wont run right

I have a 98 yz400f was out riding started cutting out then ran really rough. Cleaned the carb found a bad acc pump dyaphram put in a new one. now bike will start right up and idle all day as soon as i try to give it gas it dies.:) should I still be looking at the carb as the problem or think it could be the tps or any thing else elctical? or valves?

Unplug the tps and see if that helps,if it doesn't help try other stuff.Process of elimination and persistance usually turns up the issue.

Still a carb issue. give it another good cleaning. maybe a pilot circut issue. check and reset your screw. maybe replace the pilot jet as they can become varnished over time.

Cant belive I didnt check sooner all this time it was the gas. Flushed my tank put different gas and runs like a top again:banana:

Cant belive I didnt check sooner all this time it was the gas. Flushed my tank put different gas and runs like a top again:banana:

Ive done that before :)

Ive done that before :)

Main reason I didnt change out the gas is the same race can it came out of is what the kids have been running in there go kart problem free.

Main reason I didnt change out the gas is the same race can it came out of is what the kids have been running in there go kart problem free.

I'd imagine that tiny little piston in that tiny little combustion chamber takes a lot less inertia to turn an engine than it takes our thumpers from hell.We need all the gas we can get.I have noticed after two weeks with the same gas in my bike,it doesn't like it.I guess I'd feel the same if someone tried to shove three week or more old nasty food in my mouth.EEEEWWWW!!!:)

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