1994 yamaha surge and wot problem

[Frank928]

I have twin 1994 yamaha txrs 250 engines. My right engine runs strong all the way up to 5800 rpms. My left engine tops out at 5200 and then starts surging down to 4500. It just started this year, last year they both ran solid to 5800. I am assuming fuel problem and I am leaning towards rebuilding carbs. Any other suggestions by any pro's would be appreciated.

 

[triumph190]

Re: 1994 yamaha surge and wot problem

It does sound like a fuel starvation issue. It could be anything from debris in gas tank, bad primer bulb, cloged fuel line, or as you suspect dirty carbs. If you have 2 tanks try switching tanks with motors and see if your problem stays with the same motor or goes to the other.

 

[triumph190]

Re: 1994 yamaha surge and wot problem

One more thing. I am guessing it is a 2-stroke, so if the engine is starving for fuel then it is starving for oil which will cause damage to your engine.

 

[Frank928]

Re: 1994 yamaha surge and wot problem

I did already try switching the tanks and the same problem. The other motor runs fine, thats why I was leaning towards the carbs. Would the fuel pumps cause the surge or the lower wot?

 

[triumph190]

Re: 1994 yamaha surge and wot problem

It could be the pump. Try pumping the bulb the next time your running it and begins to slow down. If it picks up and runs good then I would say it is the fuel pump. If not then I would lean toward rebuilding the carbs.