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[Beezabryan]

Float chamber - fuel height? Needle valve?

[Wheaters]

The float height was correct when I first stripped the carb and I always check it before I put the float chamber back on. It was bang in the middle of the two figures quoted in the manual.

The maximum flow through the needle valve itself seems the most likely culprit - I've eliminated everything else I can think of.

[vince]

Hi, does the bike backfire before cutting out? Vince

[Wheaters]

The bike doesn't backfire, it just dies as per running out of fuel.

[vince]

Try raising the float to maximum figure as per spec and see if any difference.Vince

[ed.lazda]

Can't remember if the Mikarb has an inlet filter, but I get exactly these symptoms on my Meteor Minor with a Monobloc carb when the inlet filter clogs up with fine powdered rust from the tank.

[Al]

I had a similar thing with a Bullet 65.Took me ages to track it down but in the end it was just running out of fuel because the float was st too low, closing the needle valve with the float chamber only partially full. With the extra suck a lot of fuel is used and you need the float chamber full all the time. It was very frustrating, a dying engine just when it was really getting going. After a minutes rest, it would fire up again. I went through all the electric stuff as well but didn't need to.

[Wheaters]

The Mikcarb 24 doesn't have an inlet filter. It relies on the usual gauze sleeve around the stack pipe in the tank, a filter gauze screen in a bowl on the base of the tap and if it's like m bike was when I bought it, an additional paper filter canister fitted in the fuel line between tap and the carb. Probably overkill. Mine now only has the stack pipe gauze which has improved the fuel flow, but still not quite enough to prevent the problem from recurring. I will try tweaking the fuel float height up to maximum, as suggested and report back.

[vince]

Hi, check the little plunger on the float needle, if stiff or seized it can effect fuel level. Vince

[Wheaters]

Vince, I'll check that, too. It seemed to be working OK when I last stripped the carb down. My experience of working on various carbs over the last forty years or so is that the spring under the pin often fails or the tip of the needle wears and then the carb floods, obviously this hasn't happened here and there might be other common faults with a Mikcarb. I've put the bike to one side for the next few days (car club rally commitments elsewhere) but will take a look asap next week. Thanks.