yamaha wrf 250 problem

[gerry b]

anyone can help with this please, my son has a Yamaha WRF 250 endure 4 stroke single carb single cylinder year 2004, it starts & goes like a rocket, when it gets hot say after 5 mins its slow to return to idle, stays around the same rpm as if the choke was out, when you get it to idle it revs up by itself, problem seems to be drawing air, he swapped the carb, the throttle position sensor and the carburetor rubber joint with another bike but same problem, any advise please Gerry b.

 

[gerry b]

should have spelt *enduro*

 

[JohnnyBoxer]

should have spelt *enduro*

and put it in the right section

The people in here have no idea about bikes manufactured after 1996

 

[gerry b]

thats a great help

 

[degsey]

anyone can help with this please, my son has a Yamaha WRF 250 endure 4 stroke single carb single cylinder year 2004, it starts & goes like a rocket, when it gets hot say after 5 mins its slow to return to idle, stays around the same rpm as if the choke was out, when you get it to idle it revs up by itself, problem seems to be drawing air, he swapped the carb, the throttle position sensor and the carburetor rubber joint with another bike but same problem, any advise please Gerry b.

I guess its pre injection

Start the bike and spray some WD40 around the carb rubbers to see if the bike revs itself up. If it does you have a leak on one of the inlet rubbers.

with the bike off make sure the throttle is returning qiuckly and not to slow or getting stuck as its shutting

Turn the bars left and right full lock to see if the bike revs its self up

Turn the engine idle speed down a little and I mean a little Milimeters at a time.Turn rev it....Turn rev it. see how that goes

 

[Rob Farmer]

What's a Yamaha?