Float Height

[Boorune]

I have an 81 750F that I took for its first ride in over a decade today. It was mainly firing on 3 cylinders and the three that did fire certainly didn't sound great.

Over the passt few months I've stripped and cleaned the carbs a few times in an ultrasonic bath, replaced float seat and all orings etc. Still running the original jets (68, 102 and 35) in the VB52a carbs. Idle mixture screws were set at 1.5 turns as this is what they already had.

Cylinder had a pressure test and all were consistent at around 130psi. Valve clearance is in spec and spark seemed fine.

Ive again stripped the carbs and checked the float level using clear tube, all carbs are levels are the same, albeit a little high (level with or just under the bowl mounting flange.

A couple of vacuum diaphragms have worn holes, so I just finished plugging the vacuum holes to disable it.

Anyone got any ideas of what else I should check? Could the float level being high cause it to run so poorly?

 

[Boorune]

Its running better after blocking off vacuum, but the fuel level in bowl is still too high. Where can I find quality needles for the floats?

 

[mrtwowheel]

I've been through these carbs 5 times on three different bikes. Two semi- cleanings and all went well. Three total refurbs and all went well. A precise bench synching and they were ready to go. All of these had non-adjustable plastic floats. All of the floats measured slightly out of spec. , but, they all measured the same, worked for me, 5 different times.

 

[Boorune]

I've been through these carbs 5 times on three different bikes. Two semi- cleanings and all went well. Three total refurbs and all went well. A precise bench synching and they were ready to go. All of these had non-adjustable plastic floats. All of the floats measured slightly out of spec. , but, they all measured the same, worked for me, 5 different times.

What needles were you using with the floats? Cheap ebay ones or OEM