Steering Stem Bearings

Desmo_Demon · Post by **Desmo_Demon** » Wed Jan 24, 2007 4:17 pm

I'm in the process of changing out the steering stem bearings on my '87 Paso and wanted to share the info that I ran across.

What appears to be the original bearings on my bike are taper-roller bearings of SKF manufacture. The bearings are an odd-size and don't cross reference with much of anything else, and I've found them to range in price from $16-$25 USD each.

Bearing - SKF #32005-X/Q
Measurements - 25mm id x 47mm od x 15mm width

I just wanted to share this info to try save others from having to do the research.

Garnet · Post by **Garnet** » Wed Jan 24, 2007 8:48 pm

I just checked my current SKF price list (Canada) and 32005-XVB is the current number for that size. It seems to be readily available and price is around 25-32 $CDN.
Good Luck
Garnet

Desmo_Demon · Post by **Desmo_Demon** » Wed Jan 24, 2007 9:04 pm

Garnet wrote:I just checked my current SKF price list (Canada) and 32005-XVB is the current number for that size. It seems to be readily available and price is around 25-32 $CDN.

I just picked up a pair about two weeks ago with the above SKF number (ending in "X/Q"), in the USA. I found them locally for $17 USD each. There was one on eBay a few weeks ago for $10, but he only had one.

The part number that I bought is listed here, from the SKF USA site:

http://www.skf.com/skf/productcatalogue ... ame=1_14_1

I was told that the suffix code is a difference in bearing tolerance, or something to that effect.

Desmo_Demon · Post by **Desmo_Demon** » Mon Jan 29, 2007 7:57 pm

I went to assemble the front end on my Paso, and not suprisingly, I realized that the previous owner didn't put it together correctly.

There is a seal in the top and bottom of the steering head, and neither seal was there (seal is part #937817081). Turns out that seal is obsolete, now. Here is the size of that seal...

45mm ID x 52mm OD x 2mm thick

I've been calling a lot of the Ducati dealers in the USA, have a guy checking with a dealer or two in Italy for me, and I've contacted a huge dealer in Australia and am awaiting a response. The closest I can find anywhere else is a 45x52x7. Anyone know where I can get this seal? I need two of them.

More data:

Note - There is a "distance piece" (part #037037020) which is a spacer and has a groove in the ID for an o-ring. This o-ring (part #46320046A) is also obsolete. Fortunately, it is a fairly standard metric o-ring and can be found in many places. I believe the measurements for this o-ring are 2mm thick with an ID of 24mm. I found them available through McMaster-Carr.

Garnet · Post by **Garnet** » Tue Jan 30, 2007 4:09 pm

CR seals (SKF) list a 45 x 52 x 4 as part # 17692. A bit closer....

Desmo_Demon · Post by **Desmo_Demon** » Tue Jan 30, 2007 5:53 pm

Garnet wrote:CR seals (SKF) list a 45 x 52 x 4 as part # 17692. A bit closer....

Those will probably work. The worse that I may have to do is place a 1-2mm spacer between the distance piece (spacer) and the bearing. You have a link for this listing? I can't find that anywhere on the USA website for SKF. Thanks!

Desmo_Demon · Post by **Desmo_Demon** » Mon Feb 05, 2007 6:55 pm

I found a 45mm id x 52mm od x 4mm thickness seal through...

http://www.metric-seals.com/

They are a little under $7 each, so I'm going to try these. I think the recession in the steering head is right at 4mm, so, if the lip of the seal aligns with the distance piece (spacer) correctly, I will be able to use that....and put this front end back together!

Desmo_Demon · Post by **Desmo_Demon** » Thu Feb 08, 2007 2:15 pm

I got the seals in yesterday. The lip in the steering head where they are installed is 4mm deep and the seal's lip is low in the seal, so they worked wonderfully. I have the bearings and races, seals, and the lower triple with stem now installed on the bike. All I need, now, is some time to put the rest of the front end together.

The seal on http://www.metric-seals.com is listed as part #S 45 X 52 X 4 WAO. They cost me $6.90 each and a whopping $8 in shipping via UPS in the USA. I hope this helps someone in the future.

lceriani · Post by **lceriani** » Mon Apr 23, 2007 9:33 pm

I am in trouble with steering bearings, too... I disassembled mine, but I cannot recognize the manual scheme.

I found that the whole assembly should be like this:

Where:
2: #036191020 = washer
3: #762604606 = bearing (SKF #32005-X/Q)
4: #037037020 = distance piece
5: #937817081 = junk ring
6: #037037030 = ring nut
7: #707006020 = screw
8: #46320346A = O-Ring

I read that:
- bearing (3) should be SKF #32005-X/Q (X=ISO dimensions, Q=special geometry)
- the distance piece (4) has a inner groove for O-R (8), that should be a standard and easy replaceable component
- the "junk ring" (5), that you call "seal", seems difficult to find, but you replaced it with a 45mm id x 52mm od x 4mm

So my questions:

- is the bearing a unique component or can it be split in two pieces? is that the SKF bearing you used? http://www.skf.com/skf/productcatalogue ... 1310002005
I only could extract the "cage" with rollers, but not its "seat" (the external part), that seems very stuck. Is this correct? Should I force and push the blocked seat with a tool to remove it or could I re-use it again?

- what about the washer (2)? I cannot see if I have washer because I cannot fully remove the bearing, but in case they are missing, do you know their dimensions?

- does the seal you bought perfectly fit?

Thanks!
LC

Post by **paso750** » Mon Apr 23, 2007 9:57 pm

- is the bearing a unique component or can it be split in two pieces? ... I only could extract the "cage" with rollers, but not its "seat" (the external part), that seems very stuck. Is this correct?

You`re answering your own questions. Yes the bearing is split in 2 parts. The washer you cannot seem to find is below the bearing seat that is still in your steering coloumn.
If you can clean the bearing seat and it looks ok you may leave it, but normally it`s recommended to replace the complete bearing.
To remove the seat and the washer I spayed some oil in there and then used a wooden stick (soft, not hardwood) and a hammer to drive it out slowely. If you do that and if you think about reusing the seat don`t hammer on one spot but do it on different points until it comes out.

just look at desmos bearing seat to see how it should not look like if you intend to reuse it

ducapaso · Post by **ducapaso** » Mon Apr 23, 2007 10:14 pm

Anyway, they sell the entire bearing, so, you'd surely bettter taking away the external ring

lceriani · Post by **lceriani** » Tue Apr 24, 2007 2:33 pm

I would like to paint the body, do you think it's better to remove (and replace) the entire bearing or to leave and cover it?

Post by **paso750** » Tue Apr 24, 2007 2:48 pm

frame or body ?
If it`s the frame it`s better to remove the bearings. You`ll need to sand the frame or glas bead blast it and you hardly can ensure that there will be no dust getting in the bearings if you just cover them.

Desmo_Demon · Post by **Desmo_Demon** » Tue Apr 24, 2007 3:18 pm

Looks like paso750 answered your questions on the bearings, but I'll also state that the bearings typically are sold as a matched set of the cage and race together. Sometimes, you can buy them separate, but it is always recommended to replace them as a set. If one part is worn and you replace the other part with a new one, it is often stated that premature failure of the new part can occur.

To remove the race (it is press-fit into the frame - similar to wheel bearings), I used a huge Phillips-head ( + ) screwdriver and drove the race and washer out from the opposite side....that is, I stuck the screwdriver through the opening at the top of the frame to drive the bottom bearing race out. As previously mentioned, you want to "walk" the race out by moving the punch (the item you are hitting to drive it out) to different spots on the race. This will also prevent the race from getting cocked to one side and getting wedged in the steering head. I typically will hit the race in this this order....

lceriani wrote:- does the seal you bought perfectly fit?

Yes, the 45 x 52 x 4 seal (junk ring) that I bought works very well with the steering head. I have not seen any signs that it will not remain in the frame and it does not appear to be rubbing where it shouldn't.

If you can find a way to safely remove the original seals, you may be able to salvage them, but I have no advice on this. I have two spare frames that still have the original seals in them, and I have yet to see if I can remove them without damaging them.

The previous owner of my bike tried to remove them and tore the seal from the metal ring section of the seal. The metal part was difficult to remove from the frame by itself. Here, you can see where I was barely able to catch the metal ring to start removing it from the frame.

I have been told that a lot of older motorcycles never had a seal, so dirt and water was able to get to the bearings fairly easily. This made replacing of the bearings more of a regular maintenance item (every few years?), but if we can prevent having to change them too often, the better!

Here is the new seal with the bearing installed under it....

Here is the new seal with the distance piece (spacer) and bearing installed....

paso750 wrote:If it`s the frame it`s better to remove the bearings. You`ll need to sand the frame or glas bead blast it and you hardly can ensure that there will be no dust getting in the bearings if you just cover them.

If you are going through the trouble to disassemble the bike, you'd probably be better off to just replace the bearings so you won't have to worry about going through the hassel of removing the forks and triple clamps to change them later if they happen to go bad.

I've known of some people to take the cage section out while leaving the race in the frame. Then, you either have to cover the races or put wheel bearing grease on them before painting. If you coat the race with bearing grease, the paint will not stick to the race and it is really easy to remove the grease and paint from it when the paint has cured. Vinyl tape, such as electrical tape, is pretty good for masking, as it is bendable and doesn't leave much of a sticky residual when you remove it.

Post by **paso750** » Tue Apr 24, 2007 7:05 pm

The previous owner of my bike tried to remove them and tore the seal from the metal ring section of the seal.

So it`s probably better to try to drive out the washer and the race also when you want to remove the seal because if you do that the seal will come out for sure and things like these can`t happen.