can someone please answer? dry float level adjustment.

Does anyone have the base line float height and float drop pre-settings? for an 81 xj750? All I have to work with is sizes 8-19 combination wrenches, screwdrivers & typical stuff, a dial caliper in .001 inches and a standard 1"micrometer. If I had the specs I could measure it before I put it all together, a tuneup + carb overhaul costs more than I paid for the bike and I don't have access to graduated cylnders, bubble gauges or anything like that all I can do is bench set them before I put them together then figure it out as I go, but I don't even know what the specs are or from where to where the measurement is taken. Please help!-------------------

 

carbs upside down. float height specs 17.5mm. base of carb without gasket. measure all 8 floats.

 

I just did this myself and can vouch for these settings.

I cut off the end of a q-tip and measured up 17.5 MM and drew a line around it at that point.

Then I flipped the carbs over so that they are about 60 degrees from vertical with carb number 1 facing me. Presuming you have the floats installed correctly, they should be leaning right against the needle valve but not depressing the spring tip in the bottom of the needle valve. Resting, not pressing.

From the carb base with no gasket installed, I put the bottom of the q-tip touching the mounting base but lined up with the longest jet pole. It should put the q-tip right in the middle of the float area.

Remember how the float would sit in the gasoline? Well, we are measuring the point in the middle of the float that would be touching the gasoline first. Compare the marked q-tip to the middle bottom of the float and adjust the tang accordingly.

I threw the carbs on the bike, fresh gas, checked that I have fuel in all the bowls by loosening the drain screws, fired it up and wham!

All that to say that 17.5 got me fired up and running. Seems to be running well too.

Enter all the folks to will kick my arse for not taking fuel level measurements right away.

 

It would be nice to know what the wet test looked like after your dry set up
When I have set them dry, then checked wet, they have been all over the place.

 

I will get to it. The bike still has a long way to go so I am not in a rush. I just wanted to get the blasted thing running.

 

The only "special tool" needed to check them wet is a 2' chunk of clear vinyl tubing, and maybe some extra fuel line to provide a "remote source."

 

thanks guys, the bike had laid on its side for years when I got it with less than 8000 original miles. I took it apart ad reeamed most passageways clear with tourch tip cleaner files. The pilots were nearly plugged solid then I sprayed gumout through all of the passageways I even miked the files I used to clean with. .120 mains and .028 pilost and it ran well. I know I reamed them larger than that but it ran great from la to vegas and about 6 mos later I rode it to southern Oklahoma. It started missing at about 3/4 throttle in #1 cly about Tucumcari in april. The main jet was clogged & I did the same cleaning routine two weeks ago but now it misses under load at 3 grand in all gears, but I can up shift it to lower the rpms crack the throttle and it'll accelerate to about 3-4 grand then crap out agian. If I back off the throttle a bit it smooths out but going over 60 is a struggle and 70 is impossible. I know the mains are now about 128 and the pilots are fubar so I know I need to rejet agian but in the mean time since it runs good, no black smoke just putting below 4 grand but everytime I twist the throttle more than 25% it acts as if its running out of gas. The bowl drain plugs are all frozen and I don't have a car so I'm going to try re-setting the floats. By all logic it should be rich as heck but its leaning out. Thank you for your advise.