Speeddog, what Ivan has said is not wrong but he’s missed something so let’s start again, fitting a new belt then right through 12k miles to the next belt change.
You set the crank at tdc compression on horizontal cylinder; lock both cams either using the Ducati tools or, like me, using 6mm dia bar through the screw hole in left side cam cover. This sets the cams in the correct relationship to the crank for valve timing.
You slacken the 3 screws that lock the cam pulleys and then tension both the belts. I use the 45ˆmethod but you may use the Hz method if you are confident of the correct figure. What would be very wrong would be to use the allen key method if you slacken the 3 screws but I guess the reason is obvious.
Now you tighten the 3 screws to lock the cam pulleys and remove the locking bars.
Run the bike for 6k miles and check the belt tensions â€" if they’ve relaxed and you need to tension them you repeat the above procedure. This time, with the cams locked in correct relationship to crank and the 3 screws slackened the cam pulley will rotate as you tension the belt but the cams will not move as they’re locked. This means that the angular relationship of the grooves in the cam pulleys to the centre line of the cam lobes is different from when the belt was fitted new. If you didn’t slacken the 3 screws then the cams would rotate as well and the valve timing would be slightly retarded.
You tension the belt as before and run the bike for another 6k miles at which point it needs new belts as they’ve done 12k miles.  This time you have to repeat the same procedure of locking the cams because the angular relationship of the grooves in the cam pulleys to centre line of cam lobes was only correct for the half worn belt. If you fitted the new belt without locking the cams and slackening the 3 screws the valve timing would be slightly advanced.
If you don’t tension the belts at 6k miles then you can just fit the new belts at 12k miles without locking the cams and slackening the 3 screws.
Is the slight change in valve timing significant and do you need to bother? Perhaps not, as the facility of maintaining the designed timing was not available on the 900 and it didn’t cause a problem. It is available on the ds1000 so it’s your choice.

(Both belts are tensioned with crank at tdc comp H cyl but as the cams are locked there is no added tension resulting from the effect of the closer springs on the V cyl belt. In fact, the locking bar can onlybe fitted on the V cyl with H cyl on tdc comp - it's easier as you don't need to turn crank.)

i've checked cam timing on 4v motors with new and old belts and it's been the same, which surprised me.  that's pulled up overly tight too.

i never tension belts with the pullies locked and half screws loose.  we just do it the old way - remove belts, fit new ones and tension at tdc firing for that particular cylinder - without touching the pulley half screws..  some of the factory settings using the locking tools are fairly good, and some rather crappy in my experience.  if you want the cam timing to be right you need to check it and set it using a degree wheel, etc. 

we were doing it at a training course and the load on the pullies from the belts cocked the pulley quite a bit, to the point where the half bolts had to be overly loose to allow the pulleis to rotate as the belts came up.  then when you tightened the pulley half screws the belt tension increased due to the pulley outer moving back into true.

Quote from: EEL on October 20, 2008, 02:56:18 PM
Just use the 5mm Allen wrench trick..I don't see what the big deal is about this acoustic garbage for a 2 valver..for a 4 valver I can see that as an a possibility with is multiple cam gears..

Personally if you go by the book (i.e. the ducati owners manual), an oil change is a dealer only job.

I see a lot of comments about the '5mm allan wrench trick'   Sounds pretty good to this nooby !    But does anyone have pics of this process??
I am having difficulty in picturing the exact process. 
Where is the 5mm wrench placed ?    Is the vertical cyl set up the same as the horizontal cyl. ?  (This is all done for a 07 695)

Quote from: Ronnie-d on October 29, 2008, 02:25:01 PM
I see a lot of comments about the '5mm allan wrench trick'   Sounds pretty good to this nooby !    But does anyone have pics of this process??
I am having difficulty in picturing the exact process. 
Where is the 5mm wrench placed ?    Is the vertical cyl set up the same as the horizontal cyl. ?  (This is all done for a 07 695)

Check this out:  http://www.ca-cycleworks.com/videos/

I used the harmonic method and the allen key method recently on my '07 M695 and I think it's linked earlier in this thread.

( found it:  http://ducatimonsterforum.org/index.php?topic=11395.0 )

Still learning lots on this topic...

BK

Quote from: BK_856er on October 29, 2008, 04:30:23 PM
Check this out:  http://www.ca-cycleworks.com/videos/

I used the harmonic method and the allen key method recently on my '07 M695 and I think it's linked earlier in this thread.

( found it:  http://ducatimonsterforum.org/index.php?topic=11395.0 )

Still learning lots on this topic...

BK

Hey BK !
Thanks much for the video referance !!!   A pic, or better yet, the video, is worth a thousand words !!!!
The more I can learn about my monster, the better I feel about attempting to do these maint things.