Gearing/tire size

[Abennett]

Looks like my sons local racing group is changing tracks next year, (circle track) the track for next year is 3 to 4 times as big with slight banking, the straight always are 600 to 800ft long with wide turns, I'm gonna need to change the gearing for more top end, I'm planning to buying him new wheels and tires anyway would I be better to buy taller rear tires or keep the tire size and do the change in the sprockets? If yes on tires what size would you guy choose? He has a mildly built drr70, thank for any input Andy

[hotquads1]

Andy, your shorter tires make the quad sit lower which is more stable at high speed(lower center of gravity), so sprocket may be better choice, unless you need more ground clearance.

[Abennett]

Mark what do you recommend front rear or both sprockets? Tooth numbers? Thanks Andy

[#404's Dad]

The 12 inch Hoosiers always worked good for us regardless of the track size, Not the super wide ones that look like jelly beans at high speed though, Gearing will be determined by Track Size, Trans Ratio and Power.

My favorite Gearing was 23/27 on a 70 with an aftermarket High Speed Trans, this was all back in 08 ans 09 and it worked but I'm sure there are better ways to skin the cat now days.

All our TT stuff is for sale and I have tons of gears, no junk either, Email me if interested at Info@FiercePowersports.com

[fomospede]

that trans selection would be ideal

[hotquads1]

404's Dad has a ton of experience with these set-ups so I would try his recommendation, but I am thinking your mild 70cc is a few HP less than his national engine so I would be suprised if you pull that much sprocket, trial and error is priceless.
Marc