I have replaced Valves & Guides on My Left head and also replaced rings on piston because of Left exhaust smoke and low compression. After completionI had 140 PSI on that cylinder and no smoke. THE BIKE RAN GREAT. Although after 30 miles, the bike returned to its old habit of blue exhaust smoke and after check compression it was again back to 60 PSI. I just cant figure out whats wrong. Please help.
Why would you rebuild just the LH cylinder ? That doesn't compute.
What oil are you running ? What was your ring end gap at assembly ? Have you re-torqued the head and re-adjusted the valves ?
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Yes I Completed the work on Rt Head a few months ago and that all went well.
I've use 20 50 w Castrol reg Oil for 39 years. the bike has 160,000 but new Pistons & rings At 120,00. New Rings at 155,000. NOW Spark plug is Sooty Black on left Cylinder where it is Normal gold on right. The left Cylinder had 140 PSI when 1st tested Cold however after riding after initial warmup , The Left exhaust began to smoke and after rechecked Compression was back to 60 PSI ?????
No I never checked Ring end Gap but cylinder & Piston were Measured OK. Recommended just rings. Tried to re torque the head but made no difference. Could it be a bad or defective head gasket ? Is there oil ports in the head stud sleeves that could cause oil to get into the cylinder ??
Scot,
That is all useful Information. Yes I know about the side stand thing from owning my boxer for half my life but was not aware of the removing the Bing Carb during testing compression. Also the Ring Gap thing is something I want to look into. Tomorrow I will Remove the Carb. Recheck Compression. re torque the head and Check Valve clearance. Run and Test again then if necessary remove the cylinder and see about the Insufficient end gap. I will position rings 180 Degrees apart Although I don't know how to check end gap clearance. Maybe you can Help at that point !
Thanks,
Scott Surdyka
Sorry about the multiple replies As anything else I have a wide learning curve LOL.
Measuring the ring end gap is covered in most manuals. You place each ring in the cylinder one at a time, square to the bore, then measure the gap with feeler gauges. There is a specified gap, and you insure each ring has the minimum, and no more than the maximum.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Hey SB, did you ever get that figured out?
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