[RoyMcNally]

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Sorry about this, you've all probably seen this kind of thing a thnousand times before, but I'm really confussed about the correct way to measure tensing in a 748 timing belt.
My bike is a 1997 748 Bip, and the advice I've generally seen is on measuring deflection (5mm) in the top run of the belt, or use the Ducati service tool (how do you get hold of one of them?). The other way I undestand it can be done is is using an acoustic system - i.e. a guitar tuner?
Now what I want to know is can I use the acoustic method on a 1997 model as the threads I've read seem to suggest it's only really for the later 749 models?
Any help would be great.

Thanks

[Spudd]

I would go with the deflection or tension of the belt. Essentially, you want to take the slack out of the belt, but don't over tighten it or stretch it.

[brettc63]

Originally Posted by RoyMcNally

...........
Now what I want to know is can I use the acoustic method on a 1997 model as the threads I've read seem to suggest it's only really for the later 749 models?
Any help would be great.

Thanks

Yes. The acoustic or harmonic method can be used on just about any belt in any situation. They use it in a lot of industrial and automotive applications. Any Ducati with belt drive cams.

[yellow blur]

Also - make sure you rotate the adjuster counterclockwise when setting the tension or the inside of the belts can rub together and also walk to the edge of the pulley which will cause fraying the edges of the belts and tearing them up.

[RoyMcNally]

Thanks very much for your help

[DukeDesmo]

The Facom gauge works well and is easy to use;
Facom Timing Belt Tension Gauge DM.16 | eBay

[pat1098]

Ducati's method for adjusting the cambelts has altered over the years, from a physical distortion measure, to an acoustic reading.
The acoustic method can still be applied to your model. You need to check the standard recommended settings (in Hz). They used to be 75 and 85 - different for each head - on the earlier 8-valve, where the current series recommends 110 Hz. Personally I think 100 Hz is tight enough - you still need to re-check them after a time.
I have had trouble getting a meaningful reading out of two different (downloaded) acoustic frequency meters, and am still setting them the old way, by feel. But I have been replacing Ducati cambelts for 30 years..
Be aware that you need to find Top Dead Centre on the compression stroke to set the tension correctly.
The most important thing is to re-check them after a couple of thousand kms if you've fitted new belts, as they do stretch initially.

[ducatime]

for what it's worth, I checked the various ways to adjust the 996 belts and finally used the deflection mode. i.e I used a vernier caliper placed on the engine cam housing and measured the upward / downward deflection using moderate pressure.
Now 'moderate' may mean different things to different folks, but basically, enough pressure that you might use with the forefinger, before you feel discomfort... again.. open to interpretation, but you get it.

5mm for the front belt.... 6mm for the rear belt.

BUT! It really does pay to recheck within a thousand or so kay's as suggested by pat.

Better a 'little' loose

[Ian998]

Try this site

916 Belt Change

Ian

[RoyMcNally]

Originally Posted by Ian998

Try this site

916 Belt Change

Ian

Thanks very much for this Ian. I think this is the best photo guide I've seen. Much better than the Haynes manual.
cheers