Thread: rear suspension
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Old 10-12-2015, 11:21 PM
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Tony01 Tony01 is offline
Motorized Bicycle Elite Member
Join Date: Nov 2012
Location: San Jose, CA
Posts: 613
Default Re: rear suspension

Oh damn.. I did not even think of the rubbing. My chain is real close like a 1/16" away from either stay so yea. But yea gotta jackshaft the pedal chain cause it wont clear with the stretch.

You'll figure it out. You're the scratchbuilder!!

I dont wanna hijack your thread but yeah the 2-speed works by having two chains for two gear ratios coming from the front jackshaft pulling the rear jackshaft. The front jackshaft is driven by the clutch on the engine with a 15t input pulley. The two sprockets are 11t on the front JS and they drive a 16t freewheel on the rear jackshaft on the right and a 10t clutchbell on the rear jackshaft on the left. So between the 10t and 16t that is the speed jump, 160%, since they are driven by the same size sprockets. So the rear jackshaft has the freewheel and the cent clutch shoes mounted solid. When you first start moving its just like any other bike, front engine clutch engages at 2200 and you start moving. When the rear jackshaft is spinning under 1900rpm (under 27mph, first gear) the 2nd gear centrifugal clutch is not engaged, so the 16t freewheel on the right is driving the bike. When the jackshaft reaches 1900rpm, the 2nd gear clutch engages, locking together the left side chain and the rear jackshaft (basically locking the front and rear jackshafts with some ratio) and since this ratio is a higher gear than the freewheel side, it now overrides the freewheel which starts spinning, and is the new ratio. First gear power transfer is engine to front JS, JS to JS on the right chain, then JS to wheel. top gear is all the chains on the left with the chain on the right freespinning.

My old setup with single speed was 8:1, 3.2" to 7" belt and then 12t to 44t. Was good but could not climb hills without a 15mph start. Now it will start on an incline. I kinda want to go back to a belt primary cause now Im getting oil slung on my leg every time I lube it. And these clutches have to be lubed like once an hour.

Yeah that orange crate build sure was pretty unique...
I don't always listen to Alice in Chains..... but when I do, SO DO THE NEIGHBORS
212cc 2-speed
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