[jhnmltn]

Hey.
I need help with some bearing dimensions and specs.

1) The timing belt tensioner bearings.
The dimensions should be 12x32x10, correct?
I can get 6201.2RSH.C4 bearings.
Other option is 6201.2RSR.C3 by ***.
Which one would be more suitable?

2) Rear sprocket carrier bearings.
They should be 25x47x12, right?

3) Rear wheel bearings. Are they same as the sprocket carrier?

4) Front wheel bearings?
What specs etc?

I'm not really at home determining which bearings suit best.

Thanks a lot!

 

[Iwannaduc]

Hey.
I need help with some bearing dimensions and specs.

1) The timing belt tensioner bearings.
The dimensions should be 12x32x10, correct?
I can get 6201.2RSH.C4 bearings.
Other option is 6201.2RSR.C3 by ***.
Which one would be more suitable?

2) Rear sprocket carrier bearings.
They should be 25x47x12, right?

3) Rear wheel bearings. Are they same as the sprocket carrier?

4) Front wheel bearings?
What specs etc?

I'm not really at home determining which bearings suit best.

Thanks a lot!

I just went through all of this on mine. At least all but #1. I cannot remember if #2 and #3 are the same or not. I just don't remember. I got mine from Timken, which I decided upon after doing some research. The Timken bearings are rated to 20K RPM. IIRC, the SKF bearings were rated at 12K RPM. I don't know if that tells one how good of a quality the bearing is, and I don't know what RPM my wheels are turning really. However, I figure if the limitation is lower, then the quality of the bearing and the grease sealed inside of it is not as good as one rated for a higher RPM.
The page below is from when I was researching my wheel bearings and is for the rear. I just can't remember if you need 4 of these or just 2. This is for a 1993 Super Sport with the 17mm axles.
https://cad.timken.com/item/deep-gr...ection-ball-bearings--62000--63000-/62203-2rs

 

[duc96cr]

C3 is a standard clearance bearing. Unless specified otherwise, go with a C3 clearance. Seal type really isn’t any big deal, the important thing is that it’s sealed if it’s supposed to be. If you love metal seals over plastic, go with it.

 

[Iwannaduc]

I just got home from work, so I took a look through the bearings that I bought for my 900SS. Keep in mind, mine is a 1993. The later Super Sports had different sized bearings as they had larger diameter axles than the early ones. Mine are 17mm on both ends.

For my front wheel bearings I have a part number 6303-2RS
rear wheel bearings are the Timken 62203-2RS
sprocket carrier bearings are INA 6005-2RS
steering head bearings are National 07204 and 07100 for the cup and cone

The sprocket carrier bearings and wheel bearings are not the same. Hope that is of some help.....sean

 

[duc96cr]

Excellent Information. Anyone can use those part numbers to buy the equivalent bearings in any brand they choose.

 

[jhnmltn]

Hey.

I figured out what bearings I need. This will probably help someone else, too.

Tensioner bearings:
4x 6201-2RSH C3

Rear sprocket carrier:
2x 6005-2RSH C3

Front wheel:
Same as the rear sprocket carrier

Rear wheel:
2x 6303-2RSH C3

Steering head:
2x 639174

Everything except the steering head bearings (SKF does not make them anymore or something) cost me 60 euros (about 67 USD). So about 6.7$ per bearing. All bearings by SKF.

This is for a 2002 750SS i.e

 

[Iwannaduc]

Hey.
Steering head:
2x 639174

Everything except the steering head bearings (SKF does not make them anymore or something)
This is for a 2002 750SS i.e

Actually, SKF still make the bearing, the number just changed. I went to my local bearing supplier and the counter person told me they made one half but not the other. When I said that was insane, no one would make a roller bearing cone without a cup? I was told that is what their SKF interchange showed.

I then asked if the part number had changed or something, I was told no. Just no. I again said, that was insane and that I could locate the proper part on the internet. I was then told just do that then. Needless to say, after 2 decades of giving them my business, I will no longer do so.

2 minutes into my internet search I found the number had indeed changed. I forget the details but when I did further research, I found that the steering head bearing is also used in the 1950s to early 1960s Fiat 500 as a rear wheel bearing. If you search any auto-parts site with that information you can easily find them.

I think I paid around $14 or so for each cup and cone pair. $33 shipped to my door from Rock Auto. Those are the National part numbers in my last post.......sean

 

[BelgianDuc900SS]

I don't know if that tells one how good of a quality the bearing is, and I don't know what RPM my wheels are turning really. However, I figure if the limitation is lower, then the quality of the bearing and the grease sealed inside of it is not as good as one rated for a higher RPM.

Correct me if I'm wrong but I thing I once read an article about the RPM-specifications for bearings and the point was that higher RPM-bearings get hotter so they'll have some margin build in for the metal to expand. This would mean that there is no point in used higher rated bearing then what you actually need because a high RPM-bearing at low speeds will not be as good as a low RPM-bearing at the same speed. The high RPM-bearing won't get hot enough to expand to it's ideal size and will have some 'play' at low speeds.

Could this make any sense or have I been believing b*llsh*t all these years?

 

[duc96cr]

I think that yes, it makes sense but, no, it doesn’t really make any real world difference because the difference in internal clearance between the different clearance ratings is in ten thousandths of an inch and can’t be felt by normal humans. (I’m assuming you’re a normal human.)

 

[Iwannaduc]

The high RPM-bearing won't get hot enough to expand to it's ideal size and will have some 'play' at low speeds.

Could this make any sense or have I been believing b*llsh*t all these years?

Things is, RPM isn't only limited by the bearing tolerances. It is also limited by the grease used. As these are sealed bearings, it isn't like you're going to repack them later with some good quality grease.

The Timken bearing number I posted previously specifically states the RPM is a grease limiting speed. I did more research on this and found that Timken uses a high quality Mobil grease. See links below:

https://cad.timken.com/item/deep-gr...ection-ball-bearings--62000--63000-/62203-2rs

https://www.timken.com/products/timken-engineered-bearings/ball/deep-groove/

SKF uses lithium grease in this particular bearing. Lithium grease breaks down rather quickly and becomes a hard sticky paste rather than a flowing lubricant. See link below. It shows the standard lubricant for deep groove ball bearings, P/N 62203 2RS included are "MT47 or MT33" depending on the diameter. The chart below that shows the those two lubricants as lithium.
https://www.skf.com/us/products/bea...ep-groove-ball-bearings/single-row/index.html

Why SKF chose to use lithium grease rather than a high temp moly grease or even just a high quality bearing grease I don't know. I only know I don't use lithium grease for much for the reasons stated.

 

[duc96cr]

Of course , you could repack the bearings with the grease of your choice . SKF has a good reputation for making a quality product and I’m going to assume that if they used a certain grease in their bearing, with their reputation on the line, that it would be what they felt was best for the application and not some ill advised cost cutting measure. I don’t know much about grease, but I do know that what I have purchased as lithium grease is not always the same stuff. In other words, “ lithium “ grease is a category of greases and not one particular grease formula. I think it’s pretty likely that SKF used the right stuff for the application. If they had instead given a vague response that their bearings contained a specifically formulated ultra high performance grease you’d have been comfortable with that, wouldn’t you ? I try not to out think the experts. That’s why they call them expert, isn’t it ?