TIMING BELT FAILURE

[dragonworld.]

Might be worth a mention here regarding the Ducati cheap arse bearing thing!? And a potential for belt failure possibly?!  

When doing a service belt change on the old 7fiddy I checked the cam belt roller bearings and they felt a tad tight in rotation! So being 80,000k old I thought I'd change them and removed them and went down to the local bearing place and got a set of replacements.  

The fella said they were rated to 15,000 rpm so were ok for this application. After finding the shitty bearings on the DS I checked the bearings on the 750 (Including the cam rollers as a matter of course.) after getting a heads up regarding sub standard name brand types, and found that the "new" cam roller ones had gone a little notchy after only 2,500K!  

And yep they were the cheap arse made in China replicas of SKF.  

Just an observation for the interested!  

[krista]

A friend of mine recently had his ducati rebuilt and a new exactfit timing belt fitted. Less than 500kms later bike seizes and mechanic who fixed the bike said the belt had failed and all the notches were stripped off. Would this be covered by some kind of warranty from belt manufacturer?

Whoa! I'm actually surprised we haven't been included in discussion. Technically, to rip teeth off requires the sprocket to stop first... In continuing to read this thread, I am having my doubts about the situation in its entirety. I absolutely stand behind my belts but I'm not going to be able to do anything if the situation has already been repaired and no one is willing to talk about it. 

Ok the issues I had were the belts would get extremely noisy after about 5 mins of riding - to me it sounded like a bearing failure.

"Bearing failing noise" is exactly what happens when the sprockets and belts need to be broken in. Our belt manufacturer says standard practice is to replace the sprockets with belts concurrently. Obviously, this practice is never adhered to with Ducatis, so isn't a requirement for safety / longevity. Also as Ducati OEM belts lack the protective rubber coating on the teeth, theirs will squeal less than ours will during break-in. Unfortunately, when I had our belts designed, I asked for the best of industry practices to be applied with all aspects and that no corner-cutting be allowed. Thus our belts have the protective rubber coating on the teeth. I chose not to try and figure out which cost-cutting measures Gates and Ducati have applied to the OEM belts. My choice was to have the best belt that can currently be manufactured.

Also, about the belts tightening up when the engine is hot. Belts don't stretch... even after 20,000 miles, we have had belts tested to be within the same .002" tolerance all of our belts meet upon manufacture. As the engine heats up, the heads move away from the drive sprocket, which increases tension. This doesn't cause the noise. The squealing is caused by the teeth slipping as they slot into the sprocket. Within a 1000 miles, the rubber belt will have worn away enough steel from the sprockets that the noise stops. Yes, it sounds backwards, but is correct, the belt wears down the steel sprocket.

There have now been 3 cases where a 1000-type of engine has done this. 2 have been issued apologies with refunds. 3rd just rode his bike and it got quieter until the sound went away. It is my feeling that in this rare and unfortunate case, the best thing is for the customer to do whatever feels the best. Which means trying new OEM belts to see if they are quiet. As our belts' length varies by 1/2 as much as Gates, there is every likelihood they had one that was farther from the norm than ours. Then the new OEM belt without its rubber coating can break in the sprockets more quietly than our belts. Additionally, some service technicians I have talked to said they see OEM belts doing the same thing.

I feel for macca's friend and hope for the chance to learn or help as much as possible.
-Chris

[dragonworld.]

The CA Belts I fitted to the 750 whistled for a while (1k to 2k) and seemed to be less noisy after that, but still a little "whiny" when compared to the Bucci or OEM's?! 

As is usual when I have used a new component I have checked the belts and pulleys regularly since fitting and there seems to be no sign of anything nasty happening!!

Thanks for the input Chris, and would be glad to hear of any developements from your side!!

I think its a good idea to check rotational friction and endplay of the cams when fitting new belts as a matter of course!? Just in case of course! ( For the paranoid of us!?  )

[Mr.S2R]

"Bearing failing noise" is exactly what happens when the sprockets and belts need to be broken in. Our belt manufacturer says standard practice is to replace the sprockets with belts concurrently.

I was never told about the sprockets. Very interesting!

When the OEM belts need replacing I will try the CA belts (with new sprockets) again, entirely due to Chris taking the time to deal with a customer - which I believe he has gone out of his way.  I hope you don't interpret anything I have said as negative about your belts Chris.  I attempted to keep my experience to facts and what I was advised.  I just put it down to me being that small percentage (aka just my luck  ) of people that get the odd anomaly from what is usually a great product (probably backed up by heaps of others on here!!)

As a side note the whole belt thing absolutely fascinating - only because when I owned my 650 Pantah I was never told to replace them in the 5 years and 30,000km of owning it! AND I had it serviced by a reputable place!

cheers
Jason 

[dragonworld.]

Yeah Jase

The inclusion of the HD is a mystery as they use a truck battery(?) and would need the appropriate charger (Larger diesel plant equipment type as for mining tip truck or ocean liner?  )

And I reckon the classic parked in the water was so the photographer could get the lovely rainbow effect of the oil floating on the water in the subtle fading light? 

[matt.e]

Hi everybody my name is Matt and it is my bike that the topic is about. Macca is a mate of mine and seeing my woes decided to help me any way he could. I decided to join the forum to get a few things straight and to give the actual run down of events. No one is playing the blame game with the products nor with the mechanic. I will say though at the end of the day I am left nearly $4000 down through parts and labour and a bike that worked for a week. So ask yourself honestly, if this was happening to you would you want answers or more?

(Sorry Chris, I had discussed with the mechanic on 9th April that he would contact the rep in Aus but realised on Friday that he hasn't been contacted.)

HOW IT GOES- Sorry guys but my bike isn't a Monster but is a 748/853 and cammed up. A cam belt pulley come away making the belt snap go through everything, bend up valves etc etc. I got all the parts from the U.S which were all OEM parts except the belts. Intake/exhaust valves, valve guides, half rings, pulleys and pulley guides. I got the bike back and sounded and ran beautifully(very hard bike to tune). A couple of days later I started to hear a slight kind of quiet whirring noise. I don't recall if it was all the time or intermediate. On the last day it became louder and I decided to ring the next day but crack and the back wheel locks up. I only could move it with clutch in.

The bike went back to the shop and and on inspection the belt had snapped causing a mess and bending some of the valves. Before anyone says it, no it's not a recurring problem because the first time it was the pulley that come away causing the belt to make a mess but this time all pulleys were intact and spun freely(except the one with the damaged valves.) The belt still had it's teeth barr the ends of the belt that were now stretched, a little melted and a mangled mess. In some areas the back of the belt only held the teeth on by this fabric looking material and no actual rubber belt was there.

The bike has quite a few k's for a Ducati and gets ridden most days. I have a lot of people through the years say it's getting on now etc but I have ALWAYS maintained or replaced parts as soon as it is "needed" or brought to my attention. I've had the bike since 2002 and have spent now to date about $28000.00 maintaining or replacing parts for it. So for the riding it gets it's fair to say I pay for it to do that. If we didn't love our pride and joys we wouldn't see Hailwood or green frames etc anymore. Yes up close the cosmetics aren't great but a book shouldn't be judged.......

The mechanic told me the parts that I need and has offered them at cost price however I just can not do it so soon or maybe ever again. As I have already said I nor no one else is pointing fingers and this could be in any state. I would have no hesitation in taking future bikes to my mechanic and his work is always meticulous. Yep I am very confused about my situation and don't know what is right or wrong. Sorry to go on but I wanted to straighten everything out.

Regards
Matt

[Betty]

matt.e thanks for coming on and letting us know. I appreciate the fact that names and locations have not been mentioned ... other than, unfortunately, the belts themselves.

I am a complete mechanical dunce so excuse me if I have mis-interpreted something, but my understanding is:
. re-build was required after a cam belt pulley came away causing plenty of damage
. so then came the re-build
. after the re-build the engine has unfortunately suffered a similar fate with a snapped belt the suggested cause

Clearly I don't know what I am talking about but if the valves, pulleys and belts are all linked ... how do you know what caused the failure? For example, could the belt have snapped as a result of something else failing first (I am assuming the flow on effects would be instantaneous).

Does the condition of the belt indicate that it was, in fact, the belt that went first? That is, if the belt snapped would you expect for it to appear stretched and melted?

Anyway, really sorry to hear what has happened.

[Raux]

so the rubber on the back side of the belt was worn off? sounds like either the belt was mounted too tight and/or a failure of the tension pulley.

[matt.e]

Hi Betty,

Can't be too sure what caused it to happen but all those things had been replaced in the build. Usually when a belt goes from wear or age the outcome is what I have now. That's one of the reason on a big service the belts always get changed so you don't end up with an expensive mess. The whole saga had left me deflated and over it but then something happened last week that kind of got my back up and left me thinking "hang on I am the one out of pocket 4k and a non working bike with no answers".

Hi Raux
It would be the easiest solution to say that the belts were to tight or loose when installed but I think it's fair to say that this guy could do it in his sleep. The tension pulleys were replaced as well

It's just a shame that I have to give up my pride and joy through no fault of mine. I'm now riding a 82 1100 Katana and before now I hadn't owned a japper since I was 19, I am now a year off 40. I miss the duke because I haven't "really" had it since Sept last year.

[loony888]

have the tensioner and idler pulley bearings been checked?

[matt.e]

have the tensioner and idler pulley bearings been checked?

They were replaced but I'd still like to think that the replacements were checked for free spin etc.

[FIFO]

Hi Matte

Not much joy when your left holding the can.
You say you had cams done.
You don't say how many klms after when the timing belt pulley has come away.
These thing's just don't come away.
Unless the has been an assembly issue, crappy nut or theads etc.
And now rebuilt, buy who the same mechanic?.
And week later it shits itself again
Alarm Bells ringing hello
You say the mechanic can do it in his sleep.
I am no mechanic, but have over 35 years in manufacturing and machine maintenance.
And shit happens buy the best of us and the worst off us, you know the saying she will be right mate .
I am not ruling out any thing, as no pictures and only what the mechanic has told you.
And i am  not about to name and shame or ruin some ones lively hood. you just need it fixed

I'm with Chris on the belts something has had to stop/ seize for the belt to fail.I just installed a set on  mates bike no issue and they look very well made.

I would be getting the bike back and get  an independent  mechanic look at it.

And now if it's allready been stripped buy said mechanic, easy to replace the faulty part with a good one to cover your self ,to an unsuspecting customer. seen it all before don't trust anyone.

matt.e thanks for coming on and letting us know. I appreciate the fact that names and locations have not been mentioned ... other than, unfortunately, the belts themselves.

I am a complete mechanical dunce

Oh and don't belive Betty he or is that she knows more than than he or she is letting on

[matt.e]

Hi Rob,

HaHa yeah I thought the same when I read Betty's post. There is definitely some kind of mechanical mind behind those questions.

Nah just before the pulley came off I had some internal work done by another group and I think they might have been the problem. Before I had even said anything they were already covering their backsides so I knew there was going to be no point unless taking them to small claims. By this time I was on the road to giving up spending anymore money on it and my heart was so low. The bike was going to become a garage piece. I then got on the net and realised that parts are so very much cheaper from the States so I got them all over then took them to this mechanic. I also did my research on the belts and found nothing but good comments so I got them as well. When he got it the bike had already been pulled down and it was explained to him what had happened. I trust that Barry had the correct tension on the belts. I know he understands my bike if that makes sense. Tuning the bike has to mainly done by ear and forget the computer. Alot of places I have taken the bike just can't tune it for the street...

I understand that something would have to stop for the belt to stop but the only thing that could move afterwards was the intake pulley and that was because the valves were bent. As mentioned before there was this whirring noise that got louder and louder then crack! I also had both belts replaced and the other is fine.

The cams are lumpy cams but they have always been in it since I got it and with no problems(except when it needs a tune)

These are the factors to do with the bike---  The Bike, Belts, valves & pulleys, Mechanic, me.  Well I guess I can be pulled from this equation and the bike because the parts to do with the problem were all replaced(Maybe a slight chance something else was missed or not checked). So just going on the facts and not being offensive, there are only a couple of things left in this equation.

[matt.e]

Okay cam has a slight bend in it Yay!!! That would of caused the belt to run weird on the pulley. If I decide to keep it, I'll get the parts and i'll get them fitted for free. The offer was given from him to pay for the whole lot but that isn't fair on him. I would only do that if it was from direct fault of that persons actions etc. I have confidence in this mechanic and he came through in everyway. I got an answer what caused and it makes perfect sense. Thanks everyone with your suggestions on what it could be or to look for but most of all thanks to..................for the real old fashioned service.

[mattyvas]

Hey Matt,

It's great that you have an answer then instead of a bunch of questions still.
Your bike sounds like it has even more nuances than most Ducati's already do.

So it's also nice to know that it want a belt failure and particularly a CA belt failure as there are many of us who use the products and have never had any issues.
I am sure Chris will also be happy to know that his product was not at fault.

Hope you get it fixed shortly so you can get of that classic Katana so it can become the piece in the shed and your bike can once again be where it belongs which is out on the road.

Happy riding when you get back on the road with great CA belts installed..
Have no fear Chris your products reputation is still intact.