Re: yamaha 150 txr 2stroke
Is it possible that the crank sensor may be changing the timming to reduce RPM? Or thermo switch doing the same ? With motor at 4000 RPM increase rpm only makes motor start to surge instantly!!! Primer bulb is still tight when pumped at this rpm. Filter at motor new,10 micron 1quart fuel /water saperator new. At one point while running at 4300 rpm surging, motor picked up to 5000 rpm for 20 seconds and decreased back to 4300rpm and surged.I stopped motor!! started up agin it would not turn over 2500rpm and would bog down if I increased throttle. After 2 mins. it came up on plane and ran at 4000rpm back to launch ramp. What next Yamaha mech.has cleaned carbs, 3 months ago, well He said he did I marked everything nut and bolt on motor to see if he removed any item for repair!!!!!!!! Who do you trust??