Starting Question


Jim H

When I assembled my first motorized bicycle, "Chinese happy time", I bought a wheel with a freewheel sprocket on the left and right. My intention was to use that sprocket instead of the 44 tooth which came with the kit. Got it all assembled, gassed up for it's maiden flight, took off and popped the clutch and no dice. Scratch head, try again, no dice then it hit me! The freewheel did what it does, freewheels. Installed the fixed 44 tooth sprocket, started first try. Yup! Felt pretty stupid that day...


:cool:Slicer, any luck on your pullstart hub? how are you going to secure it onto the jackshaft? are you going to pin it, key it or JB WELD it onto the shaft?

on my twin-engine project, i have at least 3" extra space on my jackshaft to install a pullstart hub. it would seem that all that's needed is a 2.5" long sleeve which could slip onto the shaft. or maybe a friction roller or a BMX foot peg.(the peg retails for $10/pair at SEARS, but needs to be redrilled and tapped for 5/8".)

is there a pullstart component specifically made for this application?

maybe not, but there are MANY pulleys that might work, on ebay. smallest is 2", and many more larger OD/5/8"ID/3/16"key. they will slip directly onto my jackshaft.

orrr, i just might have my jackshaft KNURLED 3" for the pullstart surface!

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Hello everyone I am in need of help. I got my bike running once. Since then I get the bike pedaling but when i let out the clutch it sounds like its running but when I try and give it gas it just has a low rumble but doesn't do much when gas is applied and then dies out. I've tried it with the choke on and off. Its getting fuel. I have checked the spark plug and it looks fine. Im using the stock spark plug that came with it. Also its getting fuel because it started nicely once and also the bowl on the bottom of the carburetor is getting fuel... Any suggestions would be much appreciated, thanks!

I got it running and rode it to work today. I cleaned out the air filter. It was very oily. I figured i must of mixed the gas to rich the first time. So I drained out the gas and measured the oil carefully this time. Its running great now. Thanks for all the advice.

Large Filipino

I talk about my bike alot in the forum I frequent often and this dude showed some pics. He don't remember where he got these pics but as you can see,it's a fixed rear sprocket set with a FREEWHEELING crank meaning the chain's always moving. Then check out where the jackshaft goes.
Look at what this solves. You can push start your happy time,which is what this bike seems likely to have,the drag seems minimal when you pedal it,you eliminated the tensioner and the spoke sprocket,and it HAS GEARS!!!


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