topend

Hi Guys I have now done about 100 trouble free hrs on my '10 FS570 motor, no racing...love this bike! So far I have done all the servicing as per manual and at 90 hrs it says to replace the piston, camshaft bearings, etc. What is the experience here on the forum, is this really necessary...

I have old Husaberg FC501 1991. Engine start easy and run nicely but middle and top-end power is lost. Low rev rpm engine is strong but that's it. Fuel is new, and carb is std setting. If I increase speed and close throttle I can hear some back fire. My opinion is fire timing is late, but how I...