This is the 2010 Husqvarna TC250 the way the MXA test crew raced it. As a rule, we don’t go for exotic or expensive mods, but if push comes to shove, we will seek competent help (no matter how much it costs). Use MXA‘s mods as a guide.
Steering head bearings. The bearings seized after six months. They were so galled that it was hard to turn the bars. Buy a spare set of steering head bearings.
Engine. Ty Davis was our source for the majority of Husqvarna TC250 help. Ty is sponsored by Husky, and his Zip-Ty Racing shop knows more about the bikes than anyone. We had Zip-Ty Racing blueprint the cylinder head to increase flame path, straighten out the intake tract and modify the seat angle ($675.00). We also had Ty true the crank ($150.00).
Kick starter. We kicked our TC250 so many times trying to get it to start that we bent the stock kick starter. New jetting finally helped the bike start, but we still needed a stronger kick starter. Zip Ty Racing makes a stronger one at www.ziptyracing.com.
Jetting. We swapped out the stock OBDVR needle for an OBENR needle. We ran the clip in the fourth slot from the top. We found it best to go leaner on the main (a 180 instead of the stock 190) and richer on the pilot jet (40 instead of 38). Rather than try to fiddle with a leak jet, we installed a Boyesen QuickShot with adjustable leak jet (and we used this in conjunction with a stiffer accelerator pump spring). The float height was set at 8mm, while we set the fuel screw at 2-1/3 turns out. Whenever we had a question about our jetting, we called Zip Ty Racing at (760) 244-7028. They offer a complete carb mod for $275.00.
Shock. We have limited experience with the Sachs shock that comes stock on the TC250. We ran the stock 5.4 shock spring with the compression and rebound on 16 clicks out. The high-speed compression was best at 11 clicks out.
Cams. We left the cams standard for good reason?there are no aftermarket cams available.
Forks. The 2010 Husqvarna TC250 comes with Kayaba forks. We’d guesstimate that these are 2007 Yamaha YZ250F units. We immediately upped the spring rate from 0.42 kg/mm to 0.45, but in the end we had the forks revalved by Pro Circuit to 2007 Yamaha specs.
Clutch. We had horrible clutch experiences in the beginning of our test period. In the middle of a moto, the TC250 clutch would go away. Then, later in the moto, it would return. This was not good. We suspected a leaking seal in the hydraulic system and put on a completely new lever and master cylinder. We never had the problem again. We did have Zip Ty Racing modify our clutch basket for better oiling on the bronze bushing.