Ok guys I'm looking for a way a can diagnose a problem I have. Apparently when I accelerate hard my bike blew out some blueish smoke. I know black smoke is to much fuel and blue is oil. Which isn't good. Can you guys give me some ideas how I can diagnose the problem. The bike does have pipes and air intake. Thank you

 

Check
1. Oil tank overfilled.
2. Oil carryover.
3. Breather hose restricted.
4. Restricted oil filter.

Do a compression test- check your service manual for compression pressure.
2013 XL 1200 is 200-225psi. Older models may be less.

You may be able to get a compression tester (12mm spark plugs) from the Auto Store loan a tool program.

Compression low on first stroke, builds up on the following strokes, but does not reach normal.
Improves when oil is added to cylinder.
Cause: Ring trouble

Compression low on first stroke, does not build up on following strokes.
Does not improve with the addition of oil.
Causes: Valve trouble
Head gasket leak
Incorrect pushrod length

The cylinder leakage test pinpoints engine problems including
leaking valves, worn, damaged or stuck piston rings and blown
head gaskets.

Rotate the piston to TDC of the compression stroke (both
valves closed).
To keep the crankshaft from turning when air pressure is
applied to the cylinder, engage transmission in fifth gear
and lock the rear brake.

Leakage greater than 12 percent indicates internal engine problems.

Listen for air leaks at induction module intake, exhaust pipe and head gasket.
a. Air escaping through the induction module indicates a leaking intake valve.
b. Air escaping through the exhaust pipe indicates a leaking exhaust valve.

 

Blue smoke on hard acceleration is usually bad rings.

 

I will try the compression test and let you know. I hope it's not the rings. The bike just had the whole top end done at the end of last year. Doesnt even have a 1000 miles on the rebuild.

 

With only 1000 miles on a rebuild the rings may not be fully seated yet.
Were the pistons and rings replaced, the cylinders bored and honed?
What was the ring gap set to? Were the ring gaps spaced out at different parts of the bore?




I would still do the compression test.

 

Ok so I did the compression test. I have 90 psi in the front and 120 in the rear. Which isn't good. So would that be rings?

 

Actually reading through the first comment it seems more like valve problems or head gasket. The compression jumped right up to 90 and did not build after that. How do i go about checking valves or head gasket. The head gasket doesn't leak oil. I'm new to messing around with 4 strokes. So valves are new to me but I'm a do it your self type of guy.

 

Try putting some oil in the one with 90PSI and do the compression test again, if it jumps up into the 110-120 range there is a lower end problem.

 

Were the throttle and slide held open during the test?