything, which is so cool to me. Will be watching many more videos from you.
maybe it is you that is responsible for that abortion called the Animal.
Pull your torque wrench instead of pushing. You're able to apply more force easier. Excellent video, very efficient.
Pulling is the correct way to use a torque wrench. Never push. You are absolutely correct
I'm learning! Thanks!
I have been into karting since 1985 started in jr. stock and have raced Stock Appearing and Open Modified. It’s such a blast.
Informative, not overly technical, but touching on all the key areas of modification. Well done!
Those HF engines are no joke. I've been seeing them used in a lot of places, especially over similar Hondas. similar power and reliability for fraction of the cost. It's pretty cool. I'm debating picking up a Predator engine (non-ghost) for my kids' yard kart just to replace the finicky one that's already on it.
That sounds like a plan Dad.
I know so many people where if price is a big factor, predator is always the immediate choice no matter which version
Get the Ghost!! The extra few bucks is completely worth it otherwise the cart will sound like a log splitter
Get it, I put one on my daughters go cart and it does about 35 with me on it at 200lbs. Non ghost
@@brodieodell1974 I have to fix the steering before I worry about the engine. My oldest sent himself to the emergency room when he ran head long into a tree with it. No point in making it go if you can't tell it which direction to go.
The Ball hone achieves something akin to a sandpaper finish, the long chain hydrocarbons in the oil that offer lubricity between piston and bore get sheared quicker and the oil fails sooner affecting the rest of the bearing surfaces. Buy two of those 3 arm sprung hones, one with course stone and one with fine stone and build the hone finish properly. Piston rings are designed to hydroplane along the cylinder wall on the oil caught in the "deep" hone. The initial overlayed shallow hone atop the deep hone is meant to abrade the rings to a mating surface H7 fit. The light hone is at the same time abraded away to form plateaus atop the deep hone peaks, this is the breaking in process (breaking off the minor peaks). The deep hone valleys anchor the splashed oil till the rings shear through this oil then, hydro glide across the plateaus. That said the ball hone is a mongrel tool that doesn't deliver the engineered principles desired. Yes ball hones seem to work but not like the proper hone finish. When you're chasing performance (HP & longevity) for 7000rpm average make a torque plate and bolt it down to simulate the head, this will twist and bulge the barrel, the course honing will return the bore to cylindrical, reduce piston flutter and oil shear so more power. Apply the course hone with faster reciprocating action for a more acute (60/30) hatching in line with the bore to allow for easier oil shedding, the light hone can stay at 45. Coning the bore off perfect cylindrical 2-3 tenths larger at the bottom for reduced friction adds HP and longevity as the effective pressure is so much lower at the bottom and doesn't need rings shearing the oil to form as great a seal. The piston could do with an oil hole drilled through each wrist pin boss for better friction management so more power. The piston skirts narrowed give better engine acceleration and lower peak impulse load on the bearings, the piston skirts aren't cylindrical and examining an old piston will show the "contact" patch you can machine a new piston skirt upto. Finally turning the piston around will give you slightly more compression but more slap and wear, it's a geometry thing. You skipped over performance valve and seat prepping, guess that's where you've keeping true to promise.
I'll apprentice under ya
First, love the video! First time I've seen any engine builder go through step by step of what is necessary for a competitive motor.... for any kind of racing.
I can say that in the car engine world the rings vs. bore finish have come a long way. Very thin rings vs. finely finished bores etc.
The ball hone gives you the cross-hatch pattern which helps leave some oil on the walls. Then there is ring gap.... It used to be the bottom ring (3 ring package) was gaped smaller than the top. But apparently that leads to flutter on the top ring. Of course you want to go with the lightest piston (reciprocating mass sucks for power). Roller bearings on the cam.
@@confuse9 What's come along way is thermal management. What's changed is the compromise delta. As bores maintain cylindricity over the wider thermal range, manufacturers have reduced compensatory design (clearances for thermal change, ring pressure, film viscosity). Shorter chain oils, and lower spring pressures means lower drag so better (fuel tank) economy. This requires a very accurate ring on oil to bore calculation. Throwing a ball hone in modern, low ring pressure, engines cant achieve plateau requirements as it cant in older engines either. Look at Audi over the last 15 years and you'll find increased oil consumption rates as they chased the low internal friction delta. Audi's bore finish breaks in almost immediately and has the right ratio of scratches (valleys) per area for oil retention but not (**see service manuals and law suits) over retention. Best use for a ball hone is to remove grease and rust from a block prior to proper machining. Aging a block in the back yard or grabbing a high mileage block from the breakers is valid but really harsh on workshop machine tools. Emery taping the deck faces and ball honing the cylinders saves expensive carbide inserts from cutting abrasive oxides, that's a good use for a ball hone, as a heavy duty cleaning brush.
Been building for years, only now did I come across such detailed and invaluable information. Thank you.
I agree with you 100%. The cost and time to hone the cylinder correctly will add longevity and keep more HP longer. Definitely worth buying a set if you are going to build more than one engine.
My 9 year old and I are getting into our first build. I'm sure I will be watching this video for many years. Awesome job and SUPER helpful. Thank you!
Never looked at a kart or engine related video on UA-cam up until now so I'm not sure why I was offered this one.. but I'm glad I was! Excellent video I watched it start to finish replaying certain bits over and over. Thank you for your knowledge sharing and the way you convey it. Best of luck in your karting endeavours! ...I must look up this class I've never seen karts not on tarmac before!
If you're cutting valves after your lapping you can use blue daikum and it will show your high and low spots if you have any if not it will be a complete circle around your valve and you can see a good seat
I don't know why you waited so long, this is fascinating. I have no interest in go carts but I'll watch this all day.
Ha! Thanks Nick!
Thank you for the time and explanation !!!!
grew up with guys like this teaching me in the early 90s. its refreshing to see what i learnt way back when still be very effective today good work man.
This video was so well done, much better than everyone else who just says you need this part and it goes here, but never explain why or what it does.
As a machinist at a shop, what I recommend during the water leak test, actually fill the port and blow air against the closed valve. If you have air bubbles, gotta fix the seats 👍 Good video and interested in watching my work but on a smaller motor
Water has a lot of surface tension, kerosene or gas would be better for just a gravity test, but perfect for a 'pressure' test.
The zinc additive was removed from engine oil by the EPA in 2013. It's essential for any flat tappet or non roller lifter valvetrain. I'd use it past the break in.
Rotella T Triple and T6 both still contain zinc, the former in 1200ppm+ range.
This is the kind of quality content that makes UA-cam worth existing. Thank you.
I don't even have a kit car, but there is a kit car track track in my small city where I live. It's 2:00am after getting off work watching how to build a built engine for a serious go kart track.
Well done sir!
I will 100% watch every video like this you make. I love the mechanical workings and visibility of all the gears. Not to mention I love tearing down and rebuilding small engines like these.
Thank you!
This is super cool man! Been playing KartKraft in VR and would love to do some IRL racing.
Do it
Nothing like real life!
If you’re doing street course racing buy a Briggs Lo206. They run them about everywhere while the predator stuff isn’t ran anywhere I know of
@@dondelchulia3189 the Predator is gaining traction FAST so it depends on the region and if its "box stock & sealed" rules or not...you can build a BADASS predator for about $650 all in that a box stock $600 Lo206(Undressed at that) cant even compete with. And that can be upgraded even further without much more than a cam/spring swap. Around here, almost all Kart classes allow predator based engine....even some predator based Jr. Dragster classes are common at the strips around here now
@@Shadow0fd3ath24 He's saying Predator engines aren't ran around him because the racers don't choose them, not that they're banned.
Wow...Just a high school and college kid when I "built" a Ford 289 for my 65 Mustang and a Honda 450 DOHC motorcycle engine. Fiddled around with porting and polishing with a piece of plexiglass and a graduated cylinder from chemistry class. Your video is so detailed, practical, and precise I was remembering my youth and my uncle "MC" who was a master mechanic from a young age. Sure read a lot of "Hotrod Magazine" back then. I do remember a speedy "racer" gocart with a McCulloch 2 cycle engine that we rode around the neighborhood as kids. It made so much noise we got an unpopular reputation in some areas. GREAT VIDEO !!
I don't have a go-kart but love to play with engines this video was so complete i watched it from a to z.Thank you for taking the time to make this video. Even a noob can have a good idea of how a gasoline engine works.
Circlip tip (7:30): make sure the opening is facing up or down, relative the stroke. If the opening is to the side, at high RPM the G forces can compress the clip enough that it can come out. Overall an excellent video! I don't even race carts and this makes me want to build one. :) How do these things hold up with splash lubrication?
Don't ask me how I found out circlip location was critical.
@@mmi16 How'd you find out circlip location is critical?
And that's why I love Spiro Locks instead of Circlips for wrist pins haha.
When checking the valve seals you should use petrol or diesel, water is way too thick to test an air seal. Petrol will evaporate if left for too long so keep an eye on it
Yep....thats EXACTLY why you use gas! its a better indicator of leaks since its so thin and runny and water has too much tension.
A vacuum checker is the correct way to do it. The tool isn't that expensive either.
Yea we used acetone in my shop it’s super thin.
@@davelowets There's a correct way to do a lot of things, if petrol isn't leaking through however the compression is good. No one is buying a tool for a one time job, i certainly ain't
@@mrcaboosevg6089 Do the job right, or dont do it at all.
I don’t even have a go cart. I’ve seen videos of people working on things, you are at the top in all categories.
Excellent Video!!! I love the pace, not boring at all.
Wish I had someone like you around when I'm building.
“Some of us don’t have friends” That really hit home
Commonly I see isopropyl alcohol used for checking the valve seal before the first heat cycle, but always remember that if you have teeny tiny itty bitty leak, the chances of it sealing after running for a break in are almost 100%
I second the isopropyl alcohol...
Alcohol's for drinkin', lighter fluid's for checking valve seats 🤣🤣🤣
Thank you. Your way of showing how to, is the best ive seen yet. Learned a lot today!
Really love the explaining everything in detail. Someone like me has general knowledge, but has never taken part of motor feel after watching your video could tackle a job like this 😎
I don't race, but this video makes me want to modify my lawn mower engine...
Great video David! I'm a FAA A & P, , and I'd like to share nothing happens without "ignition". I hope you'll find the aviation version of the internal combustion cycle to be more accurate. Which is: 1) Suck, 2) Squeeze, 3) IGNITION, 4) Bang, 5) Blow. Great tech video, , you point out ALOT of very good tech points and assembly processes for high output engines! Lastly, you have really good production (sound, lighting, layout and editing) values. Loved it!
Aircraft engines don't operate on the 4 strokes, intake, compression, ignition, exhaust?
@@genefogarty5395 Gene, yes they do. Please reference any aircraft mfgr's piston or gas turbine engine operation discriprion. You are misinformed or do not know the facts with gas turbine or high bypass gas turbines. These are commonly called "jet" engines. . I'd recommend reviewing the Continental IO540, a 540 cubic Inch "Opposed Piston" with ovhd vales. Or the Pratt &Whitney 4000 GTF (Geared Turbine Fan). A typical jet engine has multiple rows of compressor blade. Then multiple rows of blades in the "hot" section. The air enters a typical gas turbine and is very highly compressed. In some engines it's compressed from static atmosphere pressure of 14psi (sea level) to >200psi. in the "Compressor" section. This very compressed air flows into the hot section. Kerosene is injected at very high pressure and inside this "hot section are "IGNITORS". There are two types of ignitor systems. The continuously "sparking" ignitor or the continuously "Hot". These "ignitor's" are needed to ensure that the kerosene gets ignited in a very high pressure and very, very turbulent gas flow! This flame front then expands the pressure in the "hot" section by 5X or more! This pressure then expands as it flows across/through compressed hot section blades, creating a massive pressures and force. This gas the exits the jet engine via a third set of compressor blades called the "Re-Heat" stage. So, in a nut shell, it's Suck, Squeeze, IGNITIO, Bang, Blow! I hope you have benefited from today's class. All the best, TAC
@@WestKyCrime This was a 4 stroke ICE, not a jet, dude. It's still intake, compression, ignition or bang as you call it and exhaust. Ignition and bang are one and the same. There's no delay, it's an explosion. But thanks for the "Class"
@@genefogarty5395 sure, we all have our opinions. Let's walk thru what happens in a ICE ignition event. And I'll try to see if I can convince you why Ignition is its own "event" in the ICE operating process. The crankshaft magnet on the flywheel (engine in the video) passes by the stepup voltage transformer. The magneto (AKA a very strong magnet). The step up voltage coil then excites the main voltage step up transformer (AKA as a "coil pack"). Once the voltage exceeds the ignition systems regulator (AKA as a special type of capacitor), this high voltage then seeks a path to ground. And "wah-La", it's ignition time. Bang occurs AFTER this above ignition event. In closing, I bet you will agree, that the first thing experienced technicians ask when trouble shooting a ICE is, "Is it getting Spark"?. Next question is likely "is it getting "Fuel"? So, I hope you can now agree that "Ignition" is its own event in Petrol ICEs. All the best Gene.
@@WestKyCrime It's a 4 stroke. If there's no intake air coming in it won't start, no compression, no start, no spark, no start, no exhaust going out, no start. Pretty simple.
Awesome! I learned more about engine building, building any engine, than I've learned by osmosis in all my years of working with gasoline engines. Excellent material. A Master-Class in engine building.
Man you hit everything right on the money!! Very impressive, very inspirational and your very detailed on everything and straight forward with everything! Thank you for your great knowledge on these motors. I’m super surprised you don’t have a billion views on this 😂 once again thanks bro 😎 you’re the man!
7:43 With a Trabant engine the entire cylinder is a piston ring compressor, it's tapered and installs after the piston to the block. Off topic but just realised how neat it is
Excellent overview David. Most pro shops have a vacuum pump attached to the seat and guide machine, and they hold a cover over the intake or exhaust and pull vacuum on the port to see how the valve seat seal looks. You have the right idea on using a fluid for an easy check, but water has to high of surface tension to flow through any small space that would be between the valves and seat. Typically I use alcohol or acetone, but if you do not wish to use a volatile fluid, just mix some dish soap in the water and your test will be much more effective. Bravo on the video, I have been interested to see how you tackle such a large topic in one video. Best of luck with the racing in 2022.
Ohhh! Thank you! That's good know for next time!
A head can seal just fine when hot, and not seal at all when cold. Depends on how much the geometry changes with temp. There are a few race care cylinder head shops that heat the heads and run hot water through them during the valve job operation for that reason.
Wow awesome build and great advice! Thanks for keeping the spirit of competition alive!!
Thanks for sharing this. I have been looking at cyclekarts and this is very useful. I was always taught to do figure eights when lapping the cylinder heads.
Just a question: by changing the connecting rod and piston, as well as removing material from the crankshaft, wouldn't the crankshaft require rebalancing to accommodate the changes especially since it will now be turning at 8,000 rpm?
Possibly but I have not had issues
You have to remember that these motors are a single piston motor not a traditional motor with 8 cylinders that spin the crank at once. So take the side cover off of a motor and turn the motor over. There is only one point where the motor is perfectly balanced and that is when the crank is completely in line with the rod and piston. The other 99% of the time the crank and counter weights are not going to be in that position. I hope that was easy to picture in your mind. But to answer your question plainly no you never have to balance a crankshaft in a single piston motor. The only thing that you really should do is make sure the bore is true.
@@JakeSeiner That was a fantastic explanation. Thanks Jake.
@@SomethingAboutMaking Another tip that people don't really let out is call JC Specialty up and order hardened side cover bolts this keeps the side of that block from flexing with those oem bolts. I know it probably sounds silly but it adds a substantial amount of strength to a predator block. Considering that predators are the weakest blocks of all the clones this is a must for every one I build.
@@JakeSeiner well excuse my ignorance. Just assumed swapping out stock heavier con rod and piston for lighter components would require balancing, especially taking an engine meant to rotate at lower rpm's and pushing it out to 8k. But I have never souped up a lawnmower enigine.
I'm not an expert, but wouldnt dremeling on the actual crankshaft throw it out of balance? I get clearance-ing the case, but not the crankshaft. Your video was very informative and helpful. Thank you
I've been building these for a couple years and haven't had any problems with it. You do feel it on a minibike though, much more vibration per rotation opposed to an our of the box crank but on any application your not directly on I think it's fine.
the billet rod and piston is already heavier than the stock stuff so that little bit of grinding near the crank pin would actually help
@@xerolift good point, didn't consider that.
i know a little about engines and i stumbled upon your channel and i love it ! thank you
Man your awesome I have been looking 3 years for videos like this I enjoy restoring and creating modified go kart people throw away, I bring back to life
You are watching my 2nd channel. I don't post here very often. Check out my main channel for all the cool builds! ua-cam.com/users/makesomething
To check valve seal I always used brake clean (thinner than water) and used a air gun and a rag to "seal" and look for bubbles. Not sure how correct this is but I've identified leaky valves this way
the bearings will love all that metal shavings from the milling.
How much you charged to get one build man
Is that drill Festool? Looks like it but doesn't sound like it. I've been using mine daily for almost 15 years. Incredible quality. Thanks for an interesting production.👍
Did you grind on your crank shaft? Doesn’t that create harmonic imbalances?
I will never build my own engine/cart. I will probably never use this knowledge in practice but it was nice 43min with you and even as I'm non native speaker I had no issue to follow what are you doing and why. Great job. Thanks to people like you, the internet is better
Some of us don’t have friends….😂
I don’t have a kart but want one…recently started seeing these harbor freight engines popping up in my feed…the WANT is high! So much to learn!
New sub....anyone that explains a process so well and clear with no fluff means they completely understand what they saying great work good video thanks
That was a great ending building video. I used to build those engines for a friend who raced. I did not know all those cylinder head tricks except for stiffer springs and milling the head. I started safety wiring the side cover bolts cause of a failure where they loosened and ithe engine blew up. He had the same header as you, I wrapped that with DEI header wrap to prevent burns. I made a tool for holding the crank to the block for torquing the flywheel nut. For removing the stock flywheel I drilled and tapped the stock flywheel 3/8 nc and used a steering wheel puller to remove it. The same steering wheel puller with different studs would remove the ARC racing flywheel.
I do Most of this when I build stroker scooter engines and alot more little secrets. I'm old-school kart builder but we only had flathead engines back then, but we went over and beyond of what people thought was impossible back then alot of secrets Lol. This is a very informative/awesome video for anyone that needs a little more kick on their mini bikes or karts.
Respect for diving into a subject, parsing the info, and presenting it in an easy to understand medium.
::side note:: I bought a dirt bike when I was 15, disassembled it to repair, and never got it back together! 🤣
Nice to see manufactures step up. When I was a kid we had to make our own stuff. Had a few flywheels disintegrate on me which is why we has scatter shields.
Basic beautiful engine tuning. Great video mate
Great video, have not built a small engine in over 50 years but love how you explained things to everyone. The video did not seem that long to be honest, excellent content! 👍
When checking if the valves are sealed use to use Red or Blue Diakim (spelling maybe off sorry) as well instead of using water I always have used alcohol on all my heads with V8's or Air Kewled VW engines! Happy New Year! ✌
Grest vid ...lot of good info,and it is cool to know that these parts and tools are avaliable for this engine. . Takes me back to my early teen building fixing and modifying B&S 3hp engines for our mini bikes.
I have no need for a "competitive kart engine, but what a great video, clear and well edited. (Two stroke tuned scooter fan)
You know what? You do an excellent job in every aspect of a how to video. Probably why you have success in the other hobbies you do. I wish you luck in your races!
Just ran across the video by accident. EXCELLENT!! Informative and well presented. I am currently building a 1776cc VW Type 1 air-cooled engine for a replica BUGATTI Type 35. The VW Type 1 engine is just an "oversized lawnmower" engine (LOL)! EVERYTHING that you did is the same approach. REALLY ENJOYED the video!!
This is a really great video. That's a cool engine build. I'm going to be pulling the engine apart on my dirt bike as soon as I finish my latest woodworking project.
i like that your going through all this. back in the early 2000's i used to race a class that was based on the briggs animal 6.5hp. It was an open class, the only requirement was that we had to use the briggs block, everything else was fair game. At one point we had a dome piston, roller rockers, custom cam, and even had machined the head to accept valves from a honda civic along with many other things done to the head. made almost 50hp. raced on a short flat dirt track, if you can imagine we ran a 11thooth on the clutch and 68-70tooth sprocket. I would say our most reliable versions of the engine had flat top pistons and briggs valves with mainly a worked head and custom cam making about 30-35hp. Our big engine does hold the lap record though.
Wow! I'm not into karting but what a well made video. Great filming, narration, and pacing. Bravo!
VERY thorough.. I learned what port and polish was... great vid!
I'm just impressed there are so many after market parts. Nice
A tip I picked up from somebody that rebuilds motorcycle engines is to build yourself a small open square of wood out of two by fours or maybe four by fours and the engine case will sit on top and inside the square and not move around so freely on a flat bench. It’s sort of hard to explain but in essence it’s just an open square of wood that’s tall enough to allow the engine case to sit proud of the bench top. It’s so simple when you actually see it but I never thought of it myself. It really keeps the case from sliding around on the bench.
Great video! I learned so much from your engine build video. Have a great weekend and Happy 4th of July to you and your family. Wishing you many more race wins. Cheers!
What a great video. Thanks for tsking the time to make sonething so great. You did an excellent job deciding when and when not to explains things or processes. This video flew by 👍
This is an awesome walkthrough of all the work that is involved, thanks! It’s crazy that the rocker you installed costs more than the stock motor, gonna have to save up before jumping into this hobby I guess
Very good video! I work at a small engine shop and fix customer equipment and lawn mowers. Been thinking about building a predator for my coleman minibike!! Very informative!