things Ive done with great results
hey there folks :) Im jak stoll
Jak Stoll Performance
Im running the 70cc HT on a schwinn frame with worksman wheels Ill try to get pics up of it
I have a big 14 inch cut off wheel which I used the side of to shave off about .8mm or more from the head,
pulled out the lower jug gasket & used RTV
I was able to port out the inside of an extra stock carb I bought so the opening is like a stack inside of the filter & maybe got one mm or more in diameter
I went down with the floor & get a decent idle with the idle screw not touching the slide, air moves under, the mods on the carb leaned it out quite a bit so I got more RPM & when I dropped the needle back down got more torque
I think the compression made the biggest difference in pulling hills as well as top speed I also worked on the intake a bit
Im going to try the skirt tomarrow :)
I love my old bike
I used to downhill in the late 70s before there were mountain bikes so this is like downhilling all the time with the 36 tooth rear sprocket I can get up to the high 30s low 40s on flat with neutral wind & have been clocked at 40MPH not wound all the way out :)
I use a car fog light & a small truck marker in the back running A123 batteries to power them & just recharge them
anyway it will be nice to learn & contribute here, I plan on using a worksman frame & isolate the engine with rubber mounts in the future too
take care
here are a couple of pics...


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Active Member
Jan 27, 2008
Ptown, Texas
Welcome to the forum. Looks like you been busy improving your motorized bicycle. We're glad you joined us.....................
hmmm :) that would be 0B people :)
I do tune in binary :)
I tought myself believe it or not :)
I use a graphing hex editor I have to correct checksums & all that :) '

I dont know allot about 2 strokes but the fueling & moving more air is universal
I look forward to learning here
I love my bike & have put a fair few miles on it & have probably saved several hundred dollars or more on fuel
thanks for the warm welcome
on the carb I got it dialed in beter today, lowering the top of the jet holder to the floor of the venturi willlean it so I was able to then dial it in with the pin & it is way better
porting the carb is a viable solution if done well
take care
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hey there guys :)
I lowered the intake port floor a bit with my engine & WOW'
its got a real power band
I did loose a bit way way low in the RPMs but what I gained in the mid range is well worth it
I would strongly advise this method
someone here sugjested it & or modding the piston to change mechanical timing
it is a great move
I cant wait to get a expansion chamber on there
take care