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Author Topic: How to lose unsprung rear weight (single-sided swingarm cush drive joys)  (Read 28169 times)
ellingly
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« on: January 31, 2010, 02:28:19 AM »

How to lose some unsprung rear weight: machine your eccentric hub.





Pretty simply - cush drives failed, exited my rear sprocket, ate the eccentric hub. Not the first this has happened to, won't be the last. Mine happened to fail exceptionally quickly for a reason I'm not going to discuss on a public forum. Normally you get a LOT more warning of these guys failing. Mine ate the hub in < 400 km and less than a week and a half.

Oh, and I noticed them the day before I was embarking on an epic 1200km single day trek on some awesome motorcycling roads.

Next few posts will be a story of how to pull the hub out. Hub removed is where I am at the moment. I've got a second-hand hub which I am going to freshen up with a new special SKF bearing on the sprocket side, and then I'll also post up how to put this all back together.
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« Reply #1 on: January 31, 2010, 02:30:22 AM »

We start with an unmolested rear end.



The wheel nut has a safety pin through it (this applies to the sprocket side, too. We need to undo nuts on both the wheel and the sprocket side of the rear end). I like to make sure my pins can't come out, so a little cable tie is used to hold the ends together.



This nut is 46mm. The sprocket nut is 41mm. A little bit larger than most people's 1/2" drive socket sets go up to. One option is to get a 3/4" drive socket set; another is a very nifty tool made from billet aluminium.


Socket suitable for 41mm sprocket side nut.


Socket suitable for 46mm wheel side nut.

I bought this as a backup plan on the road - just in case I need to do something with the rear nuts in the middle of nowhere, and they don't happen to have an appropriately sized socket. The nuts on the rear axle are very, very, very tight: the wheel nut is torqued to 176 Nm, and the sprocket nut is torqued to 156 Nm. From this point, they are then tightened so the safety pins can be engaged through holes in the axles, necessitating up to a further 1/8 of a turn.

This means you want to use a long bar.



A good breaker bar is essential. If you were using a 3/4" drive socket and had an appropriately beefy rattle gun, you could maybe rattle it off, but you need a bar to be able to do it up again to the right torque. Here is my breaker bar as well as the handle for my floor jack for my car. 1.5' breaker bar + 4' of other bar gives an appropriate amount of leverage.

Undoing these nuts yourself can be a bit of a pain. I find the easiest way is with the bike in gear, on the sidestand, and with chocks under the front and rear wheels. Note you need to think about which way these chocks need to be - both nuts are right-handed (normal) thread: when you undo the wheel nut, the chocks need to be behind the wheels, and when you undo the sprocket nut, they need to be in front. The sprocket nut is the scary one - if it moves the bike too far it will fall off the sidestand.





Note these are set up how you would do the sprocket nut. They need to be on the other side of the wheels for the wheel nut.

At this point, remove the safety pin from the nuts, and get cracking. We simply want to loosen off the nuts.



It's best when cracking the nuts to be pushing DOWN with the long bar. This forces the tyre into the ground and stops it spinning. Alternatively, if you have the right setup, you can stand on the rear wheel and pull the bar to crack the nuts. This will also serve to stop the wheel spinning.

The chain also needs to be de-adjusted. This can be achieved with the bike on the rear stand later, but I find it is easier to undo the two pinch bolts to de-adjust the chain. For those not in the know, the eccentric hub is stopped from turning by two bolts in the back of the swingarm. These are tightened up and ensure the hub cannot spin. They are 14mm hex-headed bolts, and to get to them one generally needs a small extension on a rachet.



You de-adjust the chain using an appropriately sized C-spanner. I like my C-spanner, it fits under the seat and weighs bugger-all.



You need to spin the eccentric hub clockwise to de-adjust the chain (direction given as you look at the sprocket). Loosen the chain as much as is practicable - this makes it easier to disengage it from the sprocket when required.



I also like to remove the exhausts as it makes life much easier when pulling the rear wheel off.



We're now at a point where we can lift the back end off the ground. There are many ways to acheive this; I will discuss how I did it but it certainly is neither the only nor the best way to do it.

Firstly, I lifted the rear wheel off the ground wth my rear stand. I then placed a dual-sided swingarm rear stand under the front forks, with the swingarm plates rather than the hooks to engage pickup knobs. To stop the steering moving, I used two straps, one on each side, which were both tightened around the handlebars. This makes sure the steering stays dead ahead. I then lifted the front wheel off the ground, and used two rachet straps to strap the front down to the front stand. This adds friction and stops the bottom of the forks sliding off the plates on the front stand. To help balance, I also tied a compressor (which is nice and heavy) to the front end; this compressor was also used to hold the lifting end of the front stand down. To make sure the wheel could not fall very far, I used the two metal chocks to help hold the front appropriately.



With this done, I then used a car scissor jack to lift the back of the bike. The scissor jack is placed under the engine, as far back as is possible, and then this is raised. I used a small piece of wood and a rag to protect the bottom of the engine. With the bike lifted, I placed car axle stands under the solid portions of the rider's footpeg mounts. This helps to stabilise the bike from tipping over. I then removed the rear stand, and the bike was elevated with the rear wheel off the ground. It is also very stable, even though it looks slightly dodgy.



With the rear end lifted, the rear wheel can be removed. Undo the rear nut.



Remove the washer and the conical seating washer.



The wheel is then free to be removed.





In this picture you can see the drive dogs from the rear axle/rear brake assembly. Upon reassembly it is vitally important that these properly engage the holes in the rear wheel, otherwise the rear wheel will crack in the middle.

Next we remove the rear sprocket. We can either disengage the chain first or remove the nut; I found it easier to remove the sprocket nut first.







With the nuts removed, pull the chain to one side and spin and wiggle the rear sprocket. The chain will then disengage from the sprocket, allowing the removal of the rear sprocket.



The sprocket and a further conical seating washer are then simply removed.





In the shot with the sprocket removed, it is a bit more obvious as to the damage caused by the failure of the cush drives.

Just to highlight it a bit more, here is another shot.



Note the notches for the C-spanner to engage. They are approximately 1.5mm deep which means the C-spanner now slips out of them. They are normally close to 10mm in depth. The eccentricity of the hub is also apparent in this shot.

The cush drives themselves don't look too scary.



Note that the cush drives are properly mounted here. This was in an attempt to get me down to Melbourne - but the metal outer and rubber portions are clearly separated from the central bolts of the cush drives.

Lack of decent lighting to finish the photography means that this is where the removal finished yesterday. More to come. I end, however, on a handy hint. It can be easy to lose all of the washers and spacers from the rear end. I like to keep things together and in order, which is where our friend the cable tie comes in.



Stay tuned for the removal of the hub itself, and why the hell I bought an AU$208 bearing.
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« Reply #2 on: January 31, 2010, 02:31:55 AM »

The next stage in the removal of the eccentric hub is to remove the rear brake caliper. The factory manual says you have to drain the circuit and remove the caliper fully. Stuff that for a joke - Ducati rear brakes are an absolute pain to bleed. Instead, you just undo the two caliper mounting bolts and hang it from the swingarm using some cable ties.



The bolts you have to do here are the ones closest to the swingarm (and the ones furthest apart). The others dismantle the caliper. Not so useful.

The brake caliper holds the rear axle from moving side to side. With it out of the way, you can push the rear axle out to the wheel side. The factory manual say this is easy: just pull on the axle.

This is a crock of shit. You have to use a rubber mallet and carefully tap the sprocket side of the axle (not too hard - don't bend the axle) while pulling on the brake disc.



Once the axle is removed, set it aside, unless you wish to use it to hit the designer of the Ducati cush drives over their head. It would make an excellent club.



With the axle out of the way, you get to the most fun experience of this whole process. There is a circlip which retains the hub from lateral movement. This needs to be removed.



It is a large circlip and it is under a LOT of preload. You need to use good, strong and BIG circlip pliers.

As I didn't have ones that met these criteria, I borrowed a friend's.



As I said, this circlip is massive and has a huge amount of preload. The holes are about 20mm apart when installed. They need to be stretched to 40mm apart to remove; once removed, they are around 10mm apart. This is quite a considerable amount to open this external circlip. There are no more photos here as I spent the next twenty minutes swearing as the bloody thing is very hard to get off.

But, once you are rewarded by the circlip springing across your garage and embedding itself in the plasterboard wall, you can retrieve it and photograph it and the washer that sits between it and the caliper bracket.



The next thing to come off is the caliper mounting bracket. Simply pull it off.



Behind this (between it and the swignarm) is another washer. I cable-tied this washer to the caliper mount which I also hung out of the way and cable-tied it to the swingarm. If you wish to fully remove it from the bike, there is a single capscrew to remove the speed sensor from the bracket. I'm happy to just have it hanging around for a while.

With this done, the hub can be removed. Ducati say that you simply press on the wheel side of the hub and remove it from the sprocket side of the swingarm. Again, this is a crock of shit. There is so much sticky grease in there that there is no way to simply do this. I squirted a heap of penetrene into to the swingarm to loosen it up, and even still I had to use a piece of plastic to lever the swingarm open slightly and a rubber mallet to tap the hub free. You probably are about to find out how well suspended your bike is.





At some point in the future, you will have removed the hub, after swearing at least 12 times. You can clean up the hole in the swingarm as it makes you feel like you have accomplished something, and bask in the glory that is an empty hub shell.



At this point, you also may inspect the damage to the hub.



Doesn't look too bad from this angle, you can still see the cutouts for the c-spanner to engage. Does look to be a bit of swarf from the machining done by the cush drives, however.



To give those reading along a sense of how much material has come off, it's wise to inspect the hub from the side.





The bit that the C-spanner engages to is meant to be as tall as the central part. I have lost about 1 cm off the hub here, and the 2mm remaining is nowhere sufficient to adjust the chain properly. It wouldn't have taken too much more to have eaten the swingarm.

Next time in this thread, I need to measure the replacement hub and make sure it will fit in the swingarm, and then start pressing the sprocket-side bearings out, and pressing a new bearing in. I'll explain this in the next post.
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« Reply #3 on: January 31, 2010, 02:35:40 AM »

So, this super sexy special bearing. Ducati say you cannot rebuild the rear hub, you have to renew it as a unit. They are not cheap  bang head.

I managed to pick up a cheap rear hub on eBay. It smelt pretty strongly of degreaser and the bearing on the sprocket side is a little bit notchy. It hadn't done many kays but you never know how these things have been treated.

The sprocket bearing is a very special double-row angular contact bearing from SKF. Part number is BAH-0062. If you ring up an SKF stockist they can special order it from the factory who make this bearing in Spain. You can get them a little cheaper from the UK or the US, esp. if you live there Smiley but I bought mine from a local SKF dealer. Total cost was AU$208 for the bearing. Add in another $100 for my hub including postage and we're still AU$2200 below the retail cost of the hub.

The other bearing is a needle bearing and much easier to refresh.

So where we sit now is that I have a hub removed, and I have a spare hub and bearing. It's off to the engineer to press out the bearing and give me a refreshed hub. Then it can all go back together Smiley.
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« Reply #4 on: January 31, 2010, 09:20:17 AM »

Get a sprocket carrier with machined lips to prevent the cush drive outer sleeves from moving.


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« Reply #5 on: January 31, 2010, 11:36:40 AM »

That's the plan. Well, it was the plan to get one when I needed a new sprocket, which wasn't too far away, but oh well.
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« Reply #6 on: February 01, 2010, 06:25:34 PM »

you picked one hell of a way to work on the rear of that bike. using the rear for the front and a jack for the rear. lol
good write up. My eccentric was just as hard to get off. and those circlips were probably the hardest part to remove out of the whole thing!
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« Reply #7 on: February 01, 2010, 08:19:21 PM »

you picked one hell of a way to work on the rear of that bike. using the rear for the front and a jack for the rear. lol
good write up. My eccentric was just as hard to get off. and those circlips were probably the hardest part to remove out of the whole thing!
The way the mechanic who helped me out with trying to get me on the road so I could do my epic Christmas trip raises the rear in the following way:
* Rachet straps off the lower triple to tie it down to solid mounting points in the front
* Car jack under the sump.

Works a bloody treat. Garage floor concrete here is waaaay too pissweak to hold a decent eyebolt in, so lifting it so the front is stable, then raising the rear works as a pretty good compromise.

I do expect the pic to make it to thereifixedit.com or somewhere like that Tongue. Or failblog if the bastard falls over.
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« Reply #8 on: February 03, 2010, 07:23:37 AM »

this writeup is incredible. I cannot believe the amount of material that was removed from the hub. unbelievable.
i'm checking mine next time i go look at the bike.
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« Reply #9 on: February 03, 2010, 09:54:54 AM »

With the hub removed I can definitely confirm that an SBK hub does not fit an S*R series Monster. The ONLY difference is that the outer diameter is 8mm larger for an S*R series Monster hub. The widths and the eccentricity of the two hubs are identical. Effectively, it appears that the SBK hub has more material machined off the main diameter.

Bugger. I have a second second-hand hub on order; anyone want a 996 hub? Cheesy. I'll just resell the one I bought, as I picked it up cheap.

Oh well, pressing on, a friend of mine at work who happens to have a 20 tonne press in his shed (among other awesome machinery) assisted me with the next part. I want to have the hub as fresh as possible, and given I am buying a second-hand hub.

The relevant bearing to change is the sprocket-side bearing, which is SKF part number BAH-0062. This is a special-order part; SKF dealers CAN obtain it but they need to be leant on. The SKF dealer in Canberra charged me AU$204.50 including freight from Spain (which is $3.50 cheaper than their original quote). This bearing is a very special double-row angular contact bearing, much like a car wheel bearing, and is designed to be compact yet still have zero play once both sides are preloaded and support both high axial and radial loads. It's a pretty funky deal; I actually sacrificed the one from my dead hub in the interests of this thread. I like to know what is inside things Smiley.

While I have both the SBK and S*R hub in my possession, let's look at the material removed by the cush drives.



Here's a perspective view. You can see the full height of the C-spanner engagement lugs (for the purposes of turning the eccentric for chain adjustment) on the SBK hub on the left. On the right is my hub after the cush drives have machined material from it. Note the cush drives rotate concentrically with the axle, but are wide enough to remove material even from the furthest point from the axle on the hub outer.



Here's a view from side on. You can see just how much thickness has been removed. The Monster hub on the left only has 1.1 mm of material left on the C-spanner engagement lugs.

You can also see the more intricate machining of the SBK hub. The SBK hub weighs about 100 g less; this corresponds to the 4 mm wall thickness cylinder of material removed by machining on the SBK hub. Both hubs have identical dimensions other than the diameter of the large cylindrical body of the hub. Bugger.

The sprocket bearing is the really sexy double-row angular contact bearing, as stated above this is SKF part number BAH-0062. This is what it looks like installed.



There is a circlip retaining this bearing. Remove this internal circlip. To remove this bearing, head the body of the hub using a heat gun until it is just too warm to touch (which is about 80 or 90ºC). You need to make a small attachment so you can press the bearing from the rear; because you cannot access the outer shell, you have to press on the inner race.

In terms of force required, at about 80ºC, the bearing comes out with minimal pressing. In fact, my friend stated that it required just the weight of the press handle to ease it out with zero juddering. Easy peasy. It might fall out more easily with more heat but you don't want to destroy the metallurgy of the hub by heating it too much and annealing it.

This is really good news. Ducati say you can't service the hub, and we feared the bearing would be held in with retaining compound. It isn't, and it presses out very nicely.



Looks pretty nifty once removed. The yellowy stuff in there is grease, perhaps used upon installation. Note the bearing is a tight fit axially, held by a shoulder at the back, and the circlip (positioned in the grove at the top of the bearing hole) at the front.



That would be the circlip and a sprocket bearing.

You can definitely buy a new bearing from SKF, too.



In the interests of science (don't argue with it), I sacrificed the old bearing from my hub to show everyone a look inside.

Firstly, one chucks a screwdriver between the two inner races, and twists. This uses the races to pull the seals out.



With that done it's then easy to work your way around the outer of the seal with a small jeweler's screwdriver, removing the seal fully.



You're then free to pop out the inner race and the balls.



As you can see, the inner and outer races are curved such that the load is supported both axially and radially: very different from a standard bearing! Also, given how the two halves are machined, once the bearing is loaded from both sides, which it is with the axle installed, then there is no sideways movement. Very neat.

For those who are a bit more mechanically minded, this is just like a car wheel bearing, except the outer diameter is smaller: this is a 35 mm inner, 62 mm outer diameter bearing (3562); a standard car wheel bearing for a small hatchback is a 3572 bearing.

The bearing looks absolutely new. Note this has done ~25 000 km, some high speed stuff in that too, and you can still see all the grinding marks on the races.



The inner race is likewise just as clean (small spot is actually a tiny bit of grease I didn't wipe up).



The balls look new, too.



On the topic of the grease - it's actually a lot more easily liquidated than a usual high-temperature wheel bearing grease. Definitely synthetic, and not like any of the range of greases I have in the shed (which are a good cross-section of available greases). SKF say this bearing is sealed and lubricated for life, and they clearly have done a lot of work on what it needs, cause the bearing is in pretty good condition internally!

The other end of the hub, which is the wheel end, is a lot more boring and I haven't yet had this fully disassembled (though in the name of science we are going to try). The wheel end houses a needle bearing, hidden behind a seal and a circlip.



Pretty easy to gently remove the outer seal, behind which hides a circlip.



Hidden behind this you can make out the bearing. It is a Torrington NK42/30A needle bearing. It is sealed on the internal end, too, meaning the hub has two fully sealed bearings.



Removing the wheel bearing might be a bit more interesting, but I'll report on how hard this is to do later.
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« Reply #10 on: February 03, 2010, 10:08:44 AM »

Ellingly, thanks a bunch for the detailed write-up, fantastic job!  chug
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« Reply #11 on: February 04, 2010, 04:54:03 AM »

Prompted by some questions on another forum about how the cush drives go into the sprocket and a few other things, here's a bit of a diversion. I'm including it here on my tutorial in the DMF for completeness.

Tonight I dismantled the old sprocket which had the wrecked cush drives in it. They didn't look too destroyed cause I and a local mechanic did our level best to keep me on the road so I could go on a Christmas trip, but that didn't happen.

The whole rear sprocket assembly consists of the sprocket, 5 cush drives which bolt through to the drive hub which sits on the front of the sprocket. The only mechanical connection between the drive coming into the chain and the drive hub (which has a splined centre to engage on the rear axle) is through the 5 cush drives.



Ducati, in their infinte wisdom, do not have a mechanism to retain the cush drives from falling out the back of the sprocket. They're actually slightly tight to push into the holes into the sprocket but there's no retaining compound on the outer shells, and no tabs like there are on aftermarket single-sided swingarm sprockets.



The rear view of the sprocket shows that the cush drives have allen bolts through them. These are bonded to the rubber; the rubber does fail around these bolts though. You need to hold these allen bolts to undo (or do up) the cush drive nuts that holds the drive hub on.

Enter nifty method I first saw on one of Chris Kelly's (from Ca-Cycleworks) videos to hold the cush drives and do it all by yourself Smiley.

Grab a big bar, and a 12mm allen key socket. 1/2" drive is a good size for this - it's a beefy allen key! Clamp the bar down to a bench or something solid. I'm actually using a work platform, which I sit on when I undo the nuts.



You then just sit the cush drive on the head of the allen socket such that the weight of the sprocket pulls the moveabe head of the breaker bar down, holding it all pretty steady.





It's then simply a matter of pulling the rachet so that the sprocket doesn't want to move too much, and yanking hard. The nuts holding the drive hub on, after all, are lock nuts.

Once all the nuts are done, you can push the cush drives out of the sprocket.



The drive hub simply lifts off.



Oh, and when I said the drive hub nuts were lock nuts, they are. They're nuts which are mechanically pressed at the top so the topmost threads are ovoid, not round, which provides interference so they do not come undone. Tightening them against the thread of the cush drive bold makes this thread round again, but not so round they will come off.



In terms of how the cush drives fail, the rubber cracks around the bolt.



You could actually cause this sort of damage through incorrect installation, if you let the bolt turn in the rubber section. It's for this reason that I think it is a great idea to clamp the bar used to hold the back (allen key) part of the cush drive.

A damaged one will allow the bolt to separate fully from the cush drive.



Marks on the side of the cush drive casing were where a mechanic and I tried to make enough deformation so I could ride the bike from his workshop to my garage. It retained the shells well enough.

How bad's the damage? Let's compare to a cush drive that is pretty much ok.





Here ends the interlude showing the cush drives. Next up I hope to show either how to get out the wheel side needle bearing from the hub, or a destroyed hub showing you why the hell you shouldn't try to get this needle bearing out Smiley.
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« Reply #12 on: February 09, 2010, 06:26:13 PM »

An interlude: quick investigation into cush drives.

As part of my ebay purchasing, I was able to get a cheap set of 996 low mileage cush drives. I figured, if nothing else, they'd get me on the road a bit faster than waiting for some new ones.

They are identical to the ones out of my 2006 S2R1000, with the exception of the metal being a slightly different colour (more bronze in colour).


(996 cush drive on the left, S2R1k on the right)

Let's look at the most destroyed of my cush drive and see how it failed.



In this view of the central bolt from one of my failed cush drives, you can see that the rubber has nicely bonded to the central bolt in one area. Away to each side, it really was only bonded at the top, maybe about 25% of the total depth of the rubber.

This is more apart from the other side.



Note how smooth the surface looks. There's some minor pitting, which should help the rubber bond (I am guessing here they use an adhesive and then vulcanise the rubber onto the central bolt). Pretty obvious it was only bonded to 25% or 33% of depth through the rubber.

This is also very apparent when you look inside the destroyed cush drive rubber.



Not that much has actually failed! If it was bonded the whole way through, you'd think it would be a lot harder for the central bolt to separate...

As for the difference, the 996 cush drives are a different part number (I have to check my notes which are at work for these... oops!). They also say "DUCATI RACING DIVISION" on the bottom, rather than the stylised D logo in the S2R1k cush drives.

The central bolt highlights what I think is the crucial difference.



Fairly smooth looking metal on this, just like the sides of the central bolt were in the one that had fallen apart.



You can make out a bit more pitting and etching on this one: if this is carried over into the outer sides of the central bolt, you'd think it would adhere to the rubber better, and thus wouldn't separate as easily as the ones from my S2R1k.

I have some progress made. Chasing the needle bearing, just to see if it is possible to take it out, to buy one, and to put a new one back in. This is a bit more problematic, and, to be honest, perhaps not worthwhile (most of the load is taken by the sprocket bearing). The other thing I have done is rebuild my sprocket with the 996 cush drives. Going to be a few week's wait on either decent aftermarket sprocket  :crap!: so I'm hoping to get the bearing(s) replaced in the S4R hub that turned up yesterday and the whole thing back together ASAP.

Till later, dear readers!
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2006 Ducati MS2R1000 road | 1973 Suzuki GT250 cafe race | 1982 Yamaha RD250LC race | 1991 Suzuki GSXR750 perpetual project | 1984 Suzuki TS250x vintage enduro | 1997 Honda CT110 postie of death | 1982 Kawasaki KH100 bucket racer
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"Apollonia" '06 S2R 800


« Reply #13 on: February 10, 2010, 05:19:56 PM »

This is one of the most informative Tutorials I have ever seen, Excellent job Ellingly!
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Teach a man to brew, and he wastes a lifetime.

2006 Ducati S2R 800, 2004 Honda Dream 50R, 2001 Kawasaki W650, 1940 BSA M20
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« Reply #14 on: February 16, 2010, 02:53:16 AM »

"Refitting is the reverse of installation, with attention to the following few notes:"

That's the first line of the factory workshop manual regarding the refitting of the eccentric hub. Fear not, dear reader, for I shall now explain in more detail how this whole thing gets back together.

Firstly, there are a few supplies you definitely need:
Loctite 243 - used to threadlock the cush drive to drive hub nuts.
Shell Alvania RL3 grease - thickish lithium grease. Workshop manual specifies Alvania R3; Shell assure me that this has been discontinued and RL3 is the appropriate grease
Shell Retinax HDX2 grease - used for a few nuts and bolts. I couldn't actually get any, so used Castrol LMM. This is an NLGI2 grease, with moly disulphide. Black and the sort of stuff used in CV joints etc.

Picking up where we left off, we clean out the swingarm receptacle for the hub.



Liberally apply 'Grease A' to the outside of the hub. Grease A is the aforementioned Alvania RL3. Nice stuff to work with, actually. Somewhat pleasant on the hands.



I also ran a tiny film of grease all around in the swingarm.

With a plastic tool so you can't mar the swingarm, prise the swingarm open slightly, and push the hub home from the wheel side.



Now the fun really begins. All the rest of the stuff needs to be installed. On the wheel side, we have washer, rear brake caliper mount, washer, circlip. Clean the washers and the rear brake caliper mount, then apply Alvania RL3 to the first washer.



Install this washer with the 'sharp' side facing the eccentric hub. It's pretty obvious which one is the sharp side, looking at the edge, the sharp side has a nice defined cutout, the softer side doesn't. Or just remember which way it was installed from when you removed it Smiley.

Next, clean up the rear caliper mount. This is easier with the speed sensor removed - one allen headed capscrew achieves this. Grease the bit that goes over the rear hub with Alvania RL3, as well as both of the o-rings that sit against the washers.



Clean up the circlip and the washer which retain the rear caliper mount to the hub. Grease the washer with Alvania RL3.



Installing the washer is easy. Sharp side again faces the eccentric hub.



Now, using some massive circlip pliers, fully open up the circlip.



Place it against the washer.



While releasing the circlip pliers, push on the side of the circlip opposite the pliers, to make sure it is fully seated. Clearly I can't show this as I have one hand on the circlip pliers and one hand pushing the circlip home with a screwdriver. DO NOT PUSH THE CIRCLIP WITH YOUR FINGERS. YOU WILL KNOW WHEN YOU TRAP SKIN BETWEEN THE CIRCLIP AND THE REAR HUB. YOU HAVE BEEN WARNED.

With that, the circlip is installed.



Note on the circlip pliers I am using here. These are World War 1 vintage barbed wire cutters which were converted to also act as circlip pliers. The friend of mine at work (who incidentally rebuilt the rear hub I am installing here) picked them up at a swap meet in the 1980s, and, they were dug out for this special occasion.

The pliers were built in 1917. 93 years old, and still bloody useful!

The rear axle can now be installed. A teeny tiny bit of grease on the axle so it doesn't gall on the bearings (in this case, Castrol Agriplus; recommended by a few people. Twas also recommended for going on the needle bearing). Place the axle into the bearings and slide it home nice and carefully.



The rear caliper can then be installed. Push it over the rear disc.

You'll probably want to clean up the rear caliper mounting bolts at this point.


(Clean on the left, dirty on the right).

Workshop manual specifies a torque for these guys (24 Nm, +/- 5%) when they are greased with 'Grease B' which is a moly-based NLGI2 grease (Shell Retinax HDX2 mentioned at the top, or Castrol LMM in my case).



Ok, so maybe I greased the one on the right a touch too much. I took some off after taking this pic.

Nip these bolts up finger tight.



Then crack them up to 24 Nm (+/- 5%).



You'll also want to reassemble the rear sprocket. I'm waiting on my aftermarket sprocket and chain, but, the 996 cush drives and the stock sprocket will do me for the next few hundred km. I'm putting in new cush drives when the new sprocket comes, and before then, I'll be nervously looking at my cush drives every time I fill up with fuel!



Torque for these is 48 Nm, with 'Lock 2' aka Loctite 243 (medium strength, oil reistant) on the threads.

One is now free to install the rear sprocket. Conical spacer, rear sprocket, washer then sprocket nut are installed on the rear axle. Torque for the sprocket nut is specified with the threads greased with Retinax HDX2, or Castrol LMM as I used in this case.



Torque this bad boy up to 156 Nm. Get a friend to hold the rear brake on so the rear axle doesn't turn.



Once the proper torque is reached, check to see if you can put the retaining pin on the rear nut. One end (the longer end) goes into one of the two holes in the axle. If you cannot get it into one of these two holes, TIGHTEN the nut up until you can get it into the closest hole. Never, ever, ever loosen the nut from the specified torque to get the safety pin in. For added safety, cable tie the ends of the safety pin together once you have installed it correctly.

Tension up the chain using a C-spanner, and install the pinch bolts into the swingarm. Pinch bolts are torqued up with Retinax HDX2/Castrol LMM on the threads and under their heads, to 33 Nm. Torque the left bolt, then the right, then re-torque the left bolt. This is referred to as 'Sequence 1-2-1' in the workshop manual. If you feel like it, you can torque up the right, then the left, then the right, but in either case, you have to torque up the one you do first after you have torqued up the second one.

I also like to do this in two stages, say to about 20 Nm in sequence 1-2-1, then 33 Nm in sequence 1-2-1. But I'm fastidious like this.

Now you install the rear wheel. Be very, very careful with this part.

Note the drive dogs/pins on the rear axle.



These go into holes cast into the rear wheel.



It is very easy to put the drive dogs into the channels on the rear wheel. So install the wheel carefully, and make sure you cannot spin it with the rear brake on except for the teeny tiny amount of play that is inherent in the design.

With that done, install the conical washer on the wheel side, then the rear wheel washer, then the rear wheel nut.

The rear wheel nut is torqued to 176 Nm, with Retinax HDX2/Castrol LMM on the threads. Torque it up to this, then, install the safety pin. Again, if you cannot install the long end of the safety pin into either of the two holes in the rear axle, tighten the nut slightly until you can install it into the closest of the two holes. Cable tie the ends of the pin together to make sure it can't pop off.

With that, take the bike for a test ride, park it in an awkward spot, and take a photo to prove the whole thing is back together.



Now go have a beer. You've earned it!
« Last Edit: February 16, 2010, 04:49:53 AM by ellingly » Logged

Team Ghetto Racing: motorcycle racing and riding on a budget
2006 Ducati MS2R1000 road | 1973 Suzuki GT250 cafe race | 1982 Yamaha RD250LC race | 1991 Suzuki GSXR750 perpetual project | 1984 Suzuki TS250x vintage enduro | 1997 Honda CT110 postie of death | 1982 Kawasaki KH100 bucket racer
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