Carb problem?

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mikeydpippin
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Carb problem?

Post by mikeydpippin »

When throttling off, the carb doesn't slow immediately, the throttle and the carb slide both close fully together and in sync.( you can hear the slide tap onto the carb base when closing throttle with engine stopped)
The tick over when it eventually slows is just right, nice and slow thump.
Its running just a tad too long but noticeable enough when changing gear as it's a bit clunky.
1957 G3
Any ideas?
Mike
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Rob Harknett
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Re: Carb problem?

Post by Rob Harknett »

Check the auto advance unit is not sticking open in the advanced position. While you are looking. give it a good wash out with petrol. Just keep flooding it with petrol while working it by hand. When it stops wishing out rust coloured petrol. Give it a spray of WD 40. You seem to suggest the slides and cables are not sticking. Have you noticed some time it kicks back when it never use to. That would also suggest the AR is sticking. However you do say the revs do eventually drop, so it may only the AR may only be sticking a bit. Revs will drop when it closes fully retard.
mikeydpippin
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Re: Carb problem?

Post by mikeydpippin »

Thanks Rob, that never even crossed my mind, will give it a go👍👍👍
Mike
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Rob Harknett
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Re: Carb problem?

Post by Rob Harknett »

mikeydpippin wrote:Thanks Rob, that never even crossed my mind, will give it a go👍👍👍
Its the simple things that often get missed fearing the worst. Hope it works for you Micky. After 60+ years of riding bikes with SR 1 mags. A spot of cleaning and lubrication has worked wonders. I have never replaced springs. When it really only a spot of cleaning that's the problem. Its inside out of sight where it gets gummed up. You will be surprised how much flushing it takes before the rusty coloured fluid starts to clear. While you have the timing cover off, slip a bit of heat shrink cable sleaving over the metal tags the bob weights strike. It stops that bob weight chattering noise when ticking over. It will last for ages.
mikeydpippin
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Re: Carb problem?

Post by mikeydpippin »

Thanks Rob, cleaned A/R unit but it's still not flicking back, still a bit sticky so will strip down and give a proper clean,
The A/R unit on another bike is solid and not moving but bike starts and runs really well....confused.
Should the A/R unit flick and return easily?
Mike
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Rob Harknett
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Re: Carb problem?

Post by Rob Harknett »

You should be able to open them up to advance, let go and they snap shut. Are yours stuck open shut or...... if stuck open the bike will kick back and not start easy. If stuck shut, bike will be slow, may run hot. Mine got stuck open once, bike a pig to start when cold, kicking back. Took ages to free the A/R with petro/oill
bob121
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Re: Carb problem?

Post by bob121 »

May need a little more slack in the chain
mikeydpippin
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Re: Carb problem?

Post by mikeydpippin »

All sorted Thanks Rob, cleaned and sprayed with WD40 and loosened fixing nut a tad, and now loose and opening as it should.
Thanks for your help, this club is excellent and very helpful because of people like you.
Thanks again,Mike
Mike
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Re: Carb problem?

Post by Dave T_LAPSED »

So that was the "carb" problem and it's sorted now? I would never have suspected that! :roll:
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Rob Harknett
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Re: Carb problem?

Post by Rob Harknett »

Dave T wrote:So that was the "carb" problem and it's sorted now? I would never have suspected that! :roll:
It seems to happen the opposite way round if you have manual A/R. Ride with the lever retarded when the engine's hot and it just don't want to pick up revs. and go
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