I bought a used Fury, in what appears to be very good shape. Never raced as far as i can tell, never really bashed on, and, actually looks like it was barely used at all. The guy i bought it from though did do some upgrades, including swapping the brushed setup for a Castle Sidewinder brushless ESC and motor, which, by itself, isnt a bad upgrade, but, seems to have made it almost undriveable. What i mean is, at almost any throttle position, all it does is spin the tires and do constant donuts. I could start out with it barely moving, let it get what seems to be up to a decent speed, hit the throttle, and it goes off and still does donuts. I actually started out and let it get about 15 feet, and gradually kept increasing the throttle, got it up to about half throttle, which, by the time i was at half throttle, it had went at least 100 feet from the point i started it at, slammed the throttle, and it immediately went into donuts and burnouts. I did change the spur gear from the 17 tooth to a 20 tooth, but, it really didnt seem to make much difference, except that now it does only 2 instead of three donuts before just taking off in random directions, so, my questions are: Would changing the rear tires from the stock 2.2/3.0 SC tires he put on to a larger 2.8 monster truck style tire tame it at all, or would that just cause it to hook harder and then just do constant wheelies? Would a bigger spur gear, say even a 26 or 28 tooth have that much impact? If so, would that be negated by excessive heat that may be generated? I don't know if maybe he only ran it on NIMH batteries, but, i have a Gens Ace 2S 7.4V 5000MAH 50C battery i run it on, and, i don't plan on racing it, just running it around where i live, with everything from asphalt to grass to dirt to gravel, so, anything i do to it doesn't have to be ROAR approved. I just want it to be more controllable without having to break the bank to do it. I also bought a Racers EDGE Pro 2 SC truck from him as well, and that does the exact same thing the Fury does, so, im looking to actually make the same recommended changes to both trucks to get them more controllable.