Havasu Dave's - "Mini Bike" - (Just For Fun)

The advantage of working on mini bikes is the turnover time. A car project takes years for most people. A big bike can easily take 1-2 years or more. With a mini bike you can start with a rusty hulk and have a showroom ready finished product in under 6 months. And based on what I see, all your brain occupation has paid off nicely. I learn a lot just following your projects and I'm pretty sure you'll find lots more out there who are glad you put so much thought into what you do! Thanks!
 
No dummy, the piston was not backwards again, the new rod bolts were three threads longer and hitting the bore skirt. (Bottom of bore)

I don't know what happened to my last post, but here is the intake section with the new hole drilled in the intake/stuffer to match the pulse pressure hole in the reed cage, which matches the hole in the carb, which is what makes the carburetor pump fuel.

[MENTION=31879]CarPlayLB[/MENTION] gaskets and reeds.

 
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Awesome build. I love the fact that you are building with common basic hand tools found in most garages.
I saw you guys talking about fuel:eek:il ratios and was wondering about the need for that much oil. I run my built to the ceiling scoot on 40:1 and have been for years. No bearing slop, no scorched bore and no high heat. Is it a standard high oil ratio thing with the vintage type smokers?
From what I can see of that exhaust, is it just a horn? Or is it an internal chamber design?
Can't wait to see the finished product.
Oh, if it looks like I am trying to pick apart our buid, or second guess the collective wisdom of this awesome site, I am sorry. That is not my intention. I am here to learn everything I can about these engines and hopefully find an old man be for sale near me here in KY.
 
Finishing up with the "third" mock up of the machine for engine run and chassis testing. Waiting on a PTO seal, and hardware for the tank mount. Tank sits on rubber grommets. Mount hardware will be countersunk below the frame. I'm still working on an intake filter solution. Looking forward to where I can get to body work.







 
First start up after modifications to intake, and wow. Easy to adjust, very quick rev-up. I need to do a few things, and then I'll test ride it again.
I'll bet that baby revs! A racing gokart engine on a minibike can be very exciting. I look forward to your video. I had a Mac6 on a minibike when I was a kid and it felt really snappy, and tended to load up if not kept rev'd. Speaking of two-strokes, I wonder how Jason is doing with his Jacobson powered Low 'n Slow.
 
I just got back from a test ride, where I attempted to vibrate the seat mount up my arse. It revs up much quicker, and I estimate has about 1/3 more power than it did before the intake modifications. One thing that I am tickled with, (besides vibrating seat mount) is the ease of carburetor adjustment, and how predictable the throttle and acceleration is.

I'm very happy. The ratio I will stick with is a final 1:5.5. It wants a bit lower than that, but carries the power okay. (Tires are 12" diameter) It will idle all day if I let it. No loading. Tilly clone is fuel pump down, and cover snug, but it will drip fuel until I shut off the tank. I can deal with that.

I wouldn't expect a lot more from this tiny engine on gas. (Using Burris at 20:1) Time for celebratory adult beverages, while sucking down cigarettes and blue castor oil smoke.
 
I just got back from a test ride, where I attempted to vibrate the seat mount up my arse. It revs up much quicker, and I estimate has about 1/3 more power than it did before the intake modifications. One thing that I am tickled with, (besides vibrating seat mount) is the ease of carburetor adjustment, and how predictable the throttle and acceleration is.

I'm very happy. The ratio I will stick with is a final 1:5.5. It wants a bit lower than that, but carries the power okay. (Tires are 12" diameter) It will idle all day if I let it. No loading. Tilly clone is fuel pump down, and cover snug, but it will drip fuel until I shut off the tank. I can deal with that.

I wouldn't expect a lot more from this tiny engine on gas. (Using Burris at 20:1) Time for celebratory adult beverages, while sucking down cigarettes and blue castor oil smoke.
Congrats on getting her back alive! Should be a cool, if not blue hazed, video! :laugh:
 
I just got back from a test ride, where I attempted to vibrate the seat mount up my arse. It revs up much quicker, and I estimate has about 1/3 more power than it did before the intake modifications. One thing that I am tickled with, (besides vibrating seat mount) is the ease of carburetor adjustment, and how predictable the throttle and acceleration is.

I'm very happy. The ratio I will stick with is a final 1:5.5. It wants a bit lower than that, but carries the power okay. (Tires are 12" diameter) It will idle all day if I let it. No loading. Tilly clone is fuel pump down, and cover snug, but it will drip fuel until I shut off the tank. I can deal with that.

I wouldn't expect a lot more from this tiny engine on gas. (Using Burris at 20:1) Time for celebratory adult beverages, while sucking down cigarettes and blue castor oil smoke.
That's great, getting that Westbend to run nice like that.
 
Congrats on getting her back alive! Should be a cool, if not blue hazed, video! :laugh:
If I can make the cut off date Pete, I'll do a video. If not, I am more than fine with that. When I rode to the top of the street and turned around, there was indeed a fine, blue haze.

That's great, getting that Westbend to run nice like that.
Thanks Aston jag, I was fortunate enough to have some expert help on it from some of the vintage karting guys, as well as CarPlayLB who not only had more knowledge on this than I did, was quick to send needed parts, gaskets, and very nice reeds.

My exp. with 2 strokes has always been plenty of vibes. But that is part of their character. :) Looking forward to the ride video.
Lots of vibration for sure, especially in the aluminum hand grips. It could use a second gear. It winds out pretty quickly, and then I have to hold it back. I ought to buy stock in Loc tite.
 
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