- Joined
- Oct 17, 2015
- Messages
- 1,962
- Location
- near Harrow, Ontario, Canada
- Bike
- '83 BMW R100RS
- STOC #
- 8870
Hi Dirt Road:
I have followed this thread with great interest because I'm an engineer and engine design is my thing. Having said that, I'm an ST1300 guy so we don't have to content with timing belts. I totally understand your concern about the slight misalignment of teeth count, timing marks etc. and will assure you that there is always a bit of variation from engine to engine and belt to belt. Not as much as one whole tooth, but a bit.
One suggestion I might offer based on my OHC automotive experience (and 1100 folks PLEASE feel free to criticize) would be:
- once you have it all back together and buttoned up as best you can - with spark plugs OUT - turn the engine over in the normal direction of rotation, VERY SLOWLY WITH A RATCHET on the crank (drive) pulley - BEFORE cranking it with the starter.
If the engine rolls over OK, all the way around with nothing stopping it (like a valve clipping a piston), then you should be OK to start it up. If a valve collides, you will be going slowly AND GENTLY and you'll feel it before any harm is done and then you can remove the belt, reset everything and try again.
Be be patient and methodical - you'll get there.
Pete
I have followed this thread with great interest because I'm an engineer and engine design is my thing. Having said that, I'm an ST1300 guy so we don't have to content with timing belts. I totally understand your concern about the slight misalignment of teeth count, timing marks etc. and will assure you that there is always a bit of variation from engine to engine and belt to belt. Not as much as one whole tooth, but a bit.
One suggestion I might offer based on my OHC automotive experience (and 1100 folks PLEASE feel free to criticize) would be:
- once you have it all back together and buttoned up as best you can - with spark plugs OUT - turn the engine over in the normal direction of rotation, VERY SLOWLY WITH A RATCHET on the crank (drive) pulley - BEFORE cranking it with the starter.
If the engine rolls over OK, all the way around with nothing stopping it (like a valve clipping a piston), then you should be OK to start it up. If a valve collides, you will be going slowly AND GENTLY and you'll feel it before any harm is done and then you can remove the belt, reset everything and try again.
Be be patient and methodical - you'll get there.
Pete