ET: Engine (Twin) Mikuni carbs

greg brillus

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Had a customers Comet with a 600 top end kit on it.........we installed a 36 mm Mikuni and after there seemed to be fuel dripping from the clear overflow drain lines......I think the owner ended up lowering the float level to fix it. But I think if the carby hangs slightly lower at the rear, this may cause the problem, as I don't think they like that angle too much. Didn't they originally come factory on Yamaha XT/TT 500's.
 

deejay499

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My solution is similar to others, two T pieces. The rear one goes to the right tap and the front to the left tap. 30mm carbs.
 

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Nigel Spaxman

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Heres two pictures of my bike with two front heads and VM34 mm carbs. I put the battery under the swing arm. There is a tee fitting on the right hand petcock and a tee behind the front carburettor air cleaner. The only filters are the screens in the tank. I have had no problems in 12,000 miles. My floats don't stick for some reason. I have two other bikes with Mikunis and they sometimes stick after being taken out of hibernation. A tap on the side of the bowl usually solves that. The front carb has a special top with a brass pulley to turn the cable 135 degrees quickly with no friction. There isn't much room under the tank.
 

vibrac

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I did note my float needle tip was solid brass I thought they were viton or some sort of rubber tip nowadays?

added at 17.55 Oh Dear its flooding again. So what is meant by 'drilling out the guide holes' in post #23 does it mean the floats or the lever holes? its not clear
 
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Robert Watson

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The floats ride up and down on two small brass pins with holes through the floats, these can have burrs inside them and that is where one needs to clean up the hole.
 

Comet Rider

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The floats ride up and down on two small brass pins with holes through the floats, these can have burrs inside them and that is where one needs to clean up the hole.
Hi Robert,
On my 34mm on the Comet the holes in the floats had a small brass tubes/sleeves in them, but on the 28's on the Rap just as moulded

Neil
 

Chris Launders

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You've got me wondering now, I'm sure my 34s floats pivot on a bar as I've had one that was nipped by the posts after a winter lay up, I shall have to dig the bike out and have a look.
 
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