Engine problems



hey im new hear but i have a 2000 yamaha blaster with full fmf exhaust boyensen reeds and it runs good but when i hit high speeds it boggs out then when i slow down it starts running again... please help me
do you have the tors system removed if u do its prolly the reeds diss connect the t.o.r.s the wires from the throttle n off the carb diss connect it if it still runs crappy it could be the reeds
I had a dirtbike do this at full throttle. It would also foul the plug. Your jetting could be off a little. Or your piston needs some new rings. Remember in my case I was fouling plugs too.
Check your compression should hold around 125 psi.

if compression is ok then this is a jetting issue.