Following on from this:- https://www.ducatiforum.co.uk/threads/that-didnt-go-well.92264/ I thought I'd start a thread here to cove the project of sorting out the engine in the bike. Initial inspection without touching anything shows that there is definitely something going on behind the belt cover. Not only is it cracked, but there appears to be a whole load of fibres and dust everywhere that wasn't there before. Having never seen a snapped Ducati belt before, I don't really know what I thought I might see, I knew the belt might be shredded, but I wasn't prepared for what looks like the belt exploded in a spectacular way. And this is what I recovered:
And so on to the assessment after cleaning out the worst of it: Firstly, both the fixed rollers and tensioner rollers are as free to move as the day I put them in, so a seized roller is not the cause of the problem. Of course they will all be changed again when(possibly if) the engine goes back together. With the Horizontal piston at BDC to make room for the valves the cam appears to spin over freely enough, with equal resistance to moving the Inlet and Exhaust Valves. With the inspection covers off everything appears to move OK, and nothing appears amiss at all. But, on putting my small Bluetooth Endoscope down the bore there is a definite witness mark where the Exhaust valve has touched the piston in the the pocket machined into the piston crown for valve clearance. Bugger. Still feeling lucky I decided to try a compression test using an old set of belts. I'm not sure if they came out of this bike or my M1000DS, but they are perfect to do a compression test without buying a new set of belts. Unfortunately there is ZERO Compression on the Horizontal Cylinder, compared to a healthy 110psi on the vertical Cylinder. Being hopeful, it could just be a bent valve, the image from the Endoscope doesn't appear to show any real damage to the top of the piston. I've soaked the Head nuts, exhaust stud nuts, and those that hold the inlet manifold to the head, in a mixture of Diesel and Acetone, which I'll redo everyday over a few days, then the full extent of the damage will be known when I can get the head off. I have my M1000 on my lift bench at the moment, and need to finish a couple of jobs on that before being able to get the 1000SS on the lift to make working on it more comfortable. Replacement Exhaust valve? Replacement head? Worse? Who knows. Watch this space, but don't hold your breath.
With a bit of luck the valves will have 'snapped' shut when the belt snapped and only the piston only kissed the exhaust valve. You might get away with a new valve and possibly the guide. That's what happened on my 851 when it broke a belt.
Fingers crossed for reasonably good result for you, I learnt something new and did a double take i never knew the plugs were in that position.
They are twin plug heads, DS, Duel Spark, so there is a plug either side. Yep, that's what's bothering me. I'm 100% sure I didn't over tension it, and the rollers are all fine. Could of course be the Genuine belts I purchased online, perhaps they were old stock or hadn't been stored correctly. I'm worried I'll never really know.
Good luck. As you've been so good with the refund, I'll happily send you £20 to a "go fund me" to help with the costs. I'm sure others on here would do too.
Wow Cream Revenge, that's a really nice thing to offer, very much appreciated, and possibly the nicest thing anyone has offered to do for me in a very, very long time. Thankfully I can cover it from my project pot, and actually may already have a lot of the parts it may require in stock already. I didn't really want to sell the bike, and only did to make room and create funds for another project. I'm making myself feel positive about the whole thing by saying I get to keep the bike a while longer, will ride it a bit when it's fixed, and have the project I was looking for, although possibly not on as large a scale as I wanted. I've also brought some time to look at options for making space for an extra bike and may not have to sell it again when it's fixed.
Good attitude Nasher! BTW if you get rid of the sofa and put the TV in the kitchen, the lounge could resolve your problems?
Same here & I also learnt that a mixture of torx & allen headed bolts are used. Presumably for the convenience of the home mechanic...
The belt seems to have been sliced in half ......half of its width....as if it's run off the bottom pulley ....and the metal end has sliced it ..... The big question ...what caused it .. ? .. are all the pulleys aligned.....foreign object in the belt covers ....is the engine as it was originally run ? ....or have parts been swapped between engine types ... Anyhoo ......good luck with this nasher ....hope you get to the bottom of it. I wonder if Rich at Louigi Moto could give you any ideas ...?..... Or Ducati John maybe ....
I think @Gerr has a point, perhaps rather than the belt overextending with expansion of the cylinder perhaps it somehow came loose and slipped off a pully thus rubbed against the sharp(er) edge of said pully. Just a suggestion
Your picture showing the remaining belt carcass with a longish slit down it is the most revealing for me, and presuming the belts were fitted as a pair, a study of the "intact" other belt* would be of great interest for me. Would be good to know manufacturer and date of belt, but latter probably difficult Simon? also when/how long fitted and approx miles although I think you covered this in the other thread. I can't remember which day the bike got ridden to Reading but further to p.m. to you, constant, extensive engine tick-over between hard use is the only other factor I can think of at the moment that might be a factor here on a "healthy-sh" belt. As said, only a guess as no piston crown picture, but looks like apart from belts, a valve, a guide and a re-seat is all you will need here. *a miracle that he got home in that set of conditions.
oh Simon, that's a bugger! hopefully minimal damage is found, knowing your attention to detail and skill I'd suggest counterfeit belt(s)! Best of luck with it.
Chris The Belts were Genuine Ducati belts purchased online early last year from one of the well known Ducati independents along with new Tensioner and fixed Rollers. The Rollers came from Stein-Dinse, but I can't remember who the Belts came from, it was an independent, not Moto-Rapido. I must dig back through my emails. They were the first set of Genuine belts I've brought in a while, preferring to use the Exact-fit belts normally, but I think these were on special offer. Perhaps they were old-stock? The remaining vertical cylinder belt is really badly damaged, but when I get it off I might be able to see the manufacturing date. Note Exact-fit specify a lower tension than Ducati, but I would have used the Ducati figure. I use the JPDiag Belt Tension frequency measurement with a small microphone on my laptop, not a phone app. Sadly the bike had done less than @500miles since. It was collected on Friday the 15th July, and I think Temps were late 20s early 30s. It was ridden from my place near Petersfield to just West of Henley-on-Thames, but the gent who brought it was enjoying the bike and went the long way home, I believe completing @100 miles before the bike went on to 1cyl @ 5 miles from his home. From the discussion he and I had on the phone the bike had got far hotter than I had ever run it at. 20mins after turning it off the indicated temp on the instrument cluster was still 114deg, I'd never seen higher than 110deg when I'd ridden the bike. Remember that's indicated temp not actual, we all know Ducati Temp gauges are used for comparison not actual temp NOTE:- I do obviously understand there is the chance I cocked this up and put too much tension on that belt. I will never know. Although I wasn't expecting the amount of disintegration to the belt(possibly as pointed out by somebody down to the 5mile limp home) I'm not surprised at all by the split down the middle nature of some of the remnants. I've never had a car or Ducati belt go in the past personally, but have seen several car and machinery drive belts post snapping. All the strength is built into the belt longitudinally, with internal stringing in that direction, there is little need to build much strength in widthways. So when the belt starts to go, it will easily open up like a zipper along the belt. Compare it to how easy it is to rip a piece of some cloth in one direction but not the other. I'll get an image of the inside of the belt covers. There is obvious damage where there was a build up of loose belt around the centre pulley, but no evidence along the cylinder that the belt had moved sideways.
