Snapped belt

Nasher · 31-07-2022, 04:59 PM

I pulled the head today to see what the damage is.

There is a definite mark across the straight edge of the Exhaust valve cut-out in the top of the piston:
(Ignore the sideways scratches, that was me with a fibre rod down the plug hole the other day to show when the piston was going up and down)

And a corresponding mark across the Exhaust valve head.
Note the valve has spun round:

The easiest way to see if there was any gaps between the valve head and seat was to turn the lights out and shove a small pen torch up the Exhaust port to see if any light escapes:

Then spin the valve round 90 degrees to see if the light leakage moves, which it did:

And then the light can't be seen with the mark towards the camera.

31-07-2022, 04:59 PM	#1
Nasher Registered User Join Date: Jul 2014 Location: Portsmouth Bike: M900 Posts: 1,510	I pulled the head today to see what the damage is. There is a definite mark across the straight edge of the Exhaust valve cut-out in the top of the piston: (Ignore the sideways scratches, that was me with a fibre rod down the plug hole the other day to show when the piston was going up and down) And a corresponding mark across the Exhaust valve head. Note the valve has spun round: The easiest way to see if there was any gaps between the valve head and seat was to turn the lights out and shove a small pen torch up the Exhaust port to see if any light escapes: Then spin the valve round 90 degrees to see if the light leakage moves, which it did: And then the light can't be seen with the mark towards the camera. __________________ Heaven doesn't want me, and Hell is afraid I'll take over. Last edited by Nasher; 31-07-2022 at 05:01 PM..