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bikerider

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I would love you see your small engine projects. I have a 2.5hp B&S horizontal shaft engine that I want to put to use but haven't found the right project yet. Google is showing lots of go-karts but my karting days have passed :lol: .
 
LDUBS said:
Mini Bike!
**************************************************************************************************

Or trike!

Roger
 
Had a mini bike back in the early 60's that looked kinda sorta like this one. Centrifugal clutch and used a chain & jack shaft. Rear brake was rudimentary. I think my brother and I used to have as much fun working on it as we did riding it. And, seems crazy now but no one even knew about helmets back then. Yikes!

Screen Shot 2019-07-24 at 8.05.36 PM.png
 
That mixer.... :lol: The mini bike looks fun. I think you would have to stick to smooth surfaces with no suspension. :mrgreen: :shock:
 
bikerider said:
That mixer.... :lol: The mini bike looks fun. I think you would have to stick to smooth surfaces with no suspension. :mrgreen: :shock:

Yep, these are not off road by any stretch. Of course when you are kids, anything is worth a try right. There was one time I had to spend some of my hard earned allowance getting the frame repaired at the local blacksmith shop. And, of course it wasn't street legal and I wasn't old enough for a license, so the local PD frequently made me walk it home. Good thing we lived in a small town.
 
When I was younger, small engines were my "thing". Then I took a job working on small engines, and here it is almost 30 years later, I could care less about them once I leave work.

But of many small engine projects was a home-made airboat. 1432 flatbottom, 3 seats. Rear seat, had a swivel screwed directly to the aluminum. On top of that was an adapter, mounted on that was a Kawasaki air cooled V-twin Horizontal shaft engine, home made tiller handle and a throttle made out of a brake lever and a crude cable setup. On the PTO end was a fan off of a Ford diesel pickup. Pushed the boat about 12mph at full throttle, ran in inches of water and on land and mud and across acres and acres of lily pads and up the ramp TO the truck (launch?) actually just wore the hull out and threw the whole project away.

Like I said that was just one of MANY little tinkering projects. Karts, bikes, mowers, you name it.

I grew up racing go-karts until 12 years old. All of them were briggs 5hp L-head engines, first ones were restricted with a plate between teh carb and block. Well during the summer when I was outta school I mowed yards with a push mower for some cash, to buy kart parts. Darn TORO (garbage) mower started acting up on me one morning, then quit. Looked in the tank and it was out. Yay. Poured fuel into it and started it up, it ran perfect. Bad part was, the "fuel" was methanol. Well since it ran fine, I ran it all the rest of that summer and from then on, I think about 4 years, all on methanol.

In about 2000 I was on delivery at work delivering a new mower to a guy. He had a Wizard riding mower that he gave me when I dropped his new one off, so I took the wizard home. 12.5hp L-head briggs vertical. 4 speed manual transmission. 36" cut. Well I changed the pulleys up from a 3" pulley on the crankshaft to an 8" pulley, then changed the 8" pulley that was on the transmission to a 3" pulley. Had to re-do the entire belt system which wasn't too hard. Darn thing went about 35mph in 4th gear, of course that was AFTER bypassing the governor. It was way too fast. Mower front axles are set up with zero caster so they are dangerous above about 10 mph, cant control them, so I removed the axle, removed it's pivot and re-welded it to give the front axle about 5 degrees of caster which helped dramatically. Now the transmission was a one-wheel-peel, worthless for anything but mowing grass. Removed it, welded up the differential gears, put it back together and had us a little drift mower. It, too ran on methanol. Why not? Easy enough...drill out the jet and adjust the idle mixture. It mowed grass too but only in 1st and 2nd gear and 2nd was a little too fast. My friend who later died gave me an idea...grab that little bitty turbo I had laying around the shop and make it work on that briggs. Yep did that too but we were only messing around with it, and that old briggs didn't have an oil pump so the turbo didn't get any lubricant. They last longer than you think with no oil. It made 10 psi, blow-through carb, for about 45 minutes until the shaft bearings seized. Shut it down, it cooled, and then it "freed" again, fired it back up and repeated several times, got the yard mowed but the compressor wheel was hitting the housing, sending metal through the engine, engine was really weak when we were done with it and we ended up throwing that mower away too. You'd have thought thatn 10psi turbocharged briggs would make about 15hp, but I couldn't tell much difference in power even after playing with the carburetor jetting. The block just won't flow enough air through the poor little intake port and valve, probably would've helped to "port it" and maybe go to large valves but why? That takes money...everything we'd done was dirt cheap and/or free and I wasn't about to put any more into it. Should've tried disabling the wastegate and see if it'd make any more boost & power but ran out of time and motivation.

Search on Youtube for a channel called warped perception if you like small engine stuff. Thats exactly the kinda stuff I used to do, of course I didn't have no high speed camera to play with, but I did everything the he does...glass heads, turbos, nitromethane, propane, liquid oxygen, gosh you name it I probably did it. Some of it was utterly dangerous.
 

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