is this a piston ring problem

GREASER

XS1B CHOPPER
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ok back again with more problems when bike is on idle it sounds like the left side is not fireing correctly and throws out warm air and un burned fuel and right side is hot sounds good when i rev it it works but kind of back fires not loud but out seqence and also this is the part that really caught my attention the breather on top of the motor was thowing out hot air and not to sure but had a smell of gas to it i was thinking it was a piston ring but hoping for more opinions bike is a 1971 xs1b :banghead:
 
- check if you have petrol in the sump...if so indicates badly set up carb...float not set properly, float needle seat kaputt, o ring broken...apart from that do a good cold set-up
 
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- check if you have petrol in the sump...if so indicates badly set up carb...float not set properly, float needle seat kaputt, o ring broken...apart from that do a good cold set-up

the carbs were rebiult not to long ago so that had me thinking i ran the bike till there was no fuel in the carbs and removed the carb to check the float and it looked good i blew air threw the line with the needle open and went threw then with needle closed and no air passed threw dont know if that was a good idea and also what do you mean by sump the bottom of the carb if so it has a over flow right it would over flow alot for some reason its not doing it now it happens once in a while i really hope its just a carb problem im going to check the compression today any ways just to be sure on that to so what do i do if the sump has petrol
 
- sump...oil, lower engine casing...these carbs will leak if the floats are not set properly, or if the float needle seat is damaged or if the o-ring is damaged...the gas will leak into the filters or end up in the oil

- check the oil-hopefully it doesnt smell of petrol, and do a cold set, this will make sure the cam, valve and ignition timing are all more or less where they should be...after this your problems will be electrical, carburettor, rings-cylinders, head gasket, worn valve seats and or seals

- are your rings properly gapped

- 1st ring, top...height 1.2mm, 0.047in...end gap 0.2-0.4mm, 0.008-0.016in...ring groove side clearance 0.04-0.08mm, 0.0016-0.0031in​

- 2nd ring...height 1.5mm, 0.059in...end gap 0.2-0.4mm, 0.008-0.016in...ring groove side clearance 0.03-0.07mm, 0.0012-0.0028in​

- oil ring...height 2.8mm, 0.110in...endgap 0.3-0.9mm, 0.012-0.035in​

- also the gaps shouldnt all be above each other, but staggered
 
floats leak and sink, also. soldering them is next to impossible.
 
When they are in the dip tank and one sits lower in the solution than the other, it's a dead give away. I missed it the first time or it was not leaking, then it leaked. Back off with the cards, Soldered it, must have left a pin hole and had to take it off the bike again. Put a new float in from Mike's after that.
 
Greaser, what do the spark plugs look like when you compare the left one to the right one? If the left is gas fouled you possibly have an ignition problem in that cylinder either being a bad spark plug or bad plug wire etc. Usually bad rings will allow oil up and into the cylinder where it will burn blue smoke out the exhaust until the plug gets oil fouled. An oil fouled plug will look dark and crusty. Try a compression test on each cylinder and if possible a cylinder leak down test to determine the condition of the rings. Start with the simplest of things like the plugs and go from there..........BG
 
See Greaser they have a lot more answers and explanations than I could even think of. I could have only told you what my problem was and yours doesn't sound like it was the same as mine.
 
See Greaser they have a lot more answers and explanations than I could even think of. I could have only told you what my problem was and yours doesn't sound like it was the same as mine.

well you did give me a good answer" put it up on the board "is what you said well will do everthing possible to get this bike out on the road this board kicks @ss :thumbsup:
 
When they are in the dip tank and one sits lower in the solution than the other, it's a dead give away. I missed it the first time or it was not leaking, then it leaked. Back off with the cards, Soldered it, must have left a pin hole and had to take it off the bike again. Put a new float in from Mike's after that.

well one side did sit higher than the other side just a little
 
Greaser, what do the spark plugs look like when you compare the left one to the right one? If the left is gas fouled you possibly have an ignition problem in that cylinder either being a bad spark plug or bad plug wire etc. Usually bad rings will allow oil up and into the cylinder where it will burn blue smoke out the exhaust until the plug gets oil fouled. An oil fouled plug will look dark and crusty. Try a compression test on each cylinder and if possible a cylinder leak down test to determine the condition of the rings. Start with the simplest of things like the plugs and go from there..........BG

the plugs are pretty new im using NKG B-8ES the plugs when i pull them out they look black but not crusty no oil on them at all when i pull the wire off the plug you can here the differance when its back on it fires but maybe not enough spark one thing i mentioned to INSX the points i replaced them and put them on just like that is there suppossed to be a certain messurement like a gap cause i just threw them on there :confused:
 
Greaser, first of all, you need a manual. Then read it through. Your point's & ignition timing are all related to each other. If your point's are not set correctly, your timing is definately off. A manual will inform you how to set the points up right. Then how to set the timing.I do believe there is a link to a manual here somewhere.And it's free. Good luck, & keep us informed on how it's going.,,,Gordo:):bike: The manual is located in the tech file, about 3/4 of the way down.
 
Greaser if your spark plugs are new and black thats soot from a rich fuel mixture which can be caused from incomplete combustion that can be the result of you installing points without properly setting the gap. Gordon is correct, you need to read and understand the manual then properly set everything up according to the specs for your particular year engine. Its not that hard to do just takes a bit of time and patience and willingness to learn. The end result will be a good running machine that you did yourself............BG
 
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