Bearing question.

[1500Rider]

I recently had a front wheel bearing go on my '97 Tourer. After pulling the bearings (6004-2RS) I discovered that the bearing seats had been badly damaged by one of the previous owners of the bike during a previous bearing change. They were so far gone that I needed a new front wheel. As such, I ordered a set of new chrome wheels from Chrome Pros. I decided to order a set of '99 wheels to take advantage of the larger bearings in the front wheel that '98 and newer Valkyries have. As they had a sale on on the installation of bearings and spacers, I decided to take advantage of it.

I received the wheels today and upon inspection noted that the dust seals where not included in the special. This was probably a good thing. I decided to check the bearings to ensure that I had received '99 wheels and not '97. Despite Chrome Pros assurance that OEM bearings would be used, I found a brand of bearing I'm not familiar with installed (could be OEM, I don't know). The front bearings were Nachi 20BCS21NSE. When looking up the specs to see if they were the same as the 6204-2RS bearings that should be installed, I discovered that all measurements were the same except for the inner diameter. The called for 6204-2RS bearings are supposed to have an inside diameter of 20mm. The specs for the Nachi bearings says they are 22mm.

Right away I assumed they were the wrong bearings. I slid the axle through the bearings and there was very little slop. I decided to try the axle on the old '97 bearings, also with an inside diameter of 20mm. They felt about the same as the Nachi.

Now, here's where things get strange. I decided to measure the old bearings and new bearings expecting to find a measurement of 20mm and 22mm respectively. What I found instead are that both bearings measure 21mm inside diameter.

My question is, do different bearing manufacturers have different standards when it comes to bearing measurements? Are the Nachi bearings I have installed now comparable to the 6204-2RS that Honda specifies? With the axle installed through the new bearings there doesn't appear to be any slop in the system. Unfortunately, with winter fast approaching and the bike off the road right now, I have no way of testing.

Interested in opinions from those who know more about bearings than I do.

[saab9k]

bearings has a standard base ##. Called a manufacturing standard ##

For marketing ( selling ) there can be different numbers. Kind like oil filters. ! filter can 50 or more different # on them depending on who sells them.

[1500Rider]

I'm less concerned about the naming terminology but I am concerned that the stated specifications for the inside diameter are, at least on paper, different. I don't know if some manufacturers allow for such a large variance. One is 1mm larger than the inside diameter specification while the other is 1mm smaller. Both measure at 21mm.

I'd rather not take a chance risking bearing failure without knowing whether these two bearings are comparable or not. I read in another post of an owner who said one of his rear bearings was the same Nachi and came that way from the factory. That bearing was also specified by Honda as a 6204-2RS. This leads me to believe that they are, in fact, the same bearings, however, every other site where I've found both bearings listed clearly differentiates the two bearings as for being for different applications (i.e. bikes). The Nachi bearings I have installed are only listed as being used by Honda on the CBR600RR for 2003 and several subsequent years. The Honda part numbers for the Nachi bearing and 6204-2RS on the CBR600RR and Valkyrie are different as well.

Any ideas?

[Ricky-D]

I feel you are over thinking this issue.

The bearings will be fine and there will be no catastrophic issues.

The item you should be concerned with is whether or not the spacer is inside the wheel.

***

[F6Dave]

Why not just get some calipers and compare it with another 6204-2RS?  Even if you have to buy one, they're not expensive and it doesn't hurt to have a spare around.

[1500Rider]

Spacer is installed although I did notice the bearings are not seated all the way.

Thanks for the suggestion F6Dave. Good idea. Think I'll do that.

Still don't know why they'd install a bearing that, according to specs, is not correct. Maybe their database has some wrong information or the two bearings are interchangeable. Would feel better if I knew for sure.

[salty1]

Have you taken this whole issue up with Chrome Pros? Seems to me they should be able to explain this away, if not, give them their wheels back.

[1500Rider]

Will be contacting them directly to see about the bearing issue as well as some other concerns. Just wanted to see what others had to say to see if I was incorrect in my assumption that the bearing were wrong.

[Smokinjoe-VRCCDS#0005]

You got a picture of this Chrome Pro wheel ?

[1500Rider]

Not yet. Going to polish them up this weekend and continue researching if the bearings that are installed are an acceptable replacement for bearings that are supposed to be in there.

As for pictures, never posted any to this site and am not sure of exactly how. Will have to look into that too.

[Rio Wil]

I would be curious as to the diameter of your axle shaft in inches,,,ie, .788  .

Why do you think the bearings are not seated all the way....is there a lot of slack in the center spacer?