I guess I'm like allot of "Old Dudes" that watch. Yes I'm close(r) to 60 years old than I am to 50. I like Ike also have a soft part in my heart when it comes to old "B&S's". It's what we grew up with. It's what we used on just about every conceivable contraption we could come up with or actually build. To allot of us "Ol' Timers", a 5HP B&S is something akin to a Chevy 350 CID. Easily obtainable, fairly cheap, easy to work on and repair, there's all kinds of alterations you can do to one so the outcome is "something near" to what you wanted. Yes Sir, you can go "new school" and get just about what you want right off the shelf, but (to me) there's nothing like spending a week-end out under the garage awning, getting grease under your nails, sweat in your eyes, skint knuckles, and the satisfaction of hearing "your creation" pop to life on the third or fourth pull. Love and enjoy the videos Guys!!! Keep up the good work!!!
Longer skirt keeps the Piston from rocking in the cylinder. Allows for tighter clearances and higher rpms. Being able to run a tighter clearance means the extra ring is no longer a necessity. Also having the wrist pin closer to the rings creates a more even force on the Piston as it's moving up and down by applying the force closer to where the Piston comes in contact with the cylinder wall. Having it lower would push the skirt into the cylinder wall during combustion causing excess friction and loss of rotational momentum, ie loss of power.
@@CallumTapper shorter rod, reduces (can't remember technical name) the flexibility of the rod and general stresses on the crank and wrist pin by reducing the mass as well. To be fair a shorter rod also increases friction since the angle it has to take is much greater. Realistically this means that if you're running weak components a short rod will be better but under ideal conditions with better components a longer rod does perform much better at high rpm, just don't bannana your rod.
@@dannycalley7777 Also, the longer rod means slower acceleration/deceleration stresses on the whole reciprocating mass, giving it more revability and power.
The reduced compression height of the piston (the wrist pin being up higher) allows for the longer rod which in turn reduces rod angularity improving the engines ability to not fly into a million pieces at higher rpms. This is also why most stroker motors don't spin up as fast as engines with shorter strokes. The longer stroke with the same length rod increases rod angularity. Essentially more rod angularity will reduce the engines ability to spin at high rpms but can net you some low end torque. Less rod angularity will lose you some low end torque, but allow the engine to spin to higher rpms allowing it to make more horse power.
It doesn’t have reduced compression. If anything it has the same or more. Issac, it is nice to see that someone else watching actually understands engine performance!👍
Also, the lack of one compression ring reduces the drag of the piston thus decreasing internal friction. The downside is the smoking. The lack of one compression ring allows more blowby into the crankcase which increases the pressure inside the engine. This is why the oil is being pumped past the oil ring. Perhaps a better crankcase venting system would relieve some of the pressure and reduce the smoking? Worth a try.
It's absolutely amazing to listen to someone who knows his Ka Ka. I built a go cart when I was 13, that was in 1953 Good for you guys..Looks like a blast. Brought back memories. Thanks
13:49 "that you'll never be able to find parts for..." From my rather limited experience, the majority of parts from these old flatheads are still manufactured by _B&S._ Not only that, but these engines were produced in such large numbers that it's really easy to find a "spares engine" for sale on the local classifieds. There is quite a lot of aftermarket support as well (ARC makes a ton of parts for 5hp Briggs engines), and UA-cam is awash with people doing all sorts of crazy stuff with old Briggs engines. Just my opinion...
Briggs 5 horse flat heads were the predator of there day. And parts are easy to find. The problem they do have is that the compression realise is a extra lobe on the cam shaft so when they run they loose compression and the only or the proper way to get around the problem is to grind down that extra lobe.
Brodie Bennett your right I only work with flat head Briggs engines and parts for them are so easy to find just look for the engine model number go to Google and look up preformance parts for the engine code ....
As I understand it, the longer rod causes the piston to “dwell” at TDC longer as it changes directions in its travel. It causes cylinder pressure to get higher. So good for more power. Thing to look out for though is with higher pressure you have more heat. So engines with a longer rod could me more prone to knock on cheap gas. You should be fine with that optima fuel. Hope this helps.
I agree with ike. Ol briggs have a soft spot. And yes the parts are alot harder to come buy. But dang they perform. Worn out rings and a bad valve guide and still picked up 5mph and 2 sec.
I grew up doing exactly what you guys are doing. I love this channel, it reminds me of all the fun I used to have. You've rekindled the flame. I'm gathering old busted up tillers and snow blowers and once the summers here I'll be building a cart. I'd like to see a vertical shaft engine cart build. I'd like to see how y'all setup the gearing.
Sorry John I'm with Ike on the 5hp Briggs, it's the engine that started it all for us when we were younger. But agree with you on the predator engine if your just starting out with no mechanical knowledge etc. Build a dual Briggs rat rod with a wheel Barrow tub or something. Keep em coming guys!
First off.. you guys are awesome. .. now about the smoking piston. I had a similar issue with my car pistons. They were aftermarket and the oil ring drain holes were not enough for my high reving engine. They only had 3 holes (6 total) on ech side of the piston. The stock had 5 holes (10 total) on each side. I drilled 4 more holes on the piston, being careful not to damage where the oil rings sit, this allowed the oil to drain back into the block easier. Since then my engine does not smoke, oil last longer and is less contaminated. Be careful not to hit the pin that holds the piston to the rod. You will have to drill at an angle. Good luck gentlemen.
Great job, guys, and lots of fun. The nice thing about old engines like that is you can find them for free...or close to it...if you keep your eyes open and are willing to elbow grease it back to life like you all did. My favorite part of this build is the front-engine-rear-drive configuration you used. It's effective and unique...as karts go anyway.
The hone you used is for brake parts. The longer stone in a piston cylinder hone guide it holding it true to the bore, your cylinder is no longer straight. More than likely egg shaped. It will need a new sleeve. Valve guides are also in the same condition. The piston is a forged piston Made for high rev's and compression. Able to withstand hotter burning fuels. You need a new block.
@@Hermiwalle Briggs & Stratton does not use replaceable valve guides. The amount of Machining that it would take to install them, it's not worth the hassle.
I think when you find an old flathead, it throws you right into tinkering and getting to know the mechanics of an engine (for beginners) and you can find something that runs for 50 bucks if need be. I love the front engine, live axle, drive shaft builds. I think another "rod" build with a 420cc, and maybe some sheet metal work could be very very cool
I am 53 & when I was a kid all we had was Briggs & sometimes the odd Tecumsay , had a 3 horse briggs on my choppered mini bike , & loved it . I love Briggs but a brand new predator works too .
I love the old Briggs. Gotta give respect to them because from my childhood in the 80's it brought so much fun to us all and it was about the only performance era engines we had at the time. So me id love to see more of them being brought back to life and keeping the good time rolling like the old days
I'm with Ike on the Briggs. I won't claim to have any knowledge of go karts but at least on lawn mowers they are pretty reliable, and very fun to work on.
I really wish you guys would pay more attention to proper ackerman. Almost all your builds have the ackerman backwards which is why they don't like turning. the inside tire should have more angle than the outside tire going through a corner.
differences in a standard, and racing piston, weight, alloy type, change in compression, ring design.strength these are the basics. The longer rod you have is to increase the time the piston dwells at TDC (helps with low and mid range power). The single ring lowers the drag on the pistons travel.
Older Briggs are way better then today’s engines by a long shot there way more durable then anything built today I’m a Briggs fan by heart they have never let me down. One cold winter I went to start up my tractor that had an 1976 8hp briggs been sitting for 2 weeks or so and I kid you not I took two pulls and it fired right up them engines I have a lotta faith in them.
My friend and I race open wheel mod dirt track car we run alcohol and boy does that stuff ruin anything that's not steel we have a shut off at the tank and have to let the engine run its self out of fuel. Then we fill the vent tube right away with pump gas or else you will have to rebuild the carb and fuel pump from sitting even overnight or 2 days. Also, the skirting on racing pistons are typically taller for piston slap which can crack them eventually it keeps the piston more straight up and down in the bore since shit is not built like it used to be you pull apart a brand new bred and butter car's engine the skirting is super short for MPGS and weight savings on the rotating assembly. Diesel engines have much much taller piston skirting for higher compression after all they all knock naturally. If you ask a regular engine to push more power for extended periods of time you will find with a micrometer that the cylinder walls are egged chopped more than normal
Not the cheap Briggs that don't have an iron liner...they last 200 hrs tops. Also, flatheads run hot and go through valves like crazy. Older doesn't always equal better.
totally disagree with you flat heads are far better then newer motors if you can get 35 hp out of a 5 hp flat head I will take it all fucken day long!!!@@T..C..M
I have a 5 hp briggs from 96. The only problems have stemmed from me not replacing gaskets. And an incorrect coil gap (found out when it stalled and had no spark) Although it doesn't have a cast iron liner it still is amazing
I've gotten 3 Briggs and Stratton flathead engines for free, that's how easy they are to come by. One of them is on my custom homemade minibike, you can't go wrong with an old Briggs. Also, they are a little easier to fix than any new overhead valve engine and parts are still super easy to find, these engines are where I've learned my basic mechanic skills.
l'm Ashley Smiley I live in Hazlehurst Georgia , being I'm 73 years old I guess I'm consider the old school guys. I raced carts for a few years and built my own engines and it sure would make you feel good to see it out front. the wiseco high compresion pistons, heavy duty rods,weber cams and a little carb work running on methanol. I enjoyed your show and looking foward to seeing it again
When you can get 15+ hp from a 5hp briggs I'm good we raced carts & built briggs with top straps on the motors to keep the heads on them they made massive hp with a few custom tweaks for internal piston weight & flywheel timing advancement etc !!
That looks like a 4.5 inch rod. If you measure from the center of the crank bearing and center of the wrist pin bearing you can tell. Then a matching piston compression height (0.590) I believe for the 4.5 long rod, and bore size. ARC racing has a page on there blog about calculations for all that. And you can get reamers and valve guide installer tools and Briggs valve guides on Dynocams and some other sites. And as for the racing pistons compared to the stock Briggs pistons, the racing ones are forged or billet aluminum to handle the higher rpm. The stock cast Briggs pistons won’t hold up long past 8,000 rpm. And with forged and billet pistons you run a bigger piston to cylinder wall clearance, because the metal is denser and will expand more in heat compared to a cast piston. It would be cool to see you guys rebuild this engine with a new piston and rings and show installing valve guides.
I hate to say this Jon but that lil red flat top is what started all the fuss. Everyone was always trying to beat a Briggs and couldn’t. The old Honda’s made a good showing but it’s that name that made him strong!
the longer skirt is to help the piston from wobbling to much and some times the rings width is smaller and the ring gap can be bigger or smaller. happy to help and teach you about that. BTW I am 15 hahah good luck guys.
High compression pistons (racing, "High performance" pistons) give the engine a higher compression ratio by bringing the stroke length up with a taller piston, tall enough to increase compression ratio, but not too tall to start smashing into valves, or in your case with the flat head, the cylinder head. More compression, in turn makes more power. Hope I was of education, love the videos.
I absolutely love your videos, I have learned a metric shit ton of information/tips/ideas etc, please keep them coming. You guys should have a tv show. My only complaint? Watching you guys turn laps on these unsuspended rigs makes MY back hurt! I have literally found myself bracing for bumps and grimacing when you hit them ! Great stuff
Briggs & Stratton 206 crate engines are factory-sealed long blocks with ground cams and controlled piston pop-up (reducing compression variance). These budget-friendly mills feature a simplified IKF/WKA rule set designed to maintain a stock configuration, right down to the factory-shipped carburetor jets. Simply put: the 206 engines even the playing field so that drivers can focus on the important task at hand--winning the race! Briggs & Stratton 206 crate engine features and specs: * Primary use: Karting, Microstocks, Jr. Drag Racing * Engines are assembled by hand in Milwaukee, WI using tooling and dies specifically designed for racing for unparalleled repeatability * Reinforced, cast iron sleeved, dual ball bearing racing cylinder * Single cast, custom aluminum alloy cylinder head with high-flow intake port, custom seat/guide material * Squeeze cast, T-7 heat-treated aluminum rod with reinforced I-beam * Carbon steel crankshaft with induction-hardened, micro-polished, crankpin-reinforced timing gear * Cam ground, barrel-faced, eutectic alloy piston with 3-piece ring set with chrome faced top ring * .255 max. lift ground cam with nitrited lobes and built-in mechanical compression release * High-silicon, racing-engineered valve springs * High-grade stainless steel dished valves with nitrited exhaust * 3-piece, automotive-style keepers and reinforced rocker arm and lock ball * PVL digital ignition with built-in 6,100 rpm rev limiter * PVL steel hub, cast aluminum flywheel * Briggs & Stratton tooled 22mm round slide, fully adjustable jet carburetor * Custom graph oil composition head gasket
The Briggs flat head is a great engine. Modified Briggs and Stratton flatheads are used in almost all oval track go karts and you can make those engines rip. There’s also still a lots of brand new parts you can buy for it online
Looking at the 90 degree gearbox on this kart. Have you guys thought about using a lower end of an outboard boat motor? Not only will that provide a forward-reverse, but should also have a long input shaft instead of having to build one from several pieces.
Racing pistons typically are higher compression, more sturdy in the cylinder as the skirt design makes them less likely to wobble side to side, and they often are made either by being forged or CNC'ed instead of being cast as well as they could be a special alloy that makes them stronger and able to handle higher combustion chamber temps.
For many years Briggs was the primary engine in small power lawn equipment, and it still is a big brand in that business, although the new OHV engines are a different thing from the old flatheads. If I was doing a rat rod with a red wagon base like that I think I would extend it so you aren't cramped up so much, a bit more leg room would be nice. I had one of those wagons when I was a kid in the 50's.
Great show guys but yea do more rat rod shows really love the strange builds the wagon was awesome and i love briggs you gotta give them props they have been around for awhile love them
I agree with the look Issac is giving you John, you cant go wrong with a old school flathead briggs. You can beat the snot out of them and they just keep running plus they are extremely easy to work on.
There is a L compresion ring and that helps whit getting more compresion because the L ring is higher on the piston then a normal ring so you get more compresion
That's been tested, thickness of ring. Friction verses sealing ability. A ring 1/8 inch wide will seal equal to a ring. 3/16 wide. On small engines the oil control ring is omitted on forged. pistons because due to heat the ring gap is wider, allowing oil to gather between the rings.
The Briggs & Stratton engine is like the Flat-Head Ford of go-cart engines. It has a cool factor the newer generic chicom clone engines lack. The Briggs is a perfect match for the Rat Rod Radio Flyer but I hope you can do a full repair of the motor with new rings and valves to see the full potential of this hopped up B&S.
Years ago, I built a 5hp Briggs like yours. Except it was built to the max! ,140 overbore with a Wiseco piston, a .300 stroker crank, full race cam, with a diaphram carb, and a stud and girdle kit to keep the engine together! @.140 overbore hte cylinder walls are pretty thin! this beast while it lasted was Dynoed @ 25hp !! had to reiforce the frame as well !!
Hey guys, when youre doing a hone, slowest speed on drill and up and down as fast as you can go. The idea is to make crosshatching on the bore to retain the oil. As for the racing piston, idea is less friction and less reciprocating weight to gain the higher rpms. The small amount of compression lost by not ahing a second compression ring is more than made up for in the higher rpms. The skirt shape and design is to support this. Great video. I must say.. id love to see the ducati engine on the drag rail tho.. ... .. cheers, Levi
Most oils today have detergent in it and if the motor inside was dirty from previous build up it will clean it and cause it to turn dark. Also once oil heats up especially on a air cooled engine it can burn it black quickly or if the rings are it can cause that also.
Assuming the stroke is the same as stock, a longer rod on a shorter piston will provide less side loading on the cylinder wall and should (in theory) cause less friction and therefore less wear and quicker rev. It also provides a less abrupt change in direction when the engine rolls over TDC and the piston starts to travel down the bore which also helps with better revving. Best analogy I can give is when you go with a 6 inch rod on a 350 as opposed to a factory 5.7 inch rod. But again, you have to go with a different piston dimension otherwise you just made a stroker. As far as the single compression ring, I'm not sure the purpose of that. I prefer 2.
Morey's oil stabiliser or Lucas' works very well! Racing Pistons typically have less rings to decrease piston to barrel friction; It allows the engine to rev more freely and make it more responsive. The downside is that there is more pressure and heat the single compression ring has to handle as opposed to running 2 or 3 rings, so it will tend to wear out faster than a conventional piston and ring set
Guys , we would like to see you build a cart from scratch ! Race frame and a dirt bike engine !! Yeah !!! Or even a old two stroke triple ?? Yeah!!! how fast can you go ?? Big Balls needed for that !!
my first project was an 8 hp briggs and i had no problems it had broken bolts, broken govener, valve job needed , bought new carb and it runs like a dream
I grew up with those old Briggs & old Tecumseh flat heads. They seem to make far more torque than the Chinee ohv motors of today. That ones already got the dual valve spring setup so the valves won’t constantly be floating once you hit 4500 rpm or so. As for the setup...the piston is lighter, longer rod likely means the builder is likely running a 3 1/2 crank for a shorter stroke coupled with a high lift, longer duration cam. Mic the cylinder to find out if and how much she’s overbored, get a set of rings if possible or a piston & rings...replace valve guides & seals. Add some timing with an offset flywheel key, dump some 112 in her & let her eat. Ya may also want to run a tighter clutch spring to get the r’s up before she locks.
The longer crank creates more throw due the extended stroke. This allows for a shorter ignition period and greater compression at high rpm. It allows the motor to pull greater throughout its entire powerband.
I disagree about not staying with a b & s engine. Back in the 90's,my buddy had a 5 hp briggs on his go cart,he raced it into the ground,hitting jumps,doing donuts and climbing hills with both of us on it. At the time the engine was old and it still ran like a clock. The Tecumseh was also a good motor but you always had to mess with the carb on them for whatever reason. As a matter of fact today he probably still has the go cart and I bet it would run.
The long rod setup reduces side loading of the cylinder walls as well as taking stress off the rod itself. It makes for a straighter line between the wrist pin and crank.
What makes the racing piston better isn't the piston itself at all, but its the ability to put a longer rod in. The longer rod is more durable, creates less side loading of the piston in the cyl, also makes the duration of time the piston dwells at tdc longer to get more complete combustion. See what Smokey Yunick had to say in his books about rod length.
Never stop a hone in the cylinder. Also move the hone up and down evenly in the bore and try to create a 45 degree cross hatch that will hold the oil in the cylinder and reduce ring wear. Remove the hone with it still spinning so you dont end up with your crosshatch horrizontal at the top of the bore
I've seen videos of guys getting sucked into machines. Shit is fucked up. The motor doesn't care, it will twist your leg into spaghetti, and maybe suck your torso in too if it doesn't sever your leg off first.
ha ha good stuff! The first engine anyone starting out should learn on is a 5HP Briggs bar none. You can find them in any old machine, simple design, easy to work on and understand how engines work. Just my 2 cents.
A longer rod changes the angle of the rod to the crank, its straighter, giving more leverage on the crank. Also gives a longer dwell time at the top and bottom of stroke. But also changes piston speed up and down the bore, this can be a bad thing with the standard camshaft duration and lift as it lessens the initial vacuum when the valve starts to lift which will affect the overall cylinder filling. My experience building race Briggs motors I stayed away from longer rods and race pistons. Longer rods cos of the intake issues and pistons due to reliability issues. Here's all you need, mill 0.020 thou off the head. Clean up the metal around the guide and the tricky one! 0.025 thou off the base circle of the cam, don't worry about the nitriding, if the followers are set right its a non issue. Polish and shot peen the stock rod and new bolts. Ran those suckers for 24hour races, won everything.
When we were racing gokarts, I used to swear that Briggs was developed by Chevrolet engineers... "If it ain't smokin', it ain't runnin'." ...at least not running WELL, anyway.
Awsome vid...theese are the kinds of things that we miss out on when we get caught up and put the wholesome life aside. This is a great way to slow down...think of the 8mportant things in life and enjoy...at leat for the ones like me that love to hold a wrench...God bless every one and thanks for the vid.👍
I'd love to see that engine restored to it's former glory, at least performance-wise. I agree with John on all his points, but there's just a certain charm to sticking with something old-school and having fun with it. As far as what makes a "performance" piston...in the case of something like this, it'll almost always be lighter, sometimes have one less compression ring (less friction), domed for higher compression, the skirt is usually taller, etc. You might have to re-sleeve that block, and if the valve guides aren't serviceable, then the block isn't worth saving. You'll likely be better off taking a good used block, sleeving it for that racing piston, and swapping over all your good parts. Also, you need to use a proper cylinder honing tool, the stones on it need to be as close to the same length of the cylinder wall as possible.
I guess I'm like allot of "Old Dudes" that watch. Yes I'm close(r) to 60 years old than I am to 50. I like Ike also have a soft part in my heart when it comes to old "B&S's". It's what we grew up with. It's what we used on just about every conceivable contraption we could come up with or actually build. To allot of us "Ol' Timers", a 5HP B&S is something akin to a Chevy 350 CID. Easily obtainable, fairly cheap, easy to work on and repair, there's all kinds of alterations you can do to one so the outcome is "something near" to what you wanted.
Yes Sir, you can go "new school" and get just about what you want right off the shelf, but (to me) there's nothing like spending a week-end out under the garage awning, getting grease under your nails, sweat in your eyes, skint knuckles, and the satisfaction of hearing "your creation" pop to life on the third or fourth pull.
Love and enjoy the videos Guys!!! Keep up the good work!!!
I'm 59, I'll be 60 on 9 Juan Juan....😁 I enjoy the heck out of working on everything...
I'm 68 and couldn't agree more. I still enjoy tinkering and building.
Longer skirt keeps the Piston from rocking in the cylinder. Allows for tighter clearances and higher rpms. Being able to run a tighter clearance means the extra ring is no longer a necessity. Also having the wrist pin closer to the rings creates a more even force on the Piston as it's moving up and down by applying the force closer to where the Piston comes in contact with the cylinder wall. Having it lower would push the skirt into the cylinder wall during combustion causing excess friction and loss of rotational momentum, ie loss of power.
I imagine a longer rod would also help with rev ability as well since it would make it a better rod/stroke length ratio
@@CallumTapper shorter rod, reduces (can't remember technical name) the flexibility of the rod and general stresses on the crank and wrist pin by reducing the mass as well.
To be fair a shorter rod also increases friction since the angle it has to take is much greater. Realistically this means that if you're running weak components a short rod will be better but under ideal conditions with better components a longer rod does perform much better at high rpm, just don't bannana your rod.
C.T. …………...in auto apps longer rod helps flatten out the torque curve, and helps with cylinder leverage filling @@CallumTapper
@@dannycalley7777 Also, the longer rod means slower acceleration/deceleration stresses on the whole reciprocating mass, giving it more revability and power.
Well wouldn’t add more oil would it? Wonder why
The reduced compression height of the piston (the wrist pin being up higher) allows for the longer rod which in turn reduces rod angularity improving the engines ability to not fly into a million pieces at higher rpms. This is also why most stroker motors don't spin up as fast as engines with shorter strokes. The longer stroke with the same length rod increases rod angularity. Essentially more rod angularity will reduce the engines ability to spin at high rpms but can net you some low end torque. Less rod angularity will lose you some low end torque, but allow the engine to spin to higher rpms allowing it to make more horse power.
Reduced compression.........means turbo it :P
It doesn’t have reduced compression. If anything it has the same or more.
Issac, it is nice to see that someone else watching actually understands engine performance!👍
Love high compression engines and old engines. I wanna do something like this too. I learn a lot from this:) even tho I'm a car mechanic :)
Also, the lack of one compression ring reduces the drag of the piston thus decreasing internal friction. The downside is the smoking. The lack of one compression ring allows more blowby into the crankcase which increases the pressure inside the engine. This is why the oil is being pumped past the oil ring. Perhaps a better crankcase venting system would relieve some of the pressure and reduce the smoking? Worth a try.
yupyup! less drag with 1 compression ring too BUT, put a little wear on the piston and cylinder, smokes like a pig!
My dad's old lawnmower had a Briggs and smoked like that. He used to say he was smoking the mosquitos out lol.
😂😂😂😂 Dad jokes
That’s great never would have a bug problem for sure
Actually he was
It's absolutely amazing to listen to someone who knows his Ka Ka. I built a go cart when I was
13, that was in 1953 Good for you guys..Looks like a blast. Brought back memories. Thanks
More Briggs! 👍Who cares about practicality, a Predator will never be even half as cool as an old school flathead :)
Hollaendaren same
Yes
Yes and no
10000000% agree. Something different about an old half wore flathead
I have a shelf full of them.
13:49 "that you'll never be able to find parts for..."
From my rather limited experience, the majority of parts from these old flatheads are still manufactured by _B&S._ Not only that, but these engines were produced in such large numbers that it's really easy to find a "spares engine" for sale on the local classifieds.
There is quite a lot of aftermarket support as well (ARC makes a ton of parts for 5hp Briggs engines), and UA-cam is awash with people doing all sorts of crazy stuff with old Briggs engines.
Just my opinion...
that's a race piston and rod. with possibly some light overbore. NOT stock.
I'm pretty sure John was referring to stock engines, or at least B&S in general.
Briggs 5 horse flat heads were the predator of there day. And parts are easy to find. The problem they do have is that the compression realise is a extra lobe on the cam shaft so when they run they loose compression and the only or the proper way to get around the problem is to grind down that extra lobe.
Briggs still produces the flat head and even produces and supports their racing line of engines so yeah you can get parts all day long.
Brodie Bennett your right I only work with flat head Briggs engines and parts for them are so easy to find just look for the engine model number go to Google and look up preformance parts for the engine code ....
I'd like to see a Predator last 40 years. Regardless, that thing sounds good!
As I understand it, the longer rod causes the piston to “dwell” at TDC longer as it changes directions in its travel. It causes cylinder pressure to get higher. So good for more power. Thing to look out for though is with higher pressure you have more heat. So engines with a longer rod could me more prone to knock on cheap gas. You should be fine with that optima fuel. Hope this helps.
I thoroughly enjoyed that, but a rat rod needs a rat engine, great video , thanks guys,
Fuck yeah mustie1 on c&c
needs an kohler flathead k582s, lmao
I agree, love your stuff.
Mustie1 Idk man, think they may need a few more shoehorns to fit a bb chevy into that lil thing lol.
My favourite channel commented how they love my other favourite channel, that made my day 👍🏼
I agree with ike. Ol briggs have a soft spot. And yes the parts are alot harder to come buy. But dang they perform. Worn out rings and a bad valve guide and still picked up 5mph and 2 sec.
I grew up doing exactly what you guys are doing. I love this channel, it reminds me of all the fun I used to have. You've rekindled the flame. I'm gathering old busted up tillers and snow blowers and once the summers here I'll be building a cart.
I'd like to see a vertical shaft engine cart build. I'd like to see how y'all setup the gearing.
Love the smoke! It's awesome and adds to the rattyness of the cart. The rat rod wagon brought me to your channel and has remained my favorite project.
Same!
I think that is what brought me to this channel
Longer rod = more torque
1 compression ring, should be a gas/pressure ring) = less friction
i grew up with briggs motors. forget the chineseium. i used to beat the sh!t out of them and they just kept going. soft spot here for old school.
Fully build Briggs, just to see. Y’all went this far might as well. I’m old school too. It be like a tribute to what started it all. Thanks guys
Sorry John I'm with Ike on the 5hp Briggs, it's the engine that started it all for us when we were younger. But agree with you on the predator engine if your just starting out with no mechanical knowledge etc. Build a dual Briggs rat rod with a wheel Barrow tub or something. Keep em coming guys!
Scott Govey Make it wheelie and call it the Wheelie-Barrow 😎
First off.. you guys are awesome. .. now about the smoking piston. I had a similar issue with my car pistons. They were aftermarket and the oil ring drain holes were not enough for my high reving engine. They only had 3 holes (6 total) on ech side of the piston. The stock had 5 holes (10 total) on each side. I drilled 4 more holes on the piston, being careful not to damage where the oil rings sit, this allowed the oil to drain back into the block easier. Since then my engine does not smoke, oil last longer and is less contaminated. Be careful not to hit the pin that holds the piston to the rod. You will have to drill at an angle. Good luck gentlemen.
Build another rat rod using a wheelbarrow tub using a old b&s 5HP.
I want to do that but with a k301 koler 12 horse engine.
DirtRiderX sauer sounds even more miserable to ride than the wagon
Hey if you wipeout in a wheelbarrow,atleast it will be a good dump.
I said the same thing b4 reading comments...
Great job, guys, and lots of fun. The nice thing about old engines like that is you can find them for free...or close to it...if you keep your eyes open and are willing to elbow grease it back to life like you all did. My favorite part of this build is the front-engine-rear-drive configuration you used. It's effective and unique...as karts go anyway.
The hone you used is for brake parts. The longer stone in a piston cylinder hone guide it holding it true to the bore, your cylinder is no longer straight. More than likely egg shaped. It will need a new sleeve. Valve guides are also in the same condition. The piston is a forged piston
Made for high rev's and compression. Able to withstand hotter burning fuels. You need a new block.
or just new valve guides? and a re re hone with a proper tool?
Roger yup, time for a block and see what it'll really do.
@@Hermiwalle
The bore is trash, passing that amount of oil the cylinder is gone
@@Hermiwalle
Briggs & Stratton does not use replaceable valve guides. The amount of Machining that it would take to install them, it's not worth the hassle.
Roger Marshall: oh ok. But I also imagine that a new 2 bearing block would be kinda rare no?
I think when you find an old flathead, it throws you right into tinkering and getting to know the mechanics of an engine (for beginners) and you can find something that runs for 50 bucks if need be. I love the front engine, live axle, drive shaft builds. I think another "rod" build with a 420cc, and maybe some sheet metal work could be very very cool
Between the smoke when they started it outside you can see flames
I am 53 & when I was a kid all we had was Briggs & sometimes the odd Tecumsay , had a 3 horse briggs on my choppered mini bike , & loved it . I love Briggs but a brand new predator works too .
Alright, jigs up. That's not Ike. Ike doesn't have a beard, but his twin brother does. You're not fooling me!
Yeah, he can't grow a beard so quick
Yall do know these videos are probably weeks old
@@2000stang5 Don't bring your logic here!
When he put a helmet on to drive and complained about the dirt Ike is always elbow deep in grease.
Illuminati confirmed
I love the old Briggs. Gotta give respect to them because from my childhood in the 80's it brought so much fun to us all and it was about the only performance era engines we had at the time. So me id love to see more of them being brought back to life and keeping the good time rolling like the old days
I'm with Ike on the Briggs. I won't claim to have any knowledge of go karts but at least on lawn mowers they are pretty reliable, and very fun to work on.
At 11:15 - Big 'ol Ike on that tiny kart flying down the road trailing a cloud of smoke - priceless!
I really wish you guys would pay more attention to proper ackerman. Almost all your builds have the ackerman backwards which is why they don't like turning. the inside tire should have more angle than the outside tire going through a corner.
differences in a standard, and racing piston, weight, alloy type, change in compression, ring design.strength these are the basics. The longer rod you have is to increase the time the piston dwells at TDC (helps with low and mid range power). The single ring lowers the drag on the pistons travel.
Ike, I have an affinity for Briggs and Stratton. In the late 70's I had a Clinton 2.5 Hp I rebuilt at age 9. Cool little motor made for gokarts.
Older Briggs are way better then today’s engines by a long shot there way more durable then anything built today I’m a Briggs fan by heart they have never let me down. One cold winter I went to start up my tractor that had an 1976 8hp briggs been sitting for 2 weeks or so and I kid you not I took two pulls and it fired right up them engines I have a lotta faith in them.
My friend and I race open wheel mod dirt track car we run alcohol and boy does that stuff ruin anything that's not steel we have a shut off at the tank and have to let the engine run its self out of fuel. Then we fill the vent tube right away with pump gas or else you will have to rebuild the carb and fuel pump from sitting even overnight or 2 days. Also, the skirting on racing pistons are typically taller for piston slap which can crack them eventually it keeps the piston more straight up and down in the bore since shit is not built like it used to be you pull apart a brand new bred and butter car's engine the skirting is super short for MPGS and weight savings on the rotating assembly. Diesel engines have much much taller piston skirting for higher compression after all they all knock naturally. If you ask a regular engine to push more power for extended periods of time you will find with a micrometer that the cylinder walls are egged chopped more than normal
mopartshemi I race a mod too!
Absolute correct Sir. You know it.
It does foul up the engine & rebuild more often because of aluminium , flush out with gas or it will eat it up .
Maybe with alcohol it might not smoke as bad uper cylinder lube ?
I love that y'all took it old school. I'm literally in the process of building a Briggs for my kids kart. Freaking awesome!
The older Briggs 5 hp flatheads will outlast the cheap Predator engines. They last forever!
Not really
Not the cheap Briggs that don't have an iron liner...they last 200 hrs tops. Also, flatheads run hot and go through valves like crazy. Older doesn't always equal better.
totally disagree with you flat heads are far better then newer motors if you can get 35 hp out of a 5 hp flat head I will take it all fucken day long!!!@@T..C..M
I have a 5 hp briggs from 96.
The only problems have stemmed from me not replacing gaskets. And an incorrect coil gap (found out when it stalled and had no spark)
Although it doesn't have a cast iron liner it still is amazing
@@mr.stonerUDX714 How do I get 35hp out of my 5hp?
I've gotten 3 Briggs and Stratton flathead engines for free, that's how easy they are to come by. One of them is on my custom homemade minibike, you can't go wrong with an old Briggs. Also, they are a little easier to fix than any new overhead valve engine and parts are still super easy to find, these engines are where I've learned my basic mechanic skills.
Thanks guys, it's so much more Rat Rod now.
l'm Ashley Smiley I live in Hazlehurst Georgia , being I'm 73 years old I guess I'm consider the old school guys. I raced carts for a few years and built my own engines and it sure would make you feel good to see it out front. the wiseco high compresion pistons, heavy duty rods,weber cams and a little carb work running on methanol. I enjoyed your show and looking foward to seeing it again
New overbore or sleeve/piston, valve guides and she'll be just fine... Predator Vs Briggs Raptor battle... How bout it?
Yep you're spot on sir.
I would love to see someone build another blockzilla briggs I haven't seen one of those in years
@@mudmowerregulators9559 blockzilla blocks are very expensive
The smoke balling up behind Ike’s back in his draft as he was screaming down the road is a knee slapper.
I’ve been watching and hope you guys bring the lay down go kart back when yo bought the three race karts
When you can get 15+ hp from a 5hp briggs I'm good we raced carts & built briggs with top straps on the motors to keep the heads on them they made massive hp with a few custom tweaks for internal piston weight & flywheel timing advancement etc !!
just imagine how much faster itll be when it has new rings and you can send it with all the compression
That looks like a 4.5 inch rod. If you measure from the center of the crank bearing and center of the wrist pin bearing you can tell. Then a matching piston compression height (0.590) I believe for the 4.5 long rod, and bore size. ARC racing has a page on there blog about calculations for all that. And you can get reamers and valve guide installer tools and Briggs valve guides on Dynocams and some other sites. And as for the racing pistons compared to the stock Briggs pistons, the racing ones are forged or billet aluminum to handle the higher rpm. The stock cast Briggs pistons won’t hold up long past 8,000 rpm. And with forged and billet pistons you run a bigger piston to cylinder wall clearance, because the metal is denser and will expand more in heat compared to a cast piston. It would be cool to see you guys rebuild this engine with a new piston and rings and show installing valve guides.
Perfect for summer...:) Three laps around the C&C Grand Prix.. No mosquitoes for days!!!!
I hate to say this Jon but that lil red flat top is what started all the fuss. Everyone was always trying to beat a Briggs and couldn’t. The old Honda’s made a good showing but it’s that name that made him strong!
i think a great name for this wagon would be ' Lil Smokey"
the longer skirt is to help the piston from wobbling to much and some times the rings width is smaller and the ring gap can be bigger or smaller.
happy to help and teach you about that.
BTW I am 15 hahah good luck guys.
More rat rod builds! The wagon is what brought me to your channel, would love to see another rat type build! Old school!!!
High compression pistons (racing, "High performance" pistons) give the engine a higher compression ratio by bringing the stroke length up with a taller piston, tall enough to increase compression ratio, but not too tall to start smashing into valves, or in your case with the flat head, the cylinder head. More compression, in turn makes more power. Hope I was of education, love the videos.
I absolutely love your videos, I have learned a metric shit ton of information/tips/ideas etc, please keep them coming. You guys should have a tv show. My only complaint? Watching you guys turn laps on these unsuspended rigs makes MY back hurt! I have literally found myself bracing for bumps and grimacing when you hit them ! Great stuff
Glen Piro Nice!!
Briggs & Stratton 206 crate engines are factory-sealed long blocks with ground cams and controlled piston pop-up (reducing compression variance). These budget-friendly mills feature a simplified IKF/WKA rule set designed to maintain a stock configuration, right down to the factory-shipped carburetor jets. Simply put: the 206 engines even the playing field so that drivers can focus on the important task at hand--winning the race!
Briggs & Stratton 206 crate engine features and specs:
* Primary use: Karting, Microstocks, Jr. Drag Racing
* Engines are assembled by hand in Milwaukee, WI using tooling and dies specifically designed for racing for unparalleled repeatability
* Reinforced, cast iron sleeved, dual ball bearing racing cylinder
* Single cast, custom aluminum alloy cylinder head with high-flow intake port, custom seat/guide material
* Squeeze cast, T-7 heat-treated aluminum rod with reinforced I-beam
* Carbon steel crankshaft with induction-hardened, micro-polished, crankpin-reinforced timing gear
* Cam ground, barrel-faced, eutectic alloy piston with 3-piece ring set with chrome faced top ring
* .255 max. lift ground cam with nitrited lobes and built-in mechanical compression release
* High-silicon, racing-engineered valve springs
* High-grade stainless steel dished valves with nitrited exhaust
* 3-piece, automotive-style keepers and reinforced rocker arm and lock ball
* PVL digital ignition with built-in 6,100 rpm rev limiter
* PVL steel hub, cast aluminum flywheel
* Briggs & Stratton tooled 22mm round slide, fully adjustable jet carburetor
* Custom graph oil composition head gasket
the longer rod reduces the angle at which it thrusts the crank pin, a reduction in side loading and fatigue life.
I liked the build man. Love the old flat heads. PLEASE do more. High performance brigs vs 212
My first engine was a Brigs and Stratton 5 hp it ran fine. You just can NOT let them sit
The Briggs flat head is a great engine. Modified Briggs and Stratton flatheads are used in almost all oval track go karts and you can make those engines rip. There’s also still a lots of brand new parts you can buy for it online
Looking at the 90 degree gearbox on this kart. Have you guys thought about using a lower end of an outboard boat motor? Not only will that provide a forward-reverse, but should also have a long input shaft instead of having to build one from several pieces.
There is a gear box just like that one that has forward and reverse
True, but they are way more expensive than a outboard bottom end that can easily be found at a scrap yard.
Racing pistons typically are higher compression, more sturdy in the cylinder as the skirt design makes them less likely to wobble side to side, and they often are made either by being forged or CNC'ed instead of being cast as well as they could be a special alloy that makes them stronger and able to handle higher combustion chamber temps.
Been waiting long time to see a flat head build love it
For many years Briggs was the primary engine in small power lawn equipment, and it still is a big brand in that business, although the new OHV engines are a different thing from the old flatheads. If I was doing a rat rod with a red wagon base like that I think I would extend it so you aren't cramped up so much, a bit more leg room would be nice. I had one of those wagons when I was a kid in the 50's.
Great show guys but yea do more rat rod shows really love the strange builds the wagon was awesome and i love briggs you gotta give them props they have been around for awhile love them
I agree with the look Issac is giving you John, you cant go wrong with a old school flathead briggs. You can beat the snot out of them and they just keep running plus they are extremely easy to work on.
There is a L compresion ring and that helps whit getting more compresion because the L ring is higher on the piston then a normal ring so you get more compresion
I have rebuilt numerous jet ski and outboard engines and I had good luck with Wysco piston sets!
1 less piston ring reduces the amount of friction between the ring and the bore so in theory should have slightly more power due to less drag.
That is what I was thinking
I figured 1 les ring+1/2of the rings seating means less drag more power
godda seal the power in tho its a tug o war between idea
That's been tested, thickness of ring. Friction verses sealing ability. A ring 1/8 inch wide will seal equal to a ring. 3/16 wide. On small engines the oil control ring is omitted on forged. pistons because due to heat the ring gap is wider, allowing oil to gather between the rings.
The Briggs & Stratton engine is like the Flat-Head Ford of go-cart engines. It has a cool factor the newer generic chicom clone engines lack. The Briggs is a perfect match for the Rat Rod Radio Flyer but I hope you can do a full repair of the motor with new rings and valves to see the full potential of this hopped up B&S.
Wanna see it fixed❤️❤️❤️ I'm and older guy so 5 horse brigs is in my heart for sure
Years ago, I built a 5hp Briggs like yours. Except it was built to the max! ,140 overbore with a Wiseco piston, a .300 stroker crank, full race cam, with a diaphram carb, and a stud and girdle kit to keep the engine together! @.140 overbore hte cylinder walls are pretty thin! this beast while it lasted was Dynoed @ 25hp !! had to reiforce the frame as well !!
This looks like a job for Lucas oil... 🛢
No no no, a job for Amsoil!
It's a 2 stroke Briggs lol
@@Garbasker no no no no a job for marvel mystery oil!!
How about Marvel Mystery Oil? A little in the crankcase, a little in the gas tank...
Maybe Lucas oil stabilizer or 50wt racing oil.
Hey guys, when youre doing a hone, slowest speed on drill and up and down as fast as you can go. The idea is to make crosshatching on the bore to retain the oil. As for the racing piston, idea is less friction and less reciprocating weight to gain the higher rpms. The small amount of compression lost by not ahing a second compression ring is more than made up for in the higher rpms. The skirt shape and design is to support this. Great video. I must say.. id love to see the ducati engine on the drag rail tho.. ... .. cheers, Levi
The rat rod wagon is my favorite build
God man look like u like it in the mouth sicko
The rat rod wagon was such a neat iconic build, I feel like it’s one of the OG builds too.
I'm liking the "it'll be fine" avatar.
Most oils today have detergent in it and if the motor inside was dirty from previous build up it will clean it and cause it to turn dark. Also once oil heats up especially on a air cooled engine it can burn it black quickly or if the rings are it can cause that also.
When I seen the thumbnail, I thought yea definitely ripping with that smoke trail.
Assuming the stroke is the same as stock, a longer rod on a shorter piston will provide less side loading on the cylinder wall and should (in theory) cause less friction and therefore less wear and quicker rev. It also provides a less abrupt change in direction when the engine rolls over TDC and the piston starts to travel down the bore which also helps with better revving. Best analogy I can give is when you go with a 6 inch rod on a 350 as opposed to a factory 5.7 inch rod. But again, you have to go with a different piston dimension otherwise you just made a stroker. As far as the single compression ring, I'm not sure the purpose of that. I prefer 2.
Ask project farm what’s the best product to clear up that smoke.
Morey's oil stabiliser or Lucas' works very well! Racing Pistons typically have less rings to decrease piston to barrel friction; It allows the engine to rev more freely and make it more responsive. The downside is that there is more pressure and heat the single compression ring has to handle as opposed to running 2 or 3 rings, so it will tend to wear out faster than a conventional piston and ring set
Guys , we would like to see you build a cart from scratch ! Race frame and a dirt bike engine !! Yeah !!! Or even a old two stroke triple ?? Yeah!!! how fast can you go ?? Big Balls needed for that !!
my first project was an 8 hp briggs and i had no problems it had broken bolts, broken govener, valve job needed , bought new carb and it runs like a dream
I love Briggs and Stratton you can fix a Briggs with some string and duck tape
I grew up with those old Briggs & old Tecumseh flat heads. They seem to make far more torque than the Chinee ohv motors of today. That ones already got the dual valve spring setup so the valves won’t constantly be floating once you hit 4500 rpm or so. As for the setup...the piston is lighter, longer rod likely means the builder is likely running a 3 1/2 crank for a shorter stroke coupled with a high lift, longer duration cam. Mic the cylinder to find out if and how much she’s overbored, get a set of rings if possible or a piston & rings...replace valve guides & seals. Add some timing with an offset flywheel key, dump some 112 in her & let her eat. Ya may also want to run a tighter clutch spring to get the r’s up before she locks.
I like the old school cool . Like the videos. Keep up the good work fella's.
The longer crank creates more throw due the extended stroke. This allows for a shorter ignition period and greater compression at high rpm. It allows the motor to pull greater throughout its entire powerband.
I disagree about not staying with a b & s engine.
Back in the 90's,my buddy had a 5 hp briggs on his go cart,he raced it into the ground,hitting jumps,doing donuts and climbing hills with both of us on it.
At the time the engine was old and it still ran like a clock.
The Tecumseh was also a good motor but you always had to mess with the carb on them for whatever reason.
As a matter of fact today he probably still has the go cart and I bet it would run.
The long rod setup reduces side loading of the cylinder walls as well as taking stress off the rod itself. It makes for a straighter line between the wrist pin and crank.
Love the build and I hope to meat you some day
What makes the racing piston better isn't the piston itself at all, but its the ability to put a longer rod in. The longer rod is more durable, creates less side loading of the piston in the cyl, also makes the duration of time the piston dwells at tdc longer to get more complete combustion. See what Smokey Yunick had to say in his books about rod length.
Y'all must be taking turns growing beards.
Just finished watching the rat rod build saga. Man it was good.
That cam looks like an old version of the 107SS from dynocams
Bern_The_Juice On the last video it was confirmed one
Nope Norris Really? They asked for some info on the cam in the video.
Bern_The_Juice Sorry, meant it was confirmed pretty much in the comments.
Nope Norris Oh, Alright then
Never stop a hone in the cylinder. Also move the hone up and down evenly in the bore and try to create a 45 degree cross hatch that will hold the oil in the cylinder and reduce ring wear. Remove the hone with it still spinning so you dont end up with your crosshatch horrizontal at the top of the bore
I was curious about the drive shaft system....ya gotta have balls sitting that close to something spinning that fast..😂😂😂
I've seen videos of guys getting sucked into machines. Shit is fucked up. The motor doesn't care, it will twist your leg into spaghetti, and maybe suck your torso in too if it doesn't sever your leg off first.
ha ha good stuff! The first engine anyone starting out should learn on is a 5HP Briggs bar none. You can find them in any old machine, simple design, easy to work on and understand how engines work. Just my 2 cents.
Diggin the beard Ike. 👍🏻
A longer rod changes the angle of the rod to the crank, its straighter, giving more leverage on the crank. Also gives a longer dwell time at the top and bottom of stroke. But also changes piston speed up and down the bore, this can be a bad thing with the standard camshaft duration and lift as it lessens the initial vacuum when the valve starts to lift which will affect the overall cylinder filling.
My experience building race Briggs motors I stayed away from longer rods and race pistons. Longer rods cos of the intake issues and pistons due to reliability issues.
Here's all you need, mill 0.020 thou off the head. Clean up the metal around the guide and the tricky one! 0.025 thou off the base circle of the cam, don't worry about the nitriding, if the followers are set right its a non issue. Polish and shot peen the stock rod and new bolts. Ran those suckers for 24hour races, won everything.
When we were racing gokarts, I used to swear that Briggs was developed by Chevrolet engineers...
"If it ain't smokin', it ain't runnin'."
...at least not running WELL, anyway.
Awsome vid...theese are the kinds of things that we miss out on when we get caught up and put the wholesome life aside. This is a great way to slow down...think of the 8mportant things in life and enjoy...at leat for the ones like me that love to hold a wrench...God bless every one and thanks for the vid.👍
A backrest would be a game changer. lol
I'd love to see that engine restored to it's former glory, at least performance-wise. I agree with John on all his points, but there's just a certain charm to sticking with something old-school and having fun with it.
As far as what makes a "performance" piston...in the case of something like this, it'll almost always be lighter, sometimes have one less compression ring (less friction), domed for higher compression, the skirt is usually taller, etc. You might have to re-sleeve that block, and if the valve guides aren't serviceable, then the block isn't worth saving. You'll likely be better off taking a good used block, sleeving it for that racing piston, and swapping over all your good parts. Also, you need to use a proper cylinder honing tool, the stones on it need to be as close to the same length of the cylinder wall as possible.