Revs all over the place....? Help

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Sam
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Revs all over the place....? Help

Post by Sam » Wed Aug 04, 2010 5:50 pm

I recently cleaned the carbs and fitted them. Got it running. I found that after 4k the revs are fine and pick up just fine but as soon as i get off the throttle and get to 4k rpm it doesnt get back down to 0rpm easily and once it gets the needle just moves up and down a fair bit.

What could it be? The vaccum hose has been renewed.

Thoughts?

Thanks.

Neosophist
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Bike owned: CBR954

Re: Revs all over the place....? Help

Post by Neosophist » Wed Aug 04, 2010 6:25 pm

Air leak between the carbs and the engine.

Happens a lot on old rubbers. While it's running if you blast around the rubbers with brake / clutch cleaner or easy-start (somethign flammable) you'll find the air-leak when the RPM's change
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

Sam
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Joined: Wed Apr 30, 2008 5:20 pm

Re: Revs all over the place....? Help

Post by Sam » Wed Aug 04, 2010 8:24 pm

Neosophist wrote:blast around the rubbers with brake / clutch cleaner or easy-start (somethign flammable) you'll find the air-leak when the RPM's change
Whats happen after spraying this stuff if there is a leak? Bubbling?

Harvd
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Re: Revs all over the place....? Help

Post by Harvd » Thu Aug 05, 2010 7:53 am

Your revs should jump up

Neosophist
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Re: Revs all over the place....? Help

Post by Neosophist » Thu Aug 05, 2010 11:03 am

Neosophist wrote:Air leak between the carbs and the engine.

Happens a lot on old rubbers. While it's running if you blast around the rubbers with brake / clutch cleaner or easy-start (somethign flammable) you'll find the air-leak when the RPM's change
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

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