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Newly overhauled engine.
Also the valve guides..
And a omega/accrlaite piston with a build-in clearance of 0,07 inch..
In the metric system it is even more scary; 0,11mm!

Normalyy that's 'worn out'?
Anyway, after about 1200km's running in i had to fill up the oil 2 times with 0,5L..

And yes, i do not understand and it worries me a bit.

Has anyone corresponding experience with this piston?
O.11 mm is 4 thou, (0.004) which would be in the ballpark for a new piston.
If Omega are asking for 0.007 (7 thou) = 0.177 mm it does appear quite a large clearance but it all depends on the piston expansion qualities. Omega should know what their producs require.
Just a thought, going back quite a few years. when we were running Accralite pistons in our 500 racer on + 0.020" size, I had to replace a piston quickly before a race meeting and ordered one and fitted it as soon as it arrived. At the race meeting, the bike performed fairly well [surprisingly], but rattled, smoked and spewed oil from the breather. Back at home, I stripped the top end again to check and I found a standard bore size piston in the oversize bore - A standard piston had somehow found its way into a box marked +0.020"!
Worth a check?
I seem to recall Omega pistons for Velocette Venoms required .0045" clearance.And the original pistons .004".
And i do recall a friends RE Bullet lightning he fitted with an Accrillite at.0065" and Alloy barrel and it sounded
terrible whenever he took off down the road,the rattle was very noticeable.
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