Two Stroke Jack Shaft


Active Member
Feb 25, 2020
If I install a Jack Shaft Kit on my China Girl 2 stroke is starting the engine going to be a problem?
I have had this kit laying around for a long time and can't decide if I want to install it to use the right side chain and derailleur system for transmitting engine power to the back wheel. What if the chain breaks?
I am looking for some advice from someone with experience in this area.

Captain Rainmaker

New Member
Mar 22, 2020
I have a jackshaft kit on my bike. Starting is really not that big of an issue. I'm assuming you're talking about the Sick Bike Parts kit, and I know in the instructions it says you should stand up and kick down as hard as you can to get it going. I've never had to do this; I just pedal a bit harder than normal and it fires right up.

Make sure you use high quality chain, and carry some spare links and a chain breaker.

Sidewinder Jerry

Well-Known Member
Dec 19, 2011
Rockwood, TN
Use your lowest gear; it'll be the easiest one to get the bike started. Often the complaint with shift kits is the gear ratios are too close together and that the cross chaining puts a lot of wear on the chain and gears. Here's a tread I did to solve that problem.

I highly recommend getting a tachometer. Then you'll know precisely when you need to shift. They sell very affordable tachometer/hour counter on eBay. This is much more accurate then the sound/ear method.
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