Hello Scorpa people! 
Just bought my first trials bike, having owned various air cooled trials bikes years ago - which were only used for playing on.  New bike 05 SY250.  Been regularly used for 3 years. I was wondering : 
How often do you change the silencer - and other parts of the exhaust ? 
Ditto - piston, main bearings, etc ? 
Do you recommend a mod into the float bowl brass nut that creates an easy way of draining the flaot bowl ? - because my bike has one ? ! 
The engine is a tad noisy and reminds me of a TY250 that I once owned - I always reckon it sounded like main bearings - but that could just have been paranoia !  I was spectating at a trial on Sunday and it struck me how quiet a new Gas Gas was that I happened to find myself standing next to. 
All advice really appreciated ! 
Harvey