i have a 2002 eton 90 thunder, d&d pipe, ported & polished , 50thou. off cylinder head , some new clutch work, rejetted & runs very very nice my question is this the tires that are on it are 19 7 8's do you think I can run 20 7 8's with out hurting bottom end pull or do you think the inch is too much just stick to stock size we do lots of trail riding no racing

 

I say go for the 20 inch tire. If it does hinder your performance the you can drop a tooth on the front sprocket.

 

I would love to drop a tooth if I could find sprokets for this eton other then stock

 

One thing you have to watch is the wieght of the tires.Some of the adult sized quad tires are very heavy compared to the stock mini tires(hurting performance).Also watch that the chain doesn't come into contact with the swingarm when going smaller on the front sprocket,might be better to go bigger on the rear.