Mr Vegetable Trousers
Junior member
- Location
- London, UK
Response from Keith Nairn with an interesting observation on 750 cylinder blocks and liners.
His pricing for the rebore and the work to the liners was very reasonable, the new Omega pistons are pricey but I cant really do without them!
Had a look at your barrels today and they will require a rebore due to the depth of the corrosion. We will also need to reset the liners, I am finding this on almost all of the old 750's now. The main barrel casting shrinks over time leaving the top face of the liners slightly proud, this prevents correct gasket sealing and eventually leads to oil leaks. Not a major problem to fix but it does involve a couple of hours labour to remove the liners from the barrel, machine the top of the barrel flat again then recut the counterbores to allow the liners to sit at the correct height relative to the barrel face. The liners are then refitted and bored then honed to suit the new pistons.
His pricing for the rebore and the work to the liners was very reasonable, the new Omega pistons are pricey but I cant really do without them!
Had a look at your barrels today and they will require a rebore due to the depth of the corrosion. We will also need to reset the liners, I am finding this on almost all of the old 750's now. The main barrel casting shrinks over time leaving the top face of the liners slightly proud, this prevents correct gasket sealing and eventually leads to oil leaks. Not a major problem to fix but it does involve a couple of hours labour to remove the liners from the barrel, machine the top of the barrel flat again then recut the counterbores to allow the liners to sit at the correct height relative to the barrel face. The liners are then refitted and bored then honed to suit the new pistons.
