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Author Topic: high idle or nothing  (Read 815 times)

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Offline hymodyne

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high idle or nothing
« on: May 09, 2013, 06:56:01 AM »
I have been riding this bike for two or three years with no issues, now i cannot get it to idle below 2500. when I try to adjust the idle below that, the bike cuts out. I took the carbs off, inspected each float bowl and low speed idle jet, as well as the linkages for each. Bench synched the carbs and replaced the o rings on the intake manifolds, still It will not idle properly.

Any help would be appreciated.

james
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Offline flybox1

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Re: high idle or nothing
« Reply #1 on: May 09, 2013, 07:12:34 AM »
what do your plugs look like?
i'd think it was starving for air or fuel...
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Offline Rookster

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Re: high idle or nothing
« Reply #2 on: May 09, 2013, 07:44:38 AM »
Your slides could be too low. 

This board can make you second guess yourself.  My carbs had been synched and were working fine but I was nervous I had too many threads showing on the top of the adjusters.

There was another thread where someone bench synched their carbs on the bike by bottoming out the slides (loosen the adjuster screw until the slide cannot be pushed down anymore).  I tried this to see if it would work.  It didn't.  I couldn't get the bike to idle at all below 2500 - 3000 with the slides completely closed, where it idled fine before I touched it.

I turned the adjusters to only have 1 thread showing on all slides then hooked up gauges.  Bike idled fine at 1100 again and with a few tweaks it synched right up. 

Worth a try.

Scott
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Offline hymodyne

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Re: high idle or nothing
« Reply #3 on: May 09, 2013, 08:00:34 AM »
Quote from: Rookster on May 09, 2013, 07:44:38 AM
Your slides could be too low. 

This board can make you second guess yourself.  My carbs had been synched and were working fine but I was nervous I had too many threads showing on the top of the adjusters.

There was another thread where someone bench synched their carbs on the bike by bottoming out the slides (loosen the adjuster screw until the slide cannot be pushed down anymore).  I tried this to see if it would work.  It didn't.  I couldn't get the bike to idle at all below 2500 - 3000 with the slides completely closed, where it idled fine before I touched it.

I turned the adjusters to only have 1 thread showing on all slides then hooked up gauges.  Bike idled fine at 1100 again and with a few tweaks it synched right up. 

Worth a try.

This sounds like a fix. When I checked the slides, they were all at the same level, but there was virtually no space at the bottom of the slide. I will re-synch and adjust upward the slides.

james

Scott
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Offline iron_worker

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Re: high idle or nothing
« Reply #4 on: May 09, 2013, 10:44:18 AM »
Adjusting the slides upwards can really only bring the idle up ...

I would be checking your pilot jets very carefully for plugging. Did you pull them out?

What are you idle mixture screws set at?

Have you done any testing with ether or propane to check for vacuum leaks?

Are your throttle cables hanging up?

IW
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