dunno bout the TT250 yet, (gimme a week or 2
but if its Anything like the Zong Sierra, you can bet Everything will b pretty darn heavy!(those things are built to b indestructaby strong), I'd go ahead and start looking for some good aluminum rims if lightening up is the way your heading. I think the Lotus race car guy, Chapman (and the Shelby too, for that matter) both were of the opinion that you don't need more power as much as you need less weight!! (PS: if you"re patient enough to lace up wheels check with Human Being for upgraded lighter and stronger spokes)! And, replacing that lead battery with a good LI one will save u a ton of weight! oh, and while at it, upgrade those tubes with lighter and stronger ones. I like the Michelin's but the KTM mechanics round trackside can tell who is the current favorite. I can vouch that EVERYTHING improves as the weight, (YOU TOO) and rotating mass, go down
keep us apprised