91 Yamaha 200 V6 surging when I hit 3600RPM

[Road Racer]

It is a two stroke. When I hit 3600 RPM the motor surges from 3600 to 4000
RPM every five or ten seconds. What could cause that?

 

[JUSTINTIME]

Re: 91 Yamaha 200 V6 surging when I hit 3600RPM

fuel bulb staying hard?

 

[rodbolt]

Re: 91 Yamaha 200 V6 surging when I hit 3600RPM

bad fuel pumps,leaking fuel lines, restricted fuel lines. lots of things will cause a surge.