Facom/Snap on belt tension tool
 

I've just bought one of the £50 Facom DM.16 belt tensioner tools off eBay. I assume that we should be using the 5mm thickness cap as the belt fits nicely in the "5"mm slot in the plastic gauge (even though the actual thickness is 5.5mm). I've just done a quick check on the belt tension on the 888 (which I recently set using the "5mm deflection between the cam pulleys with moderate thumb pressure" technique). I got a reading that was just a little less than the upper groove (setting 'A' for new belts). When I set the belt tension so that it exactly matched the upper groove in the gauge, the tension felt a little too tight to me. Can I check if others are setting belt tension exactly as per the instructions and if anyone has checked what the tool reads on belts that have been previously set with the Ducati tool?

Keith

MMMmmm, i'd be interested in the answers to this as i am contemplating getting one, to do my belts.

The "recommended" button isn't the right one. I can't recall exactly but I think you need to use the no. 4 one.
No reason why, it's just the way it has to be. I think it may be down to the short belt run you are measuring between the pulleys.
I'm sure the info is on the site somewhere.

Jasper set his T8s belts at the weekend using the number 4 button. He was going to get Ducati John to check the tension to confirm and then post on the site if there was a problem...

Yep on my Snap-on tool you get the wrong belt tension if you use the recommended button, I have always used the No.4 Button and when I mentioned this to Nelly a couple of years ago he said he was also using the 4 button.

Thanks guys! I tried retensioning with the number 4 button and that made the belt even tighter! I guess the problem with the "5mm deflection between the cam pulleys with moderate thumb pressure" technique is that one persons definition of moderate pressure can be quite different to anothers.

Keith