S2r 800 timing belt melting/shredding

[ANedelka]

Went for a run to the store last night and 1/3 of the way there I could here an odd clanking sound. I pulled over and pulled my flashlight from under my seat to take a look. I found some black woven material wrapped into the pulleys of the horizontal belt. Nothing at all on the vertical belt. I'm assuming the clanking was the cylinder no longer in proper timing.

First some details on my bike:
S2r 800
Recently adjusted valves
Bought from ca cyclewerks
Belts are 1 year and at most 5k miles old
I run with the belts open

So my questions are:
How can I determine the level of damage to the cylinder?
What could have caused the belt to suddenly come apart like that?
What needs to be done to fix it?

Thanks for any help you can provide
-Andrew

[Raux]

running open belts
could have been a rock

or with recent valve adjustment
could have been belt tension

and likely you have damaged valves

[He Man]

you purchased the bike from ca-cycleworks or do you mean you bought their belts.

who did the vakve adjustment?

pictures would help.

belts dont just come apart like that. Ive ran 3 pairs of exact fits and they wouldnt shred like that unless you jammed something in there (a member by the name magnus had the same thing happen to him, just threads everywhere)

If you run open belts its always a danger but you are the first ive heard of having this problem on a 2v!

sounds like you bent both valves on the foward cylinder.
youll need to check the valve stem for openign and clsoing clearance, you can also do a leak down test on the foward cylinder, or a compresion test, bent valves wont have a good seal. lastly you can just pull the head.

[Slide Panda]

Running open belts exposes them to more weather and more importantly debris. All kinds of shit gets kicked up from the roads. Rocks, bolts, ask IZ about screws... A sudden failure like that is probably due to damage from an external input - aka something hit it or got sucked in.

Also with exposed belts, you're exposing the tensioner bearings to weather. So it's possible that a bearing or two in the tensioner 'system' has bound up or is binding and causing friction

To be sure about damage, 100% sure you need to have the head off. A less invasive check would be to pull the belt, and manually turn the engine to drop the piston. With the belt off and the piston out of the way you can hand turn the cam. The action should be smooth with an increase in torque needed to turn it as you come up against the helper spring, with it then spinning a touch on it's own as it goes over the nose with the spring pressing the rocker on the lobe. If you feel binding, grinding etc - that's not good.

You should have the inspection covers off while doing this also so you can see the action of the valve stems.

[ducpainter]

The melting could also indicate a seized tensioner/idler pulley bearing.

[Speeddog]

The melting could also indicate a seized tensioner/idler pulley bearing.

+1, most likely cause.

[ANedelka]

I can get pictures to you guys later tonight when I get home. The belts were from ca cyclewerks, not the bike. Ok so I'll try and pull the belts tonight and see how it feels in regards to the cam. How could I go about checking if those tensioners are frozen/unstick them? Thanks so much for your help already guys!

[Slide Panda]

How could I go about checking if those tensioners are frozen/unstick them?

They are jsut sets of ball bearings. They should turn easily and smoothly. If it takes more than a tiny bit of force to turn one or there's a crunchy feeling like sand's in there those are likely signs they are failing/failed. Obviously if they don't turn at all... then it'd dead

[ducpainter]

I can get pictures to you guys later tonight when I get home. The belts were from ca cyclewerks, not the bike. Ok so I'll try and pull the belts tonight and see how it feels in regards to the cam. How could I go about checking if those tensioners are frozen/unstick them? Thanks so much for your help already guys!

You can't 'unstick' them.

Like SP says, if they have any grittiness at all they're done.

You might be able to find replacement needle roller assys at a bearing house, or from Ducati.

[ANedelka]

Ok perfect, I'll check that tonight! Would anyone be willing to ballpark a cost on repair for this?

[ducpainter]

Ok perfect, I'll check that tonight! Would anyone be willing to ballpark a cost on repair for this?

Not until you pull the head to see if the guides or head are cracked, guides probably are, and whether the piston is damaged.

[Slide Panda]

Impossible at this point. It'll vary wildly depending on what is found. Could be lucky at it'll be a new belt for about $40. The mobile tensioner is $72, the fixed one is $54
But if you've bent a valve or have other damage the price is going to go up quite a bit.



You can look up the parts cost:
http://www.ducatiomaha.com/products.asp

[ANedelka]

Ok well I'll pull everything apart this evening. How does the head come off? Just those bolts at each corner or is there more?

[ducpainter]

Remove the carb, the belt, and those 4 nuts and it should come right off.

If it's the horizontal there is a sensor in the valve cover to disconnect also.

[ANedelka]

Carb? I thought the s2r was injected, or does carb mean something else? Also, a stupid question but I assume both belts need to come off? once the head is off what should I be looking for? You guys have been awesome with your help, thanks so much