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The same fitment question re cush drive compatibility (see below) was posted to the ESJOT product page and their response was it works. Nothing is certain until you try it, but you might send them a query and assuming they confirm its fit you'd think a return would be possible should it not work.

"Question: Hi, I am after a rear sprocket for my ducati Supersport 939 (2017)I haven't yet replaced the sprockets on a ducati and I'm aware they fit on differently. A lot of after market sprockets come with carriers or cush drives etc.I just want to confirm my existing OEM cushdrive etc. will be perfectly compatible with this sprocket and no extra parts will be required. Stock pitch is 520Thanks.
September / 25 / 2020
Answer: This sprocket is plug and play, fits the same way will fit the oem Ducati rear sprocket."
Right, that's the query I was referring to.

But that's in doubt.

This is an issue the the forum should solve, once and for all.
 

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There are actually alternatives which are reasonably priced. I have 43 tooth (did'nt notice it was a tooth off in the link) ESJOT sprocket hanging on the garage wall as an ornament. I bought a complete set when my front sprocket wore out, but didn't replace the rear as there was very little wear on the original.

Shipping within EU is very reasonable, but be prepared to pay for customs as well, when ordering from abroads.There might be some depending on where you live.
Taken your advice and ordered both sprockets and DID chain. Hopefully all will fit.
 

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Wow, 4 days ago I ordered this from Italy. The package was delivered just now. The entire cost was 141 Euros, perhaps I'll take it in the shorts for the conversion but it should be about $175. Not really a bad deal if it fits. Got the DID X-ring Pro Street chain. Not the heaviest chain but I am guessing a good match to the SS. (First time I've not purchased a heavy EK chain but thought I'd give it a try.) I think I was out about $150 for the chain & sprockets on my Bandit last time, so this is right in the ballpark.

Since I'm getting my 18k service next week, I thought I'd get it put on then. Then get a few hundred miles on it to readjust the chain before taking off to Arkansas week following.

43427


I just notice the chain says 800cc max. I guess it's my fault. I saw 1100cc on the DID website but that was for the 530 chain. That might be $100 down the drain, so beware when you order.
 

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I wouldn't have any concerns about using it.
 
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I bet that 800cc warning is for 4 cylinder bikes. The Supersport is about like 600cc power. I would not have any concerns either. Your going to have a nearly new bike for the Arkansas trip! 😊
 

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Wow, 4 days ago I ordered this from Italy. The package was delivered just now. The entire cost was 141 Euros, perhaps I'll take it in the shorts for the conversion but it should be about $175. Not really a bad deal if it fits. Got the DID X-ring Pro Street chain. Not the heaviest chain but I am guessing a good match to the SS. (First time I've not purchased a heavy EK chain but thought I'd give it a try.) I think I was out about $150 for the chain & sprockets on my Bandit last time, so this is right in the ballpark.

Since I'm getting my 18k service next week, I thought I'd get it put on then. Then get a few hundred miles on it to readjust the chain before taking off to Arkansas week following.

View attachment 43427

I just notice the chain says 800cc max. I guess it's my fault. I saw 1100cc on the DID website but that was for the 530 chain. That might be $100 down the drain, so beware when you order.
Before ordering the OEM rear sprocket I went to order the ESJOT sprocket... but they were not in stock... think you got it. All good, I went for the OEM sprockets and the DID ZVMX gold. OEM sprockets need to come from Italy, should be here end of next week. My local dealer that services my bike dropped Ducati, and the other dealer here lost their mechanic so I'm going to have my local INDI Ducati service center put it together. Need to get my 18K service shortly, guess I'll bring it to Chicago and have my friend's shop, TeamMCC, do it, they have 3 certified mechanics, only place I trust. What a hassle, hard to believe that's the state of things in ATL with some of the best motorcycle roads, go figure.
 

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I'll be doggone. I guess I did get the last one. But the 44 tooth is in stock. Might be a good set up with 15T size front?

I don't know what to do with chain. I'm thinking I might use it and keep the original sprockets on there and wear them out together. If I put on the new sprockets, I'll want the heavier chain. Defeats the purpose otherwise.
 

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I bet that 800cc warning is for 4 cylinder bikes. The Supersport is about like 600cc power. I would not have any concerns either. Your going to have a nearly new bike for the Arkansas trip! 😊
I think you'll find a capacity rating like that is based on torque, not outright HP. In which case it might be a tad underdone for the SuperSport.

I wouldn't be too concerned, I can't see it self destructing when it reads the engine size and its probably a lot better than the chains from the bad old days, or new chains from no-name manufacturers.
 

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Yes, agree that it's torque which is largely correlation to engine size. Although those hi performance bikes usually build torque peak at high RPMs unlike traditionally automotive engines.
GSXR-750: 64 ft-lb @ 11200 rpm
SS 939: 71.5 lb-ft @ 6500 rpm
 

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Yes, it's torque that matters, but it's the torque the chain see's, not the torque at the crank that counts. 600cc fours make less of the latter, but about the same of the former, due to tighter gearing.
 

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The equation isn't descriptive since torque is power measured under 5252 RPM and HP power above. So much for the harder twist vs speed analogy. And that GSXR 750 has a bunch more HP (140), rpm (14k) and gearing.

I've seen "metric" dyno readings where the torque and HP lines never cross. They apparently use a different formula that might more adequately explain the "twist" vs "speed" explanation.

Actually, I am clueless. The first formula seems to make little distinction between HP and torque other than RPMs. And I've never seen how they compute the second method that might shed some light.
 

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The equation isn't descriptive since torque is power measured under 5252 RPM and HP power above. So much for the harder twist vs speed analogy. And that GSXR 750 has a bunch more HP (140), rpm (14k) and gearing.

I've seen "metric" dyno readings where the torque and HP lines never cross. They apparently use a different formula that might more adequately explain the "twist" vs "speed" explanation.

Actually, I am clueless. The first formula seems to make little distinction between HP and torque other than RPMs. And I've never seen how they compute the second method that might shed some light.
The 5252 crossover point is just a function of the units, nothing magic about it. Different units of measurement, like the metric system, will yield a different crossover point, but the physics doesn't change.
Torque is force, horsepower is power, which is basically force times speed. RPM doesn't change that. Regardless of the units, HP is torque times rpm.

Guess which engines are the "torquiest" if by that we mean the amount of torque per cc? The 600cc fours. :)
 
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...The first formula seems to make little distinction between HP and torque other than RPMs. And I've never seen how they compute the second method that might shed some light.
Torque and horsepower are directly related. In simple terms, power is torque multiplied by RPM (although there are other multipliers involved).

Torque is indirectly related to swept displacement. Engine manufacturers can play with bore, stoke, engine layout, crank offset etc etc etc to develop more torque but it usually comes at the expense of ability to rev.

What generally happens is torque peaks and although it starts to fall off, power still increases because the revs are still climbing. Power continues to increase until the increased revs are not enough to c compensate for the drop in power.
 
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Right Steve and Rich.....so what does it all mean? HP vs Torque? My 800cc chain?

it's contradictory logic to my mind.

(I still don't understand equal length headers for 90 degree V twin in a single collector as gospel- I'm pretty dense sometimes)
 

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Ignore outright power, it's the torque that's trying to stretch your chain. And, the lower the gear the greater the torque.

But it's all somewhat academic. Racers have been known to change their 530 chains on the litre plus bikes for a 520. It's lighter and supposedly has less friction loss. They even will use plain chains, not those with o-rings (or x rings, or d rings etc etc etc) to avoid frictional losses. The trade-off is increased wear. I can't see links stretching, it's in the bearings and larger bearings have a larger surface area and last a bit longer.

The SuperSport comes standard with a 106 link 520 chain. We know it's good for about 15,000 to 20,000 km. Sprockets usually wear before the chain is too bad (or at least in my case). I don't know why a manufacturer would claim it's for a maximum of 800cc, most of the discussion here has been that peak torque or power would be a better benchmark, but it's a moot point. Maybe their lawyers thought it was a good idea.

Don't worry about it, a 520 is the correct chain according to Ducati.
 

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Ignore outright power, it's the torque that's trying to stretch your chain. And, the lower the gear the greater the torque.

But it's all somewhat academic. Racers have been known to change their 530 chains on the litre plus bikes for a 520. It's lighter and supposedly has less friction loss. They even will use plain chains, not those with o-rings (or x rings, or d rings etc etc etc) to avoid frictional losses. The trade-off is increased wear. I can't see links stretching, it's in the bearings and larger bearings have a larger surface area and last a bit longer.

The SuperSport comes standard with a 106 link 520 chain. We know it's good for about 15,000 to 20,000 km. Sprockets usually wear before the chain is too bad (or at least in my case). I don't know why a manufacturer would claim it's for a maximum of 800cc, most of the discussion here has been that peak torque or power would be a better benchmark, but it's a moot point. Maybe their lawyers thought it was a good idea.

Don't worry about it, a 520 is the correct chain according to Ducati.
520 isn't the issue. The explanations for the differences in the chains was mentioned in earlier posts.

I've gotten 18k miles out of my OEM chain (30k KM).

The formula with torque and HP remains a mystery to me.
 
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