The Mighty Garage 1951 Vincent Rapide - Part 006: Bore Inspection
- Thread starter Mike T
- Start date
Ive seen this a few times. Looks like you've got corogations in your bore that will unseat the rings and cause loss of compression and high oil consumption.
Easily fixed with a rebore noting that you're already at +040".
Easily fixed with a rebore noting that you're already at +040".
Most likely the honing has not removed the machining marks from the boring of the cylinder.
Agree with you there Greg.
From the in-cylinder video it looks to have been run for quite a few miles after the last rebore.
These corogations don't 'heal' and the piston rings simply can't seal.
How do I know? Well, I helped a colleague by replacing the cylinders and pistons in his Rapide that looked just like yours that transformed it from being incapable of exceeding 70 mph to returning to normal service.
From the in-cylinder video it looks to have been run for quite a few miles after the last rebore.
These corogations don't 'heal' and the piston rings simply can't seal.
How do I know? Well, I helped a colleague by replacing the cylinders and pistons in his Rapide that looked just like yours that transformed it from being incapable of exceeding 70 mph to returning to normal service.
Some things are best Not known !, 
.
If I had one of those, I would not ride any of my Bikes !.
.If I had one of those, I would not ride any of my Bikes !.
The circular grooves in the 1st cylinder is a bad rebore then there are a lot of vertical scratches in the 2nd bore, and looks like it has been run for quite a while, then glaze busted and new pistons fitted.
Not sure what I would do though, I think if I wasn't stripping it for any other work I think I would give it a try, but if it needs any other work then new liners and pistons back to standard.
Not sure what I would do though, I think if I wasn't stripping it for any other work I think I would give it a try, but if it needs any other work then new liners and pistons back to standard.