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Discussion Starter #1
01 750 Sport 4,500 miles...
Salvage bike that's been sitting for 7 years in storage. Took the covers off to replace the belts and saw what is in the attached pic. Not knowing Ducs and not wanting to do a belt install removal install repeated cycle has anyone seen this problem where the H belt wants to ride 1/4 off the pulley? Can this be a function of the belt being too loose or could be be some other problem? It has been going on for some time judging by the rubber built up in there and it cut all the way through the plastic cover.
 

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I'm thinking belt too loose, but also check your tensioner pulley I bet it's seized.


01 750 Sport 4,500 miles...
Salvage bike that's been sitting for 7 years in storage. Took the covers off to replace the belts and saw what is in the attached pic. Not knowing Ducs and not wanting to do a belt install removal install repeated cycle has anyone seen this problem where the H belt wants to ride 1/4 off the pulley? Can this be a function of the belt being too loose or could be be some other problem? It has been going on for some time judging by the rubber built up in there and it cut all the way through the plastic cover.
 

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Pull the rest of the H cover off and post a few more pictures so we can see what's what in there. I'm betting on a seized idler or tensioner pulley, but I wouldn't bet much on that without more info.
 

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I'm thinking belt too loose, but also check your tensioner pulley I bet it's seized.
:) Don't take to much for things to go bad with belts!
 

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Could also be the drive pulley is loose on the jackshaft. Or the shaft bearings bad. Pull the upper cover and see if the vert. belt is running off too. Most likely the tensioner/idler but I've seen the jackshaft bearings go bad before.
 

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Discussion Starter #7
More pics

Someone mentioned the V belt I think it is OK IIRC.
Can't see the top pulley in any of these... Bike is not where I live so I'll check out the tensioner(s) and idlers. The black crap is belt rubber. Hard to believe that much would go bad with 4.5k on it.
 

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I had a nut on a cam pulley loosen on me that made a mess like that. I'd say pull the belts and see. You're going to need the tool to hold the pulley and the socket to tighten the nut. They are supposed to be 70-75 NM. Bearings are a possibility, but for a belt to want to walk off center like that, something has to be out of alignment. That shredded rubber you see in there is not normal, and indicates the belt has been rubbing on something, likely the inside of the belt cover. I wouldn't run it like that, a belt coming off is bad news on these engines.

Edit:
On closer inspection of the pics, I see the teeth on the outer edge of the belt have been eaten away by the drive pulley guide. This needs to be addressed before the bike is run again. My bet is that horizontal cylinder cam pulley nut. You may think that if it loosens, the pully would just slide in and out on the cam’s axis. You may find, however, (as I did) the cam’s shaft is not perfectly squared off and when the nut loosens, the pulley can be pulled off axis by the belts tension. Left loose long enough, things get much worse.

Here's how bad mine got before I noticed it after a 50 mile ride into work. To say I was lucky the belt didn’t let go is an understatement. When I pulled the belt, the pulley in the pic was loose on the shaft. I replaced the very worn key way, the big washer, the ring nut, belts and all was well.
 

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Sorry about this being off topic, but

What are the coin-size round black bits wedged between the cooling fins of the vertical cylinder in the pic?

I found them on my superlight, took them off (they are just small pucks made of plastic) and could not figure out their purpose.



 

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Sorry about this being off topic, but

What are the coin-size round black bits wedged between the cooling fins of the vertical cylinder in the pic?

I found them on my superlight, took them off (they are just small pucks made of plastic) and could not figure out their purpose.



They are anti-vibration bungs to stop the fins buzzing around. :)
 

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Wiggledbits - has somebody had the cam pulley wheel off the h.pot and put it back on the wrong way/used a different cam pulley wheel?

(Not sure if there is a wrong way tbh? Would this give the offset shown?)
 

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Has this got the right belt covers on it? It has 900SS covers on it, I thought the 750 ones didnt have the inspection windows?
 

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Discussion Starter #13
I had a nut on a cam pulley loosen on me that made a mess like that. I'd say pull the belts and see. You're going to need the tool to hold the pulley and the socket to tighten the nut. They are supposed to be 70-75 NM. Bearings are a possibility, but for a belt to want to walk off center like that, something has to be out of alignment. That shredded rubber you see in there is not normal, and indicates the belt has been rubbing on something, likely the inside of the belt cover. I wouldn't run it like that, a belt coming off is bad news on these engines.

Edit:
On closer inspection of the pics, I see the teeth on the outer edge of the belt have been eaten away by the drive pulley guide. This needs to be addressed before the bike is run again. My bet is that horizontal cylinder cam pulley nut. You may think that if it loosens, the pully would just slide in and out on the cam’s axis. You may find, however, (as I did) the cam’s shaft is not perfectly squared off and when the nut loosens, the pulley can be pulled off axis by the belts tension. Left loose long enough, things get much worse.

Here's how bad mine got before I noticed it after a 50 mile ride into work. To say I was lucky the belt didn’t let go is an understatement. When I pulled the belt, the pulley in the pic was loose on the shaft. I replaced the very worn key way, the big washer, the ring nut, belts and all was well.
Yours is much worse...
I'm in the process of getting this 750 back on the road and once I saw this I knew the belt wondering had to be fixed. I was thinking the H cover had done the damage but maybe not. Leads on these tools?
 

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Discussion Starter #14
Wiggledbits - has somebody had the cam pulley wheel off the h.pot and put it back on the wrong way/used a different cam pulley wheel?

(Not sure if there is a wrong way tbh? Would this give the offset shown?)
I can't answer any of this because I have no history on the bike. It was salvaged from getting rear ended. I was thinking a $800 price tag on an 01 Ducati 750 Sport with exactly 4,320 miles was a good deal but maybe not now ... :abduct:
 

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Leads on these tools?
Tool Product Gallery

Row 8 and 9. Pricey, but after my close call, I now hit them each valve check. A lot cheaper than a belt break! They are available in a few places if you search around.

Before spending on the tools, you may just want to pull the belt to see if you can wiggle that pulley.
 

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I can't answer any of this because I have no history on the bike. It was salvaged from getting rear ended. I was thinking a $800 price tag on an 01 Ducati 750 Sport with exactly 4,320 miles was a good deal but maybe not now ... :abduct:
No your o.k. easy fix thats what great about these bike you can do most of the work yourself! When a bike sits out for a long time (2V) you should always replace the belts and do a once over like clean and lube, fluids(all) then turn the key!

Belts are like tires they get old and crack and the weather don't help much, I change my belts 8,000 or 2 yrs but always check them and at the Track its a must to keep one eye on them at all times. Not very pretty when a belt breaks at 8,000 rpm my wallet knows first hand!
 

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Discussion Starter #18 (Edited)
No your o.k. easy fix thats what great about these bike you can do most of the work yourself! When a bike sits out for a long time (2V) you should always replace the bikes and do a once over like clean and lube, fluids(all) then turn the key!

Belts are like tires they get old and crack and the weather don't help much, I change my belts 8,000 or 2 yrs but always check them and at the Track its a must to keep one eye on them at all times. Not very pretty when a belt breaks at 8,000 rpm my wallet knows first hand!
Yep, been going through it all as I replace parts. I have the belts and dot fluid flush yet to do. Then put it all back together, get registered and tires on her. I have spent more money than expected as expected but then I have replaced some stuff that I didn't have to like the seat, left hand mirror, maybe the C & FB masters and a few other things. So far I have done the exhaust header to cans cuz that is where it got hit, swingarm cuz it got scratched and dented, fuel pump cuz it stopped working, all the plastic and grab rail, levers, front axle, chain, fuel filter and all fuel lines, oil and filter will again after a few miles. I still need to get the oil cooler bracket right mount tab brazed or welded back together, left faring mounting tab straitened and the right passenger peg mount bent back to normal. She starts up great and sounds good and strong. My only concern is a metal ping type sound from the H cylinder I think it is just the cooling fins harmonic vibration on firing... I hope.

Now if a valve adjustment was as easy as my BMW R1100s... I'm sure I'll get the process down.

Joe
 
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