I have now put over 5,000 miles on my Comet since the major rebuild that did NOT involve splitting the cases, but did include a new piston and liner.
On a ride yesterday I thought I heard a new noise – a rhythmical knocking that changed frequency with engine speed but could only be heard on a neutral throttle – as soon as I rolled on even slightly positive throttle the noise was no longer audible (well not to me) and conversely, if I rolled off the throttle – engine braking, again the noise was no longer audible. In all other respects the bike is fine – runs very well, uses little oil and handles as well, if not better, than my 2013 Moto Guzzi V7.
It sounded like big end knock in a conventional slipper bearing motor. Oil level is fine, and the oil pump is doing its thing, likewise the tappets are at their correct (none) clearance when cold. Is this just me getting more and more accustomed to the bike – or could it be something to worry about? I have also checked the quill and it is intact and clear. I also removed the sump plug and inserted a magnetic wand which picked up a few wiskers of metal - though I think they came from the very worn valve stems - they were worn to a letter "D" profile due to misaligned guides - and this was fixed about 2,000 miles back.
Any suggestions???
Tempting fate – tomorrow I am heading off on a 400 mile 2 day trip. It is a shakedown for a 2 week-long tour in the second half of March when, along with 100 other pre 1955 British Bikes, I will be riding around Tasmania, with an expected total of 1,400 miles to be covered over 12 days (that EXCLUDES the ferry trip J).
Martyn
On a ride yesterday I thought I heard a new noise – a rhythmical knocking that changed frequency with engine speed but could only be heard on a neutral throttle – as soon as I rolled on even slightly positive throttle the noise was no longer audible (well not to me) and conversely, if I rolled off the throttle – engine braking, again the noise was no longer audible. In all other respects the bike is fine – runs very well, uses little oil and handles as well, if not better, than my 2013 Moto Guzzi V7.
It sounded like big end knock in a conventional slipper bearing motor. Oil level is fine, and the oil pump is doing its thing, likewise the tappets are at their correct (none) clearance when cold. Is this just me getting more and more accustomed to the bike – or could it be something to worry about? I have also checked the quill and it is intact and clear. I also removed the sump plug and inserted a magnetic wand which picked up a few wiskers of metal - though I think they came from the very worn valve stems - they were worn to a letter "D" profile due to misaligned guides - and this was fixed about 2,000 miles back.
Any suggestions???
Tempting fate – tomorrow I am heading off on a 400 mile 2 day trip. It is a shakedown for a 2 week-long tour in the second half of March when, along with 100 other pre 1955 British Bikes, I will be riding around Tasmania, with an expected total of 1,400 miles to be covered over 12 days (that EXCLUDES the ferry trip J).
Martyn