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Carb Curve Ball - The bane of my existance! ;) OPINIONS NEED

Fuel System: Gas (Petrol) tanks, Carburators
Sascha
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Post by Sascha » Fri Jan 28, 2011 11:44 am

Hey Davo,

Idle screw - Yes, I can screw it nearly all the way out and it makes very little difference...
No play in the cable at all.. new, yes lubes and its tight with tension.
Whats a plug reading from Idle?

I dont know how to check the intake valuves... please elaborate.

Thanks,
Sascha

Sasha, have you tried adjusting the idle screw to lower idle? Is there any free play in the throttle cable? What is the condition of the throttle cable? New, used, and have you lubed the cable? Have you done a plug reading from idle? Check for intake leak and tight intake valves.

Davo[/quote]

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brewsky
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Post by brewsky » Fri Jan 28, 2011 12:51 pm

Sascha wrote: No play in the cable at all.. new, yes lubes and its tight with tension.
That could be the problem....there should be some slack in the cable and it should not be tight.
Try loosening the cable enough to put a little slack in, and make sure the cable is not catching on something on the frame.

On mine, the slack adjuster had a habit of catching on the frame tab under the tank, and caused the same problem.
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Sascha
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Post by Sascha » Fri Jan 28, 2011 2:01 pm

Interesting... I will check that out brewsky!
Any other input?

-Sascha

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bbap
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Post by bbap » Fri Jan 28, 2011 2:29 pm

Agree, first area I'd review is for an un-obstracted cable and sufficient slack. I would also suggest it may be hanging up on something, perhaps with the cable's oil plug and the frame. This would of course be more noticeable in turning left or right vs., non-turning the bars. Checking is cheap :)
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Post by roadcapDen » Fri Jan 28, 2011 3:07 pm

Turning the wheel right to left may also help check if the cables too tight. ie it'll rev up higher one way or the other sometimes.
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davomoto
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Post by davomoto » Fri Jan 28, 2011 3:17 pm

You should be able to turn the throttle a bit before it engages the slide, or the slide won't be able to bottom out in the carb. Let the bike idle for 5 minutes, once you've got the idle situation figured out, turn the bike off, and remove plugs and check the color. Search on here for valve adjustment, as sooner better than later, they need to be checked and adjusted.

Davo
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Sascha
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Post by Sascha » Fri Jan 28, 2011 3:35 pm

I have aboslutely no idea how to do that... is there a reference you can point me to?

-sascha
davomoto wrote:You should be able to turn the throttle a bit before it engages the slide, or the slide won't be able to bottom out in the carb. Let the bike idle for 5 minutes, once you've got the idle situation figured out, turn the bike off, and remove plugs and check the color. Search on here for valve adjustment, as sooner better than later, they need to be checked and adjusted.

Davo

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