Rear wheel & carb question

[Bluntest]

Hello everyone,

I just got an XS1100 1981 so I'm brand new to the bike. So I have a few questions.


The bike is basically unmovable while sitting on it, it takes 2 to move because the rear wheel is very hard to turn. It gets slightly easier if I remove the caliper but should still turn easier. I assume this is either the drive shaft or the bearings. The rear bearings seem to be unsourcable so I'd like to know where I can get some/what my options are.

Second problem is carbs seem to be spitting fuel back out the airbox because I have fuel leaking out of there. I took it around the block plenty of times and then one time I started the bike is just started leaking.

Thanks!

[Socer4m]

howdy,,,,check the tightness of the rear axle bolt,,,maybe its way too tight, so try loosening it and see if that helps, also check it in nuetral, and also check front wheel for easy spinning. As far as carbs, pop them off and do a thorough cleaning and check the floats for even height from the carb body., these old xs1100s all leak gas until the cleaning and or rebuild is done. YOu could get lucky and try banging on both sides of the carbs with a soft hammer to free the float. Also make sure there are inline gas filters on each line coming from the gas tank as any crud will cause carb leaking without them.......muy importante......good luck, keep us informed,,,Mike in S.Diego and Pa.

[Radioguylogs]

Are you moving the bike neutral, or is in gear with the clutch lever pulled? I'm asking to see if the clutch is the issue.

Your gas leak might be caused by dirt on the float needle valve, or a stuck float. If it doesn't clear by rapping a screw driver handle on the float bowls, then the carbs will probably have to come apart to clean the float needle valve.

In the meantime, I have flushed debris from the float needle valves by:
(1) Turn off the fuel petcocks
(2) Put a bowl or pan under one of the carbs
(3) Remove the carb float bowl drain plug (or open the drain screw if applicable)...some gas will come out then stop
(4) Open the fuel petcock until more gas comes out- then close it
(5) Replace the float bowl drain plug
(6) Repeat for the other carbs

Remember, if your petcocks are left open or fail, and the carb float needle valves continue to leak, you can leak gas into the crankcase. If it happens and you run the engine, it will ruin the crankshaft bearings quickly.

[Tonyxs11]

if the float needles are the original ones then its time for a new set, just replaced all mine with a kit, they come with the seat as well.

[Bluntest]

Thanks guys. I will try all that has been recommended and report back.

[pete_s]

Rear wheel will not move if rear caliper piston / cup is corroded. I've had to wack one to pick up a XS11 this year with a hammer and block of wood. Seller was impressed as he had been trying to move it for awhile. It needed all 3 calipers cleaned and new cups as hard chrome was pitted.

Definitely have to clean the carbs and install factory Mikuni needle and seats to last another 40 years. I don't think the engine will fill with gas but the air filter and box sure will.

A full carb rebuild will include pulling the slides and diaphragms, main jet, needle jet (push out to clean all the holes) and don't mix or swap the parts. You can record the part numbers to a diagram as they may have been worked on. Watch the diaphragms as they may be shrunk and hard to reinstall if the bike has not been run in years. Good USA ones are $25 apiece, china one are cheep

Pull the fuel lines from the carbs and put lines in a container to see if the shutoffs are leaking and need rebuilding.

Good news is the rest of the bike is reliable and good on gas with the stock ram tube air box, exhaust. Get it going!

[Bluntest]

So I cleaned the carbs and the bike works fine now. Thanks guys.

I took the rear caliper off the disk and the wheel turns a lot more freely. The front tire is also difficult to turn so I'll be trying without the calipers there as well. If my discs are the issue it seems my only option are brand new ones for around 250$ each? Do I have other options?

[DiverRay]

It is probably NOT the disk! Use a dial indicator to check runout, or, just use a pencil, spin the rear wheel, and see if you have a solid line on the rotor. You NEED to completely rebuild the brake system before spending money on other parts. This is master cylinders, brake calipers, and new brake lines, as the 40+ year old rubber lines are probably shedding gunk into the system.

[Bluntest]

It is probably NOT the disk! Use a dial indicator to check runout, or, just use a pencil, spin the rear wheel, and see if you have a solid line on the rotor. You NEED to completely rebuild the brake system before spending money on other parts. This is master cylinders, brake calipers, and new brake lines, as the 40+ year old rubber lines are probably shedding gunk into the system.

I will look into this and report back. Very much appreciated!

[Tonyxs11]

if the wheel is tight to turn its the calipers, what happens is corrosion gets under the seals and builds up, it then pushes the seal tight on the piston and stops is from retracting, hence the binding.
ive stripped countless calipers over the years and most of the time all i did was clean everything up, ive replaced seals just a handful of times so a good chance your seals will be ok to reuse.