Surging / Jumpiness @4-5000RPM

[VT_BluYamaha54]

If I am riding a narrow trail below 20mph, I have an AWFUL time with my Warrior "surging" between 4-5K RPM. It is like it has a lean spot and keeps jumping to a higher RPM w/o corresponding throttle movement. Above and below that range it is fine. It has done this since new and is completely stock.
Since that is the approx range where the carbs go from pilot to main is there any adjustment? Is is possible it is the clutching? A friend suggested this but I think it is the engine/carbs. What I should probably do is run it on the stand to see what it does.

Thanks in advance for your experienced input!!

 

[rightarm]

VT that's low speed stuff that would fall under you needle or neddle jet your main's really don't kick in until 3/4 throttle to full throttle,I would do a carb sync first then go from there.More than likely the carb's are out of wack do the sync on the carb's and if the problem still exsit's then check the needle jet make sure it's not plugged.

 

[VT_BluYamaha54]

Thanks Rightarm but I am not that familiar with these CV carbs yet. How can I identify the needle jet?

VT_BluYamaha

 

[rightarm]

VT sorry about the late responce the needle jet is located in the float bowl,below the main jet it is hidden underneath the float bowl arm.It's attached too the needle under that reside's your needle jet.

 

[VT_BluYamaha54]

VT sorry about the late responce the needle jet is located in the float bowl,below the main jet it is hidden underneath the float bowl arm.It's attached too the needle under that reside's your needle jet.

Could that be the same as what I call the needle valve? The needle on the float goes into it and regulates fuel flow into the bowl?

 

[rightarm]

carbs

VT that' a 10-4 other wise know as the needle and seat.

 

[black john]

surgeing

check your pilot jets they plug with varnish realy fast as they are so small thats the long thin one in side of the float bowl. mine can pluged from new . 8)

 

[rxrider]

My sled started to act like yours. Checked the pilots and everyone of them was plugged. After cleaning sled ran just fine.