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rear bearings and brake

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28 minutes ago, Lucky Phil said:

Yes docc all the bearing should have pretty much identical dimensions as they are made to a standard. I was a little perplexed when you mentioned they were different. The calipers are accurate enough for this type of measuring.

The mission is at the end of the day to minimize the lateral clamping force by the axle nut on the inner races as much as is possible. Ball bearings can tolerate some lateral load but its not their primary load path. Ducati main bearings on my engines for example are ball bearings BUT they are Angular contact type to cope with the lateral loads caused by the clamping effect of the crankcases when the engine is cold and the side thrust form those engines fitted with helical primary gears. 

My advise is to either machine up a new spacer which to someone like Chuck for instance would be a doddle or do as I did and add a shim to the spacer to bring it up to the correct dimension. I went the shim route because I could do it with a single shim I had on hand and I didnt have any raw stock that would be suitable at the time. I also rarely remove my wheel so the spacer falling out wouldnt be an issue. I bonded it to the spacer. When the bearings are fitted and the spacer is the correct length it also doesnt float around when the wheel is out like a short spacer.

The sleeve on the right side always tends to corrode anyway but any spacer in this application and the one on the other side of the rear drive thats made of steel ( which is all of them from  memory) shouldn't really suffer from any crush by whats produced from the axle being torqued up.

Ciao   

The fourth spacer is inside the reardrive.  I really do not want to open up another reardrive unless I absolutely have to.

Seems the rear axle carries five bearings, four spacers, and three "forks" (two of the swingarm and one for the brake bracket) . . . busy axle, as I said!

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3 hours ago, docc said:

The fourth spacer is inside the reardrive.  I really do not want to open up another reardrive unless I absolutely have to.

Seems the rear axle carries five bearings, four spacers, and three "forks" (two of the swingarm and one for the brake bracket) . . . busy axle, as I said!

Yes docc dont bother going inside the drive unit. There's a lot of stuff going on in there, and one of the reasons I consider that these days shaft drive is a waste of time. I'd rather turn the drive through 90 deg in the gearbox and run an oring chain and live with a bit of simple lubrication every 6-800klms. Just think, you can renew your whole final drive assembly when its worn out in a few hours on a Saturday afternoon having a couple of beers and watching the game of your choice for maybe $200 odd bucks.

 

Ciao 

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On 4/22/2019 at 12:49 AM, gstallons said:

Buddy , with bearings now . I don't know which brand is best .  I would buy SKF deep groove bearings . I used to have that info in the basket next to me but..... 

Just make sure it is not Made in China . Everything from chewing gum to dog food is made there now . UGH !

From Google:
 
Currently, SKF China has 18 manufacturing sites in China (including PEER), with products ranging from various types of bearings, seals, lubricants and mechatronic products, etc.

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Still waiting on new bearings (Koyo C3) and new spacers (from Italy). Radial play in the reardrive pinion has been suspect, so when the rabbit hole opened up I , of course, dove in  . . .

IMG_8827.jpg

I asked the other inmates on the ward if this was a form of insanity and they all assured me: I ain't broke, "jus' badly twisted." :blink:

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It is good to know who is having spare parts.  Only SKF  6204 sealed made in Bulgaria was available,, but will install a 1mm bushing for no play on the bevel side.

cheers tom.

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25 minutes ago, Tomchri said:

It is good to know who is having spare parts.  Only SKF  6204 sealed made in Bulgaria was available,, but will install a 1mm bushing for no play on the bevel side.

cheers tom.

Yeah, hoping the internal spacer (coming from Italy) is the correct 113mm. Otherwise, I will shim and hope the next new bearings hold up . . .

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9 minutes ago, docc said:

Yeah, hoping the internal spacer (coming from Italy) is the correct 113mm. Otherwise, I will shim and hope the next new bearings hold up . . .

Radial play on the outer input shaft bearing is normal Docc, you can't eliminate it unless it's originating from the small inner "nose bearing" on the pinion. 

Ciao

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57 minutes ago, Lucky Phil said:

Radial play on the outer input shaft bearing is normal Docc, you can't eliminate it unless it's originating from the small inner "nose bearing" on the pinion. 

Ciao

How much is acceptable? When the Sport started *clacking and *clicking and *popping in the mountains, the radial play on the pinion gave concern.

The "green" 50,000 mile reardrive has about 0.012" and the original 111,000 miler feels like more, but the best measure I get is ~0.014".

The two replacements (8,700 miles and 14,000 miles) have no palpable radial play.

All the popping noises still appear to be from played-up (new) wheel bearings. Still working on a solution for that . . .  :(

Stacked tolerances? :huh2:

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6 hours ago, docc said:

How much is acceptable? When the Sport started *clacking and *clicking and *popping in the mountains, the radial play on the pinion gave concern.

The "green" 50,000 mile reardrive has about 0.012" and the original 111,000 miler feels like more, but the best measure I get is ~0.014".

The two replacements (8,700 miles and 14,000 miles) have no palpable radial play.

All the popping noises still appear to be from played-up (new) wheel bearings. Still working on a solution for that . . .  :(

Stacked tolerances? :huh2:

Both of my bevel boxes have radial play. I don't like it but it doesn't seem to be an issue. It's also easy to mistake play in the outer bearing with wear in the small inner. There is a technique to distinguish the two I posted a few years ago. 

you can't really use the lock ring to eliminate the play either by tightening. 

I found when my rear wheel bearing badly worn I had a clatter feel through the footpeg with the throttle in a float setting. Power on and in the overrun was ok.

ciao

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I feel like the most recent replacement reardrive is a solid piece and cleaning up nicely. It has almost 100,000 miles less than my original. It appears the bit of radial play in my original reardrive was not a contributor to the wheel bearing failures.

Still, I have no closure on why those SKF wheel bearings played up. I am having quite a time studying spacers and rear axles. Puzzling!

image.png

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