surging Idle problem

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shwinny
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surging Idle problem

Post by shwinny »

My bike is getting a bad surging at idle and decelerating. when i goose the throttle it goes away until i let the throttle go and it surges. I have the sub frame off/ gas tank off/ and the cylinder looks ok. the reeds look ok. Plenty of compression. The 55 pilot jet was kind of clogged so i put in a 52 jet and it still surged. the bike rips really sick when i goose it. and i mean it rips scary fast when i twist the throttle but it is surging at idle and deceleration. .

It has a 170 main 52pilot now it had a 55 which was kind of clogged and its on the third clip from the top. I am stumped on where to go next. the engine was rebuilt 20hrs ago by the previous owner. should i try a leak down test or what not. i hope you guys can help me out. i did try searching but i had no luck.
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Tharrell
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Post by Tharrell »

Crank seals or other air leaks? :)
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CR500PHIL
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Re: surging Idle problem

Post by CR500PHIL »

shwinny wrote:My bike is getting a bad surging at idle and decelerating. when i goose the throttle it goes away until i let the throttle go and it surges. I have the sub frame off/ gas tank off/ and the cylinder looks ok. the reeds look ok. Plenty of compression. The 55 pilot jet was kind of clogged so i put in a 52 jet and it still surged. the bike rips really sick when i goose it. and i mean it rips scary fast when i twist the throttle but it is surging at idle and deceleration. .

It has a 170 main 52pilot now it had a 55 which was kind of clogged and its on the third clip from the top. I am stumped on where to go next. the engine was rebuilt 20hrs ago by the previous owner. should i try a leak down test or what not. i hope you guys can help me out. i did try searching but i had no luck.
Sounds like the change from 55 to 52 pilot maybe your problem. Surging on decelerating is often a sign of a lean pilot - or a lean condition for another reason such as others suggested. If this all started when you leaned the pilot circuit, I would say get another 55 and replace the clogged one you took out.
Steelie Build Done
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AlisoBob
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Re: surging Idle problem

Post by AlisoBob »

CR500PHIL wrote: If this all started when you leaned the pilot circuit, I would say get another 55 and replace the clogged one you took out.
Yup....
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iggys-amsoil
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Post by iggys-amsoil »

Turn the mixture screw in to 1/2 a turn out. :lol:
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2strokeforever
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Post by 2strokeforever »

try a richer meedle straight.... it made my bike a lot better down low
the 450 will have less power and will be harder to start, and will be heavier, but to make up for it it will require more maintenance.
4stroke=dead fish
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100hp honda
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Post by 100hp honda »

2strokeforever wrote:try a richer meedle straight.... it made my bike a lot better down low
if theres a surge down low but the pilot doesnt fix it you think a smaller diameter needle may do the trick ? trying to chase down a problem
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