#1 Cylinder weak

[davez]

After owning my '85 for about two years, I finally have it on the road (put on about 3000k) and it seems to run fine, but I don't have anything to compare the performance to as this is my first bike. Power wize I don't seem to have a problem overtaking a friend's '04 V star 1100. I do seem to have a weak #1 cyclinder because if I take off the spark plug wire at idle, there is no RPM change. I know it fires because if that is the only plug wire attached the cyclinder does fire. I did a compression test and it came in at just 130 (after 10 cranks) and up to 150 with some oil. The others seem to be at 150 -160 after only a few cranks. I checked valve clearance and they are right on. I'm thinking the rings are the problem. I read somewhere on this forum about using Sea Foam in the oil for sticky rings. Does this work? I think the bike sat for a number of years so it could be the problem. Is there any suggestions to trying this before I pull it apart?

[GeorgeS]

Deffinatly run the Sea foam for Several Tanks of fuel. Give it severall tanks and time to work. At least do this before you tear anything else apart.

 

Have you pulled out the Carb Diaphrame and checked it for condx, and small holes.

 

Pull that plug wire out, and Trim about 1/4 inch of copper wire off each end, and rescrew them back in. Both ends, at the Coil, and the plug cap. Possible high resistance contact here.

[Cutty]

Because you have fire there, check out the carb for clogged pilot jet and sync. The compression might improve by and oil and filter change with M.M.O. added to oil. A valve adjustment wouldn't hurt either if the above doesn't cure problem. So lets put 500 miles a day on it and see alot of changes.

[Denden]

I'd try some Seafoam inthe GAS, not in the oil. Pour in a whole can to a full tank of REGULAR gas. Do it a couple of times. And run her HARD. Some things that can cause a buildup of carbon are using Premium gas and riding real easy, always shifting at low RPM's, never going to full throttle, and idling a lot. This V4 likes to be run hard, and use the rpm's, go to redline at full throttle once in a while, when conditions allow. It keeps the combustion chamber, valves and rings clean.

[davez]

I think I will go and try some of this MMO. It seem to have worked for others and it's an easy thing to try. I did rebuild all the carbs and yes all the pilots were blocked. Even went over the #1 carb a second time to make sure it was okay and it is. I am hopeful with some treatment oil and some milage this thing will clear up. It's great if riding results in fixing!