The valves of my 1960 G9 have been getting far too intimate with the pistons. I thought at first that I had the wrong pistons but having seen the earlier domed pistons I am less sure. My pistons are flat tops.
Any ideas why the contact?
Where there different flat tops fitted?
Getting desperate now, Yamaha`s starting to appeal.
JK
Clashing valves
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- Location: PETERBOROUGH UK
- bjork
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- Location: LEICESTERSHIRE UK
- Location: Leicestershire
Clashing valves
have you checked the valve timing?assuming the pistons are meant for this engine,flat tops should be nowhere near the valves.Are all the valves touching or just one pair or a single valve?I'm thinking along the lines of a sticking valve stem perhaps.Have you been running this engine for a while or is it just built?
Using yesterdays technology to create tomorrows problems today
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- Posts: 42
- Joined: Tue Dec 10, 2002 12:00 am
- Location: PETERBOROUGH UK
Clashing valves
steve,
I have only owened the bike for a couple of months and know little of its history.
The valves that are clashing are the two inlets and the valve timing was OK.
The pistons for the pre-60 G9 are domed and mine as you know I described as flat topped, though they would be better described as slightly domed.
I am unsure as to if these are the correct pistons but I am having trouble getting any information on the correct pistons.
Regards
John
I have only owened the bike for a couple of months and know little of its history.
The valves that are clashing are the two inlets and the valve timing was OK.
The pistons for the pre-60 G9 are domed and mine as you know I described as flat topped, though they would be better described as slightly domed.
I am unsure as to if these are the correct pistons but I am having trouble getting any information on the correct pistons.
Regards
John
- bjork
- Member
- Posts: 1905
- Joined: Wed Jan 01, 1997 12:00 am
- Location: LEICESTERSHIRE UK
- Location: Leicestershire
Clashing valves
as it's both inlets touching,I would want to check the inlet cam timing with a degree disc,rather than rely on the timing marks alone.hope you get it sorted,it's always a bit of a lottery with a 'new' bike.I always seem to end up completely rebuilding everything I buy,and I'm not THAT fussy! I think?
Using yesterdays technology to create tomorrows problems today