Rear wheel assembly bearings

[DerBrizon]

I need to replace all wheel bearings in my Strada. The rear is shot and was an emergency coming home today. the front I'll probably do for good measure.

I bought 6203 bearings - there are four at a smaller asize and two at a larger size. I have the smaller size bearings on hand.

The larger size bearings I'm unsure. Anyone know the dimension of the larger bearings? I found this: 20 x 47 x 14 6204-2RS1/C3. Correct?

The F650 Dakar and G650 have the same hubs, yes? So is this information correct: For the record, F650GS & Dakar wheel bearing part No's and sizes

Mfr BMW Part No Description Size Mfr Part No

SKF 07 11 9 981 221 Chain Carrier - (x2) 20 x 47 x 14 6204-2RS1/C3
SKF 31 42 2 314 724 Rear Wheel - (x2) 17 x 40 x 12 6203-2RS1
SKF 31 42 2 314 724 Front Wheel - (x2) 17 x 40 x 12 6203-2RS1

F650GS & Dakar seals

Seals
CFW 07 11 9 965 056 Chain Carrier 30 x 40 x 7 BAFUD2SL1X7
CFW 07 11 9 965 056 Rear Wheel - LHS - 30 x 40 x 7 BAFUD2SL1X7
CFW 07 11 9 902 384 Front Wheel 25 x 40 x 7

All the above bearings & seals available from your local bearing supplier and in Oz the prices are 1/3 of the price from BMW

There is also a list at F650.com which from memory has part No's for NTN & NSK as well as the SKF no's above

If not I'd appreciate it if someone could help me find the right stuff to get.

meanwhile is there a specific bearing puller anyone recommends using to get these things out? there's no lip to bite with a drift so I can't hammer them out.

 

[glitch_oz]

Also it has been mentioned the bearings are on the small side. So buy quality.

For the rear wheel, they are.

I need to replace all wheel bearings in my Strada. The rear is shot and was an emergency coming home today. the front I'll probably do for good measure.

I bought 6203 bearings - there are four at a smaller asize and two at a larger size. I have the smaller size bearings on hand.

The larger size bearings I'm unsure. Anyone know the dimension of the larger bearings? I found this: 20 x 47 x 14 6204-2RS1/C3. Correct?


If not I'd appreciate it if someone could help me find the right stuff to get.

meanwhile is there a specific bearing puller anyone recommends using to get these things out? there's no lip to bite with a drift so I can't hammer them out.

Your quoted table is correct.
You'll need
2 bearings each for the front wheel 6203
2 bearings each for the rear wheel 6203
2 bearings for the sprocket carrier 6204
plus the seals as quoted.

Just don't replace the OEM bearings with the same "made in Portugal" junk-SKF's Explorers.

Here's something about the sprocket carrier

 

[duibhceK]

I found this: 20 x 47 x 14 6204-2RS1/C3. Correct?

the bearing I removed from my sprocket carrier earlier this week was : SKF Explorer part # 6204-2RSH/C3.
I ended up replacing it with a Timken alternative (6204-2RS). I did opt for a non-C3 version as the C3 is described as having more free play for use in high speed / high heat environments, which a motorcycle wheel is neither.
C3 bearings are used all over for motorcycle wheels with with little issues, but since the sprocket carrier bearing on the TR, Dakar and Sertao seems to be a particular weak spot I figured I'd give this one a go. Time will tell whether it makes a difference.

I did have a bit more trouble with removing the old bearings than HF did. I have the same bearing removal tool, but those bearings were in there very tight. Took me 2,5h to get everything out. Most of that time was spent on getting that first bearing out. The second one can be more easily tapped out from the other side (after removing the retaining clip obviously).

 

[DerBrizon]

Great. I'm going to have a lot of trouble. One of the bearings in the hub fell apart and just the outer ring is stuck in there. I'm off to the store to find tools that can help. :\

Thank you for the help, everyone.

 

[DerBrizon]

Also, I had no intention of going OEM on any of the parts. 15k miles and one is failing and another completely fragged - terrible.

 

[Johnn]

Heaps of advice on this thread.
http://www.bikechatforums.com/viewtopic.php?t=247023

When I couldn't move the my inner bearing , I heated the carrier in an oven at about 100c for fifteen minutes. Light tap and it fell out. Removed the cir-clip and the outer one was tapped through.

I tightened a dyna bolt of the correct size (Local bolt shop has them at 2mm increments) into the middle of the bearing and tapped on that. You could also use it as a puller if you have the right bits of packing. ( I didn't).
A very cheap solution if you don't required a bearing puller on a regular basis.

I ground down the diameter of the old bearings on a bench grinder and used them to install the new bearings fresh from the freezer.

 

[Geeza]

Make sure when changing the 6204 bearings in the sprocket carrier you use ones with a C3 tolerance, not sure why this tolerance is specified but from my understanding that is what is needed.

 

[duibhceK]

Make sure when changing the 6204 bearings in the sprocket carrier you use ones with a C3 tolerance, not sure why this tolerance is specified but from my understanding that is what is needed.

I am not at all convinced that is the case. As mentioned above, when my sprocket carrier bearings failed I deliberately chose to replace them with the non-C3 counterparts.

I ended up replacing it with a Timken alternative (6204-2RS). I did opt for a non-C3 version as the C3 is described as having more free play for use in high speed / high heat environments, which a motorcycle wheel is neither.
C3 bearings are used all over for motorcycle wheels with little issues, but since the sprocket carrier bearing on the TR, Dakar and Sertao seems to be a particular weak spot I figured I'd give this one a go. Time will tell whether it makes a difference.

I'm hoping the non-C3 bearings will last a little longer.

 

[dmw_az]

How many miles are you guys getting on your bearings? What can one expect on a Terra that sees mostly street duty?

 

[hasenpfeffer]

Seems hit and miss. I'd recommend checking them during chain maintenance. Could last a while, but some are finding they don't last long.

 

[duibhceK]

Seems hit and miss. I'd recommend checking them during chain maintenance. Could last a while, but some are finding they don't last long.

It took +- 30,000km before they started acting up on both our Terras. With ours and others that I've seen on here and Sertaos that I've read about it seems to be mainly the outer bearing on the sprocket carrier that fails first. Keep an eye on that especially. The wheel bearings seem to last a lot longer as long as that sprocket carrier bearing stays healthy.

 

[Geeza]

Selecting Bearing Clearance (General guidelines)
Clearance fit on both inner and outer ring. Low to no axial loading. No preload. Low speeds. Little tolerance for play. Low temperature. C2
Low torque. Standard loads. Light preload. Slight interference fit on inner or outer ring, not both. Low to medium speeds. Average temperature. CN
Very low torque. High loads. Heavy interference fits. High temperature. Preloaded. C3,C4,C5

Understand the reason to not use the C3 as previous ones have failed, just curious to know what level of interference fit the bearings are in the carrier.
Also In replacing mine I looked specifically for Japanese made bearings, have noted over the years a lot of Japanese bearing manufacturers are making bearings outside of Japan and have experince with these previously reliable brands failing.

 

[snail_72]

I have just done my bearings when i replaced the tiers, 1200km all where good apart the back wheel hub. but really pay $150 + for just one new tire front or back and just $40 or so for all new bearing front and back. I brought what they had my bearing shop NSK's, i pulled off the bearing seals and packed them full of bearing grease. New tries and bearing $430 AU. and took an extra 2 hours for the bearing replacement. I will check them next time i replace my tires.

 

[MotocycleWriter]

Make sure when changing the 6204 bearings in the sprocket carrier you use ones with a C3 tolerance, not sure why this tolerance is specified but from my understanding that is what is needed.

C3 isn't tolerance, it is clearance. Tolerance, clearance, and fit are independent. This helped me understand the issue: Clearance and Preload

So, C3 is an internal clearance, meaning a 'gap' between the ball and the inside of the race. Given an interference fit, the race is slightly compressed. If the clearance is too small, as in a C0, the compression of the outer race can result in the preload on the bearing being higher than specified. Choosing a larger clearance can allow you to use a tighter interference fit.

This may be the principle at work here so going with a C0 might result in too much preload. I have no idea if that will be a problem. Just conjecture from reading about the specs.

 

[engineerk9]

the bearing I removed from my sprocket carrier earlier this week was : SKF Explorer part # 6204-2RSH/C3.
I ended up replacing it with a Timken alternative (6204-2RS). I did opt for a non-C3 version as the C3 is described as having more free play for use in high speed / high heat environments, which a motorcycle wheel is neither.
C3 bearings are used all over for motorcycle wheels with with little issues, but since the sprocket carrier bearing on the TR, Dakar and Sertao seems to be a particular weak spot I figured I'd give this one a go. Time will tell whether it makes a difference.

I did have a bit more trouble with removing the old bearings than HF did. I have the same bearing removal tool, but those bearings were in there very tight. Took me 2,5h to get everything out. Most of that time was spent on getting that first bearing out. The second one can be more easily tapped out from the other side (after removing the retaining clip obviously).

Carefull use of a hot air gun, to expand the alluminium sees the bearing fall out

& in again

I suggest gently remove the inner seal, add a little more good quaility grease then replace the seal

Also, put the bearings in the freezer for an hour or so before fitting, heat the hub, the bearings will either drop in or just need a firm push

 

[duibhceK]

Carefull use of a hot air gun, to expand the alluminium sees the bearing fall out

Tried that, it was still a royal PITA to get that first bearing out.

Also, put the bearings in the freezer for an hour or so before fitting, heat the hub, the bearings will either drop in or just need a firm push

Yes, did that as well. Installation was a breeze.

 

[duibhceK]

So, C3 is an internal clearance, meaning a 'gap' between the ball and the inside of the race.
[...]
This may be the principle at work here so going with a C0 might result in too much preload. I have no idea if that will be a problem. Just conjecture from reading about the specs.

Exactly. But without actually trying it, it is hard to tell whether that poses problems. Another conjecture could be that the extra play in a C3 leads to premature wear and eventually failure... I now have new C0 bearings in my bike and new C3 bearings in my GF's. We ride together most of the time so we'll see whether it makes any difference.
In any case the results will determine which bearings I'll be bringing as spares on our Siberia trip next year.

 

[MotocycleWriter]

So was there a decision on which brand of bearings are preferable to SKF and where to get said bearings?

 

[Geeza]

Nachi bearings.

 

[glitch_oz]

Nachi bearings.

As long as they're Jap-made!
There'll be other options in different markets.