What will this do? Will it help? Thanks

 

it keeps your intake and exhaust valve clearances correct,,,,as they will go out of adjustment

if they are way out,,,,you will notice huge power gains and smooth (one touch) starting

it is basic maintenance on a 4 stroke and should be checked periodically

 

NE body and also what would be a good rim and tires for about 160 bucks?

 

Depends where you are riding.

 

Hard pack dirt and grass and some loose dirt