81 carb float levels

[motoman]

Hi all! know I've seen it here before, but can't find it, so maybe you can be of help. What is the correct float level settings for carbs on an 81 xs Venturer 1100? Is there any compensation for altitude? I'm at 4,800 ft., and mostly ride up from there. The mains are 105's as stock would originally have been 110's. I realize that is only a half step lower as five numbers = 1 whole step. Compression is low (90 on #1 to 115 on #4) but really didn't want to change jetting as I am using carb bank on a replacement engine. Most likely going to do valve adjustment before pulling engine, so as to give the beast a chance to rectify itself, and know exactly what internally is the culprit, whether it be valves or rings.....or both. So if you know that setting, let me know as I am ready to put carb bank back on any try it before dark-thirty.....Thanks all for all the great input! Seem to remember 27mm, which is 1.06inches......not sure tho....

[TopCatGr58]

The 81 were actually set lower/richer due to the smaller jets, around 23mm, but due to your altitude, you may want to try a little higher to be leaner, but not 27mm. The earlier models were 25.7. Also the 105's are 2 steps leaner, they are in 2.5 increments! As for your compressions, they might not be as bad since you're at altitude compared to if you were measuring at SEA LEVEL!? Plus, if you haven't had a chance to drive it, you may have some rust, or slightly sticky rings, but once you run it a while it might scrub the cylinders, and reseat the rings!?

Try the carbs and run it a while and then recheck before tearing into it!? T.C.

[motoman]

81 carb float level

Thanks for the info on that T.C. Whil I was waiting for some info I converted the MM to inches from google thing and 27mm is 1.06 inches.
Based on that, the floats were a 1/4" higher than 27mm. It never has run fuel over, but felt that was a little high. The bike has always been ridden "ocassionally", and I have ridden it some 200+ miles with having to pull plugs and use my plug cleaner (silica sand, with compressor) you know what they are, bout every 50 miles as it starts dropping cyl. Plugs are heavily carbon fouled, with #1 being a little oil fouled on top of carbon fouled, as that cyl. is the lowest on compression. Have'nt put carb bank on yet, so I'll go back and raise them some from the 27mm I had set them at. Havin the valves checked and properly shimmed(shop I'm gonna use has a person there I've known for years, and knows the xs's well being factory trained when these bikes were king of the boulevard, and has lots of the shims as same ones are used on "todays" applications too. That very well may raise that compression by opening valves all the way, also doing automotive for 35+ years, altitude has no effect on compression, just vacuum, approx. 1 inch for every 2,000ft in elevation. The bike thing definitely has its differences, but still is just an air pump with fuel and spark added at the right time. 1 millimeter= .0393700787 of an inch, so at least were only talkin' a tenth difference from 25mm to 27mm. Thanks again for clarifiyin' that on the 81 H !