Carb Leak Again

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redapple
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Carb Leak Again

Post by redapple »

Hi

Took the bike for a ride this week and it was idling rough and bogging down.
Pulled the spark plugs found two them were covered in black soot/carbon. I cleaned the plugs and started her back up.
I noticed that fuel is leaking from the slider needle were the throttle body is.
I have attached a picture below.
Image

When I push the slider back the fuel stops leaking.

last picture you can see a small puddle of fuel on the butterfly flaps.

Image

Before I do more harm than good thought it better I ask for help

Any help much appreciated
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oldskoolexup
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Post by oldskoolexup »

Have you checked for needle and emulsion tube wear?
Life begins at the end of your comfort zone,
Learn from the mistakes of others.............................
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Teego
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Post by Teego »

Thanks for getting in before me. I say toobs - it always is.
Keep on keepin' on.
redapple
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Post by redapple »

good call. I will have a check tomorrow morning in daylight. I checked the over flow tubes nothing coming out off them.

thank you for getting back:)
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oldskoolexup
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Post by oldskoolexup »

Teego wrote:Thanks for getting in before me. I say toobs - it always is.
Just happened to have an idle moment!

As you say, can't see it would be anything else and would lead to poor/excess fuel metering if worn?

I'm presuming that both should be changed as sets?.......in which case, is there a hardened version available that doesn't wear as readily as brass?
Life begins at the end of your comfort zone,
Learn from the mistakes of others.............................
You can't live long enough to make them all yourself
&
Carpe Diem - seize the moment. Don't dream... Do!
redapple
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Post by redapple »

would a worn float needle valve cause this problem?
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Teego
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Post by Teego »

oldskoolexup wrote:
Teego wrote:Thanks for getting in before me. I say toobs - it always is.
Just happened to have an idle moment!

As you say, can't see it would be anything else and would lead to poor/excess fuel metering if worn?

I'm presuming that both should be changed as sets?.......in which case, is there a hardened version available that doesn't wear as readily as brass?
Yes, Factory Pro stainless steel toobs. I bought a used set from Exup Freak because he couldn't get on with them. Sorted me immediately.
I doubt there will be much wear on the needles as they are steel and the brass toobs pick up all the wear. That was the case for me, anyway.
Keep on keepin' on.
Tipper2
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Post by Tipper2 »

Wear or crap in the needle valve or a sticky float would be my guess.
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YAMAEXUP
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Post by YAMAEXUP »

I bought & fitted new 'toobs' as it was another item on my list to try & find a running fault. Even though the 'toobs' were 48,000 miles old they were as good as new but I fitted the new ones anyway...& it made absolutely no difference whatsoever.

If you've got one of those heat reading devices with the laser pointer, see what each exhaust downpipe is reading. I suspect that the cylinder with the dodgy fuel puddle in the carb is running hotter as the extra fuel in the cylinder will make it run rich.

I suspect that an air leak between the carb & the inlet prt of the cylinder head is leaking. Spray some WD40 around that cylinders manifold & listen for an increase in tickover.

If you find that the revs do rise, then the 'O' rings are available

https://www.fowlersparts.co.uk/parts/40 ... 9-c/intake

Part 9 on the fiche :)
Bikes-they're in the blood.


www.blood.co.uk
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