Right hi thumper talk! my 07 450 is slightly tuned running 57.3bhp and has been fine all year racing mx.. until it busted the out put shaft.. second gear was also worn (or damaged-hardening had started coming off) replaced these parts and all bearings in case!!! bike was then better than before..... until last weekend, last race of the season.. the gear opposit second gear (think its called second gear idler??) broke and destroyed second gear:banghead: now i have lost all faith in the gear box... although all the other gears look good no damage appart from 1 small chip about 1mm but probably smaller i love my yam and really cant afford to get a new bike but also cant afford to replace every part in box as this totals to around £800 any sudgestions on how durable these boxes are and have i just had bad luck?? thanks!!