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Discussion Starter #1
How screwed am I?



I know the washers are a weak point, but even with a good washer, getting one to sit properly on that shaft is looking pretty shaky...
 

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Mr Leakered
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Yeah. Your output shaft is looking pretty rough. The hole in it is threaded. You could get a machine shop to fab a cap with the proper depth (unsplined) and hole pattern to match the retainer. With a bolt through the middle, the sprocket would be fixed in place. This would be used in conjunction with a retainer.

Heck, even a plate with with two spacers of the right length and longer retainer​ bolts could work.

Have a good one.
 

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Reminds me of how my lock washer looked on my thread "Counter shaft lock washer failure". I can attest to how easy it is to have happen when you're not aware of the need to replace it every time the counter shaft sprocket is replaced and to keep an eye on it in case. Apparently, mine had not been replaced like it should have been and I wasn't aware of a problem until I saw the sprocket was completely loose.
 

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This thread made me decide to look at mine, am I glad did! Lock washer was already pretty much worn out after about 4k miles due to the extra float my sprocket now has on the spline. If I had let it go another 1k, it probably would would have come completely loose like it had before. Seriously considering coming up with something along the lines of what Tonered suggested. I can see the problem only getting worse the longer it goes as is.
 

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Can't stress enough the need to lube the spline/sprocket. Use Anti-seize as it'll last longer vs grease. Review every 5-6k miles. Re-apply grease at that point.

Given rust on shaft, I doubt it had grease or lube at any time in recent past. S
 

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Mr Leakered
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Wear between the countershaft splines and sprocket splines is very rare on the STs. BMWs (and Urals) have that problem though. What we are seeing here is wear of the shaft due to the locking plate which is opening up the securing groove.

As noted by Brad (bikeboy) in the past, this is the wrong application for what you are suggesting. If you feel that you must apply something on the splines, this is the right product:
https://www.amazon.com/Honda-08798-9010-MOLY-PASTE-M77/dp/B0083BWUYW

Have a good one.
 

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You misinterpret my comment re lubrication and the intended purpose. It allows unimpeded float of the sprocket on the counter shaft splines. Restriction of the sprocket with the lock ring in wrong position will lead to such excessive and premature wear. Race cars (stock car types) using the Ford 9 inch clean and lube the splines to avoid lapping and excessive wear on the drive plates. Common to do to avoid the wear issue.

HAGO

Steve
 

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Mr Leakered
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Sorry, but I did not misinterpret.

This older style of locking the sprocket is great for maintenance and quick changes, but not so good for longevity. There is very little inboard / outboard play in the as-new setup. Play is introduced as the retainer and shaft eat into each other, esp when the retainer is badly worn as can be seen as steps in the original pic. The 2004+ STs have the more standard, high torque nut to lock down the sprocket laterally. Inboard / outboard play is not a good thing for wear, this is not a slip joint.

Ancient nascar rear differentials have little to do with our application.

A supplementary keeper with the depth that holds the sprocket in place laterally will, however minimally, reduce wear. Given the amount of wear in the OP, something is needed or a total rebuild will be needed.

Have a good one.
 

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Sorry, but I did not misinterpret.

This older style of locking the sprocket is great for maintenance and quick changes, but not so good for longevity. There is very little inboard / outboard play in the as-new setup. Play is introduced as the retainer and shaft eat into each other, esp when the retainer is badly worn as can be seen as steps in the original pic. The 2004+ STs have the more standard, high torque nut to lock down the sprocket laterally. Inboard / outboard play is not a good thing for wear, this is not a slip joint.

Ancient nascar rear differentials have little to do with our application.

A supplementary keeper with the depth that holds the sprocket in place laterally will, however minimally, reduce wear. Given the amount of wear in the OP, something is needed or a total rebuild will be needed.

Have a good one.

I agree based on what I've seen with my setup, very similar to the OP's without quite the amount of damage to the splines. The overall excessive float on the spline hasn't done anything any favors.
 

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Discussion Starter #11
Well, I have a new washer ordered and, the mail working like it should, I should have it tomorrow. I picked up a large fender washer at the hardware store and drilled holes to match the lock washer and will bolt that to the end of the shaft and screw the lock plate to the sprocket with the bolts passing through that fender washer. That will hold the lock washer against the outer side of the shaft slot (the side that is not worn). I tested it with worm out washer tonight and it holds great. Zero slop. There will be a slight clearance issue with the chain guard, but that is easily overcome-able.
 

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Mr Leakered
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That is a good start, but without spacers in there, the retainer bolts cannot be properly torqued and could work their way out even with thread lock. Also, you did get longer retainer bolts. Right?

I'm just throwing that out there because you are getting off easy with a small mod. It would be crappy to have it lead to crankcase, swing arm, or clutch damage down the road if the retainer bolts fall out.

There is already the possibility of the bolt in the shaft working loose (it ain't gonna get tighter!). At least that is a visual check. Along that line, it would be good to cut a check hole in the original cover or pick up the inexpensive sprocket cover that desmotimes sells.

Edit: if the shaft bolt goes missing, it isn't going to cause damage. It will only allow the sprocket to float around again. The primary goal is to secure the sprocket. Secondly is to prevent it from riding and rubbing on the inner and outer shaft splines.

Finally, do you have a Case Saver in there?

Have a good one.
 

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Yeah, I've been exactly here, just recently. It's imperative you have slop in your plate centre hole, so that the sprocket can float around a bit. There's no way you will be able to keep it from coming undone otherwise. I made a plate like you have done, spaced it out (so the sprocket sits adjacent the groove in the countershaft, where it normally would) with a couple of washers and bolted and locktited with the 2 bolts through the sprocket. I then took an M8 bolt and washer, fashioned a boss just slightly thicker than the plate I made, and drilled the centre hole in the plate slightly larger than the boss. I find it a bit hard to describe, but what you need to end up with is 1. the plate firmly attached to the sprocket, 2. the M8 bolt firmly locked in to the countershaft (output shaft) and 3. still have the sprocket " floating" on the spline so that all forces, snatching etc is independent of your locking plate - this way there is no strain on it at all - it's just controlling sprocket "end float" if you will.
 

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Mr Leakered
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Sorry, but thinking about the no spacer setup also worries me about loading the retainer plate in direct tension. That doesn't feel like a good option, even more so for a partially worn output shaft. It just wasn't designed for that type of loading, and I believe that you will find the plate and shaft wearing in a short time.

Again, sorry to be a wet blank.

Have a good one.
 

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Yeah, I've been exactly here, just recently. It's imperative you have slop in your plate centre hole, so that the sprocket can float around a bit. There's no way you will be able to keep it from coming undone otherwise. I made a plate like you have done, spaced it out (so the sprocket sits adjacent the groove in the countershaft, where it normally would) with a couple of washers and bolted and locktited with the 2 bolts through the sprocket. I then took an M8 bolt and washer, fashioned a boss just slightly thicker than the plate I made, and drilled the centre hole in the plate slightly larger than the boss. I find it a bit hard to describe, but what you need to end up with is 1. the plate firmly attached to the sprocket, 2. the M8 bolt firmly locked in to the countershaft (output shaft) and 3. still have the sprocket " floating" on the spline so that all forces, snatching etc is independent of your locking plate - this way there is no strain on it at all - it's just controlling sprocket "end float" if you will.

Any way you could post some pics? I'm trying to come up with a solution myself and I'm sure it would help the OP and anyone else that is considering this option.

What I was hoping for was a way to reduce rotational slop. Am I correct in thinking that their's no way to control rotational slop without restricting the float. To me, controlling the rotational slop contributes greatly to reducing wear on the locking plate and the splines....Right? Still don't understand why their needs to be a certain amount of float when most other countershaft sprockets on other bikes don't seem to have any.
 

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How about something as simple as this? Flange bolt threaded into the shaft with a washer fitting tightly between the bolts holding on the lock washer. Greatly reduces the float while still allowing movement, also provides a fail safe if the lock washer should fail after becoming worn. Didn't have to space the counter shaft cover much to clear.
 

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Any way you could post some pics? I'm trying to come up with a solution myself and I'm sure it would help the OP and anyone else that is considering this option.

What I was hoping for was a way to reduce rotational slop. Am I correct in thinking that their's no way to control rotational slop without restricting the float. To me, controlling the rotational slop contributes greatly to reducing wear on the locking plate and the splines....Right? Still don't understand why their needs to be a certain amount of float when most other countershaft sprockets on other bikes don't seem to have any.
OK,I'll try and get a pic tonight when I get home from work.
Even the new sprocket I fitted is not a tight fit on the splines, my splines may be worn but the slop doesn't seem much worse than some of the other bikes I've had. The OEM keeper plate is not there to control this "rotational slop". It is purely keeping the sprocket in the correct lateral position on the spline. I don't believe it's necessary or viable to try and lock the sprocket rigidly onto the output shaft, given the system Ducati has presented us with here. They obviously didn't think the sprocket had to be locked to the output shaft, so I'm happy to run with that. My plate has been on there for about 1500km so far with no sign of any problem. Like the OP, I had to do something because the inner edge of the keeper plate groove had become chamfered. The wear areas on my plate, being the end of the shaft and a washer under the head of the M8 bolt, are greater in area than the "mis aligned keeper plate tags"so I'm hoping I've got it sussed - time will tell .....
 

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Here are a couple of pics. Please bear in mind I fashioned this solution by hand , in a hurry because I wanted to go for a ride (as always!). You can see the new black OEM keeper plate against the sprocket, then 3 washers which space my additional plate to just flush with the end of the countershaft. The most important bit is not visible - the central boss which allows tightening the M8 bolt, while allowing the sprocket to move around - rotational slop as Bryanc123 puts it, is not impeded or transferred to the additional keeper plate. It seems to be working fine. I needed to put a washer under each of the 2 plastic cover boltholes to prevent the M8 bolt head wearing on the inside of the cover.
And, no Tonered, I didn't put longer retainer bolts in, but I looked long and hard at the originals and I sure would have put some longer ones in if I'd had some, but, well, you know, the twisty roads were calling me :)
 

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Mr Leakered
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I like it.

I do not understand the hidden boss aspect, but it looks great.

If it is holding that life is good. If it was my bike, it might grab some longer bolts the next time I'm at the store, just to give myself a warm, fuzzy feeling.

Have a good one.
 
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