Ta, I find I like this compliment, when I adventure into good, tricky or skilful things with care and so on, much like my young son does! Whats more, I'm new to the ducati forum too, and am growing fond of the community - I'm now looking forward to meeting up with you. I hope to get my bike on the road shortly, tested and meet up this year if all goes smoothly.
If you have been checking clearances with the piston at TDC, then you decide to take the belt off and turn the camshaft round to see if it binds ... I hardly need to mention this ... but please move the piston down the bore before you turn the cam.
Some times people stone a shim down on a grinding stone to take off a whisker (say 0.01mm). You never know if that has been done with the shim in front of you. So it is advisable (read essential) to measure each shim with a micrometer as you are using it just to be certain.
Surely I only need to gently rock the camshaft around TDC to check for bind, i.e. when the closer is on the cam. The head is surely internally dished... ?!
No, you need to turn the camshaft through 360 degrees, so it fully opens and closes the valves. It must not bind anywhere around the circle. If the camshaft has a bit of wear (or was not made totally accurately in the first place), the relationship between the opening and closing profiles may not be 100% perfect all the way round. It might be free somewhere but a bit tight somewhere else. It is inadvisable to take it for granted if you have a chance to check.
OK gotcha Pete. Thanks. I've been through the process, and can report no binding. I found the closer spring to work well, and now have avery very slight bit of closer spring depression at TDC. I think the belt may have been a tooth out.. it appeared to be when dismantling... Started up fine, although playing around beforehand I had risked losing the left-right cylinder ignition line up, , checking TDC marks against piston travel, observing in practice how the cams etc were configured for the 90 degree twin cylinder engine, new to me, and NB should you follow this thread in practice, when, with belts removed, where to rest the vertical cylinder's cam with both valves closed on firing stroke BEFORE moving the pistons down and the checking cams for bind. I was lucky with the ignition this time! Couldn't be bothered to look into it with a meter and cam observation, tuning the wheel in gear... I was prepared to swap the leads round.... which I have never preferred normally, only because it takes a while is tiring to learn about Italian desmodronics for real, when you find many accounts but fewer assured or even comprehensive enough for your needs... I guess conceptual difficulties remain in the national consciousness for that reason ... Thanks all you good folk. Forks are now rebuilt and refitted too, and shall soon be ready for road test.
