Need help with 90

[riding4fun]

The kids and I went for a ride today. Everything ran well for approximately 20 minutes. Then the 90 started stalling. It would start back up and bog down and then stall under acceleration. I adjusted the mixture screw both ways, no change. I pulled the spark plug and it seemed to have some oil on it.
I changed it and it ran for about 30 seconds then it died again. I towed it home and looked underneath. There seems to be oil coming from the exhaust flange. What could this problem be?

The mixture screw is 1/2 turn out per my dealers instructions.

Any help is appreciated

Darrell

[drr wizard]

sounds like a vacuum being created , starving for fuel ,check your vent hose and cap for proper breathing. a restriction here will cuase bike to stall bit after sitting a few moments preasure will equalize and it will run a few more seconds untilit starves again. A simple kink in air vent hose will cause this . easy way to check is run bike without capand see if problem still occurs. good luck

[riding4fun]

drr wizard,

Thanks for the reply. I was talking with somebody else and he also said it sounds like its starving for fuel. I will take the carb off tonight, clean it out and check what you said.

Darrell

[drr wizard]

before pulling carb you might want to disconnect fuel line at carb and open petcock and check to see if you have a good flow of gas to supply the carb, if not a good flow... no need to suspect carb. the reason I bring this up is you stated you had been riding for 20 minutes , running well I suppose , carb should not require any changes . Since your atv is equipped with a fuel filter the last place I would suspect debris is in carb, unless you have recently opened carb. 1/2 turn on air screw should be very close, you also might want to verify there are no restrictions in air flow to carb ...air filter etc. Check for air leaks around carb and intake ( vacuum leak) this can also cause a lean condition that could show symptoms you are describing. good luck

[riding4fun]

drr wizard,

Thanks for the help. The gas flow to the carb was fine. So I took it off and cleaned it completely. It is running good again.

There was some dirt build up inside a couple of the holes. All better now. This is the first time I have ever taken a carb off. It actually fills good to do something yourself.

Darrell

[bulldogfallon]

Get an outerwears for the air filter housing

[miniquad]

Put a uni air filter on it less restrictive and better dirt protection than the stock filter.

[riding4fun]

I did put the UNI and outerwear on, but the damage was done. But it's all better now.

Do any of you live in the Nevada area? I seem to think this thing may be jetted too high. It is about 2000 elevation here and dry.

[AFROracing]

do a plug check...


install a new spark plug, run it wide open and shut it down..

pull the plug, if it's white jet bigger!

[riding4fun]

I re-jetted it with a 100 today. Boy this thing takes off hard now but seems to lack mid-range.

What would be my next step to get the mid-range?

I only rode it for a few minutes and checked the plug it definately wasn't white . Good thing right?

Thanks again,

Darrell