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i use a clear hose attached to the float bowel drain to observe the actual level
in fact i ride with them on the carbs
i route the hose up the side of the carb u bend it straight down so water cant get in
makes for a quick diafgnosis check if out riding and having fueling issues
on the vm mikuni as well as the keihins you want the level to be at least 6mm below gasket
if you have a pamco in there yank it off and put the points back in you have to or you could go mad chasing a carb problem that is really an ignition issue
the pamco is good unit but they fry easy from simple little wiring snafus

And I set them to 3-4mm below the gasket surface - no lower.

The answer is that if you set fuel levels and not FLOAT levels you will be far more able to adjust them and see the effects. Your fuel levels will also be much more accurate.

CrazyPJ has some CB360 carb synch tubes in 6mm x .75mm that happen to match many smaller sized Mikuni and Keihin float bowl drain screws.
 

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Discussion Starter #22
Well finally got my new jets and jet needles and stuff in to try the new set up on the Mikuni VM carbs. This setup is almost perfect! Runs great all the way thru the mid range and idles perfect. Feels a little rich on the top end but no spitting or missing just feels a little slow to accelerate. I will try a 195 main and see how it feels. I really appreciate all the help from you guys getting this bike straightened out. On another note, I have ordered some first over pistons and rings for the 1969 Yamaha R3 and will let you know how that project goes. Again, many thanks.
 

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... Feels a little rich on the top end but no spitting or missing just feels a little slow to accelerate. I will try a 195 main and see how it feels....
then just drop the main jet needle by one notch,
changing the jet size will affect a change throughout the whole operating range, changing the needle position changes only the 1/2 to wot operation.
 

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then just drop the main jet needle by one notch,
changing the jet size will affect a change throughout the whole operating range, changing the needle position changes only the 1/2 to wot operation.
As far as I know adjusting the needle height only effects 1/4 to 3/4 throttle.
 

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Discussion Starter #27
Well after doing a plug chop, it looks like it is too lean so I am going to go to 210 mains. (yes I know I should try the 205's but I don't have them so I will try what I have and go from there.) The needles are in the highest position so bigger jets are the next option. If the 210's are too rich I can send for the 205's and play with them and the jet needle and get it just right.
 
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