Carbs off

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mick.mh2racing
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Carbs off

Post by mick.mh2racing » Sat Nov 27, 2010 11:21 am

Here's one question I think I already know the answer to.
I had my carbs off yesterday and gave them the Cammo treatment, cleaned out the emlsion tubes, jets, drilled the slides by 0.5mm and raised the needles to 1.0mm. Firstly thanks Cammo,your guide is invaluable.
Question is how do the float bowls fill up again? Are they gravity fed so as long as the fuel tap is on, they'll fill up by a process of gravity?
Or is a question of turning the bike over on the starter and the vacuum created will fill the bowls?
As a precaution I've had bike on charge overnight!
How hard can it be?

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CMSMJ1
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Re: Carbs off

Post by CMSMJ1 » Sat Nov 27, 2010 1:14 pm

A quick couple of blasts on the vacuum will send enough fuel down to fill them up - you'll be reet ;)
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The V4 is the law..

NC30 - No9 - my old mate

mick.mh2racing
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Re: Carbs off

Post by mick.mh2racing » Sat Nov 27, 2010 3:08 pm

Cheers Mark, bike started fine. Didn'trellycurethe problem I'd hoped though. On tickover it seems to hunt, only slightly. I seem to be always adjusting the tickover.
Next step is to squirt a bit of brake cleaner at the inlet rubbers and see if revs rise a bit. Other than that I'll have to polish up my carb balancing skills. When I'm nailing it bike goes fine but when I come back it seems to inevitably stall.
Carbs were fine when I've had a look. Emulsion tubes were back to front, that's about all.
How hard can it be?

Neosophist
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Re: Carbs off

Post by Neosophist » Sat Nov 27, 2010 3:59 pm

Hmm.

Did you check float heights / pilot screws?

Stalling when returning to idle can indicate a rich mixture...

If you set the idle to around 1000rpm, rev the throttle and let it go back to idle, does it return cleanly to idle, hesitate before it goes back to idly (especially around 2000rpm) or does it drop below idle then come back up again?

Idle speed is best set warm..

An uneven tickover can also be balancing so best get some vaccumn gagues on there and check the balance.. but unless they are realllly out it shouldn't make it stall ...
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...

mick.mh2racing
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Re: Carbs off

Post by mick.mh2racing » Sat Nov 27, 2010 5:00 pm

Did pilot screws at 2 and a quarter out. Didn't check float heights.
I ran bike till it was hot and set tickover at about 2000rpm, reved it a bit and sometimes it would return pretty much straight away and other times it seems to be hunting around 1500rpm. A couple of times it tried to stall.
As it's hunting my thoughts are drawing air, probably through poor sealing around the intake rubbers.
How hard can it be?

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