I have a taotao 110 four wheeler that has a loose chain how shouldi tighten it and i want to put a sprocket with less teeth on the front but it wont come off or tighten so can i get a different rear sprocket. And also some of the plastic tabs snapped that holds the plastic feet holder things up good ideas on how to fix.

 

your quad should have a chain tensioner that looks like this:



if not, you may have to roll the axle like you do for a polaris TBlzr.
don't know about your other items, i'm not familiar with your quad.

 

You should have 2 chain adjusters on the rear axle/swingarm.
These need to be removed to make equal adjustments and keep the rear axle straight.
They should also not be over tightened as they will strip the threads and then need to be replaced.

It is far easier to loosen the large bolts that mount the axle to the swing arm, both the 2 top and the 2 bottom bolts. The lower bolts should go through a slot on the swingarm.
Then remove the adjusters, make equal adjustments, and then reassemble. Tighten the larger bolts very tightly and snug the adjusters. It is important that the adjuster have a nut before and after the swingarm. Meaning when you slide the adjuster through the rear of the axle bracket have a nut on each side of the bracket metal, otherwise you will come out of adjustment.

The chain should have a half inch of travel up and down while the child is seated on the quad. When the quad rear spring is compressed the chain will tighten as the swingarm pivots. You do NOT want a tight chain as it will rob power from the motor due to friction and tension.

The rear sprocket may require you to remove on side of an axle, I would need to see your quad. Then purchase a rear sprocket with the appropriate number of teeth that you want and for the right size chain. Their should be 4 bolts holding on the sprocket. The front sprocket may be part of an output shaft on an internal gear box and may not be able to be changed. Some are some are not.

The plastic foot holder is probably the rear heel gaurds behind the foot pegs. You should be able to replace those.
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