Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 998 / 996 / 916 / 748 > Cam belts - cautionary tale

[Monty]

Originally posted by Delooney
If you dont' ride her much, instead of starting her up each weekend (now were talking rocker problems) just stick her in gear push her forward a few feet and hey presto belts in a new position and rockers saved !

Delooney

You forgot the 'take the spark plugs out' bit-have you ever TRIED to bump start a Ducati-I have and failed miserably.

John

[Nigel C]

Originally posted by Bill O
Is it generally accepted that belts are OK for 2 years or 6000 miles, or is it thought that a bike with recently changed belts but stood for a given period of time will need its belts changed, and if so what would that time period be?

2 years or 12000mls and i think that is just being safe i inspected mine when they came out after 2 years and they were like new no mishaping or chafing bike was used nearly every weekend.

when they get put away for the winter (mine wasn't ) or are stored thats when they get affected you are probably talking months for them to go like the ones in Henners pic .

I think people get paranoid after hearing scare stories about them from uninformed sources, as was said previously the belts may be cheap but fitting them ain't as not all of us are able to do it

[Jools]

Now what we all need are nice bevelled gears to run the cams from....


I'll get my coat

[BDG]

Originally posted by Jools
Now what we all need are nice bevelled gears to run the cams from....


I'll get my wooly cardigan, pipe & slippers

[Nigel C]

Originally posted by Monty

You forgot the 'take the spark plugs out' bit-have you ever TRIED to bump start a Ducati-I have and failed miserably.

John

Done it twice ! stuck it in second

got a push to get it rolling and hit the button

fired first time

[Edited on 13-6-2005 by Nigel C]

[Redsps]

cam belts, don't even go there, I cannot overstress how important it is to keep them in good steed.
A few hundred is cheap compared with thousands.

When I finally get the sps back in working order, which touch wood, will be quite soon now. It will be an area of my bike that gets maxiumum attention what ever the cost, which will be a lot less than it's costing to fix at present.

[PeteB]

Originally posted by bradders
but its not just the belts, its the £200 to fit them!

WTF??? you must be joking, who quoted that then??? must be ohhhh £100.00++/hour labour charges, robin bastars

In my humble opinion belts don't just break IF there is no aditional loading on them other than in tolerance valve operation.

If/when they break its not old age but more likely seized idler/tensioner bearings, tight closer clearance, poor adjustment, loose pulleys etc etc.

[aka.eric]

Originally posted by PeteB

WTF??? you must be joking, who quoted that then??? must be ohhhh £100.00++/hour labour charges, robin bastars

In my humble opinion belts don't just break IF there is no aditional loading on them other than in tolerance valve operation.

If/when they break its not old age but more likely seized idler/tensioner bearings, tight closer clearance, poor adjustment, loose pulleys etc etc.

Or P--S Poor quality control in Ducati case,but agree totally age is not a factor.

[breakout]

I have noticed that some belt failures are the obvious result of the fitting of pretty aftermarket pulleys.The problem is how the belts fit to the pulleys,they should not contact the belt across the tops of their teeth when they do this, I have noticed after failure, the tops of the sprocket teeth are abraided (damaged) this is symptomatic of the damage done too their adjacent running surface,-which is the kevlar belting at the bottom of the belts grooves.This belting transmits the power to turn the cams and obviously mechanical damage to this structure is to be avoided.Also as the volume of the female sprocket groves is greater than the volume of the male drive teeth on the belt, the teeth on the belt are not under compression and are much more able to be pushed over;-this cyclic plastic deformation is larger than would otherwise occur and will lead to premature failure.I believe a new belt should not contact the pulley across the tips of the pulley teeth but rather should be located radially by the belt teeth sitting in the sprocket grooves and there should be clearance across the tops of the teeth.belts also fail as tyres do as a result of total heat cycles(note 999r and the race bikes have ventilated belt covers to lessen the serverity of the heat cycles,and the belt need not perform any additional 'worthless ' work like trying to turn a damaged valve train ,obviously belt tension is critical and tricks and rules of thumb shouldnt be employed unless you know what you are doing and are prepared to handle the outcomes,anything which changes the belt friction (silicon sprays etc should be avoided.Lastly SOME BELTS ARE BAD BELTS, and if you are rude to your bike it may be rude to you ;-always wash and service your bike,whilst talking nicely to it.breakout