Uneven Acceleration

[GearNut]

Improper sprocket alignment is the biggest cause of chains falling off. The next cause is a chain that is adjusted too loose. There should be 1/2 inch of free play on the slack side of the chain.
The factory chains are also known to be trash right out of the box.
It should also be noted that some of the sprockets, both engine and rear wheel, come from the factory with burrs on the teeth that need to be smoothed out. Also on some of the the engine sprockets the valleys between the teeth are machined too deep and the tips of the teeth need to be very carefully filed just a little bit shorter to fix this problem.
This must be carefully looked at though. Do not assume any of the problems are actually there and merrily file away at the sprockets. Look closely at how the chain wraps around the teeth and see if it is getting hung up before modifying the sprockets.

 

[slimshady]

Improper sprocket alignment is the biggest cause of chains falling off. The next cause is a chain that is adjusted too loose. There should be 1/2 inch of free play on the slack side of the chain.
The factory chains are also known to be trash right out of the box.
It should also be noted that some of the sprockets, both engine and rear wheel, come from the factory with burrs on the teeth that need to be smoothed out. Also on some of the the engine sprockets the valleys between the teeth are machined too deep and the tips of the teeth need to be very carefully filed just a little bit shorter to fix this problem.
This must be carefully looked at though. Do not assume any of the problems are actually there and merrily file away at the sprockets. Look closely at how the chain wraps around the teeth and see if it is getting hung up before modifying the sprockets.

Where do I buy better quality chains?

 

[GearNut]

I got mine at a local independent motorcycle shop. A Tsubaki 415 standard non o-ring for $20.00.
Some folks here get theirs from the vendors that advertise on this site.
Pirate cycles comes to mind. They sell a decent quality chain at a fair price. Other folks get chains from Tractor Supply.

 

[handyandy91]

Yep, my chain that came with my 66 cc starfire would not fit my 40 tooth sprocet.
The first 10 or so links went around fine then boink, no more fit^@#$!!!
Put on a Tractor Suply #41 chain, Fit awsome!!!!!

 

[slimshady]

thanks guys. umm i have another question, my back wheel is wobbly when it rotates. by this i mean that when i accelerate, it wobbles side to side. i didnt even notice this until my friend told me how screwed up it looks when he saw me ride it. so im curious... how do i fix this? is the wheel screwed up? or can i do something to fix it? thanks.

 

[GearNut]

You will have to hold the rear wheel off the ground and spin it. Look to see if the rim needs truing up, the tire is not seated properly on the rim, or the wheel bearings are set too loose.
Truing a rim on a wheel assembly is not hard if you have the patience to do it.
Re-fitting a tire on a rim is easy.
Properly setting the wheel bearing pre-load is also easy, it just usually takes a few tries if you are not familiar with doing it.