Failure Left Rear Bearing

[Rio Wil]

OK

[X Ring]

The inner spacer in the wheel I used in my Double Row Wheel Bearing Mod article measured 4.662".  I can't tell you what year the wheel was manufactured but I can tell you it was a first design with the machining marks.

Marty

[Rio Wil]

Marty, I had a brain phart in writing this post.  The spacer you reference is the one I wanted to measure, but I measured the one in the final drive and not in the wheel.  I guess it would be interesting to determine if there is any variations in either one of these spacers. I need a couple more cups of coffee to get me going, but I don't think that a few thousands variation in the final drive spacer would put any side pressure on the wheel bearings. That one sets the distance on the splines mating and unless its so short as to cause the splines to bottom out, it wouldn't matter.  So, I am still curious as to any variation in the wheel spacer, its odd to get so many multiple bearing failures at so few miles as many have reported. I deleted the content of my original post, but to mention it again, my rear bearings are original (160K miles and the last 90K with car tires) and I changed the fronts at about 140k miles (as I remember) due to a rough bearing..

[Rio Wil]

WOW....it suddenly became clear as day...the car tire caused the failure of the front bearing...DANGER-DANGER!!!!

[Chrisj CMA]

Marty, I had a brain phart in writing this post.  The spacer you reference is the one I wanted to measure, but I measured the one in the final drive and not in the wheel.  I guess it would be interesting to determine if there is any variations in either one of these spacers. I need a couple more cups of coffee to get me going, but I don't think that a few thousands variation in the final drive spacer would put any side pressure on the wheel bearings. That one sets the distance on the splines mating and unless its so short as to cause the splines to bottom out, it wouldn't matter.  So, I am still curious as to any variation in the wheel spacer, its odd to get so many multiple bearing failures at so few miles as many have reported. I deleted the content of my original post, but to mention it again, my rear bearings are original (160K miles and the last 90K with car tires) and I changed the fronts at about 140k miles (as I remember) due to a rough bearing..

The spacers arent causeing wheel bearing failures.  The most likely cause (and this is how EVERY Honda dealer I have seen soes it) is when the bearing is tapped in flush with the wheel hup and then the dust seal is pressed in on tof of the bearing and then its installed on the bike and the bearing gets final seating by the installation process which pushes the bearing in by its inner race.  That last part is where the damage is done.

I sure hope youre not shortening them spacers.  If you go to a double roller for the left bearing you have to shorten the little top hat looking spacer that is OUTSIDE the wheel, but you dont change any of the internal spacers.

[Rio Wil]

The spacing on the outer races for the bearings is set by seating the outer races firmly in their grooves/cups upon installation. The spacing on the inner races is set by the length of the bearing spacers. If the spacer is the proper length, the inner races (and balls) will have the desired neutral side pressure bias.  The dust seal has absolutely nothing to do with this spacing or changing this spacing.  And who said anything about shortening this spacer, the question about this spacer is are they a consistent length from the manufacturer.  If they are too long or to short they will contribute to side pressure and bearing failure.  Another thought is are the bearing cups in the wheel cut to the same depth so the distance between the outer races is exactly the same when installed and fully seated.  If not then did Honda use custom spacer lengths to accommodate the variations (highly unlikely but weirder things have happened). Also, the need to change to a double row left bearing is pretty much BS in my opinion, many of us have well over 100-200K miles with no failures on original bearings and many with this mileage is with car tires as well.  So, I am looking for something more subtle as a basic cause for so many early bearing failures.   

[Ricky-D]

Just want to make a few comments on Rio Wil's post.

I agree with all you post.

There was probably a time when manufactures custom ground the inner spacer to fit each wheel, I am sure they no longer do this however.

Harley uses and intentionally short spacer and uses washer like shims to get the correct fit. This was when they were using tapered roller bearings in the wheels and the "pinch" is critical.

Now I think the machinery they use to manufacture wheels is accurate enough to allow a standard length spacer which works with all wheels that are the same. You know what I mean.

Properly, the length of the spacer should match the distance between the lands of the bore where the bearings reside.

I don't think there is really that many bearings that go bad, talking original equipment here.

Some riders like to make changing bearings a maintenance item (stupid) and other may think they've bad bearings and so to change them is top of the list.

What I want to say, is that when reading the posts over the years is is pretty clear that most bearing failure come as a result of poor mechanical practice when replacing the bearings. (yep)

Some have posted that the bearing they used for replacing the (bad) bearing turned into crap also and hasn't lasted a riding season.  What can you infer from that?  There have been reports of replacing a bearing four times.  There are many so called mechanics who have no clue regarding bearings and proper installation practices.  Some are probably working as mechanics in bike shops.

The biggest cause for failure in original bearings is contamination.

Whether it be dirt or water, contamination kills bearings.  That's why I've always dissed power washers.

A power washer is probably the worst thing to happen to motorcycles: And I'm also including those quarter machines you find at the local car wash facilities.  High pressure water will get past seals very easily.

That's what I attribute to most original bearing failures.

***

[Rio Wil]

Some are probably working as mechanics in bike shops.

================================================

I suspect you are right about the water/contamination intrusion and improper installation procedures.  Especially if one finishes seating a bearing race by driving it the rest of the way in with the dust seal..

I kept the bearings I replaced in the from wheel at 140K and just for grins clamped the rough one in a vise on the outer race. Mounted a dial caliper against the inner race and checked side to side movement...it was about .007-008 with finger pressure. Then did the same with the bearing from the other side which felt as smooth as a baby's butt.  It too, had about ,007-008 side movement..... don't know what that proves other than a bearing will have some side play that is acceptable and in our application will allow the balls to rotate in a un-biased path if the inner spacer is of the correct length.  I was a bit distressed when after installing the new bearings in the front wheel, that they felt too tight (resistance to rotating).  I gently tapped one outer race back out maybe .001-002 and it relived the resistance to turning by a considerable amount....matter of fact it felt quite nice. This kinda says the new bearings did not have the same spacing from the sides of the race as the original bearings by maybe up to .002-004 thousands. I went ahead and seated the race again and installed the wheel with the bearings a bit too tight (to my liking), it has been 20K miles so far with no ill effects noted thus. In this case, the inner races are being pushed to the outside and when installing and tightening the axle bolt it would tend to pull the inner races back together, can't imagine it would be more than .0001-.0002 or so....that spacer is not real compressible. So....just saying....I'm curious.....

[X Ring]

Some of the things I believe are the reasons for the frequency of left rear bearing replacement are 1.  improper installation and 2.  buying the cheapest bearing they can.  I've read threads where people bought bearings on price alone and that is not a good idea.  There are several variants in the 3204/5204 bearing series.  Some come with plastic cages hold the balls.  These cages aren't capable of the loads Valks put on them.  It's why I don't have a problem forking over $100 for a pair of top quality SKF bearings.  If you buy the ones Honda uses they will run you about the same price.

Marty

[2qmedic]

X Ring

You are absolutely correct on both points, and especially the quality of the bearings.

Anytime a person buys bearings outside of the manufactures parts (OEM),they should ensure the proper quality rating of the bearings. There can be the same size bearing but the quality rating can be different.  The bearing can be from the same manufacture, but they make different quality rated bearings with different operational requirements. It dosen't matter how well the bearing is installed if it is does not meet the requirements of the application.

Unfortunately, the left rear bearing is a know weak element of the Valkyrie.

Cheers  

[X Ring]

Exactlly 2qmedic!  When I was doing bearing research I discovered that the numerical designation, i.e. 3204/5204, is only a size designation.  There are several variants as far as shield and seals.  Additionally, as I have already discussed, is the use of plastic and steel ball cages.  What I haven't discussed is the grease used inside.  There are several variants in grease.  Some are suitable for light duty and low speed while others are rated for high speed/high load.  When choosing a bearing, I recommend using a bearing that someone else has investigated, such as the OEM or the SKFs that I prefer.  If you can't do that then talk with an experienced sales rep at a bearing house.  Explain your needs and they will guide you to bearings suitable for your use.  When I explained what I was using the bearings for, the sales rep told me the SKFs would probably last longer than the bike.  They were designed to be used in an industrial environment.

Marty

[MP]

I use a lot of SKF here on the farm.  Top notch bearings.

MP

[Rio Wil]

Still being curious about the bearing failures on our Valks, I took apart the only bearing failure I have (140K miles on the front wheel) just to see what the failure looks like.  This bearing had just a hint of roughness when turned by hand (with the axle inserted about 3/4 way into the race) Some of the grease had a slight brownish-red tinge that suggested rust. The grease seals were undamaged and appeared in good shape, no corrosion  or damage (other than tiny pits as seen in the picture) was noted on the bearing rolling surface of the outer race.  It is interesting to note that one side of the inner and outer race is a bit more polished (brighter) than its opposite side.  Indicates the balls circulated mostly on that side of the race.  Note the spalling/pits are primarily also on the shiny areas.  The bearing is an OEM (Nachi 20 BCS21NSE and was factory installed)

The damage to the inner race seems to me to be  not from rust but from perhaps soft spots in the race and with the balls circulating mostly over the soft areas caused the spalling (I think I am using that term correctly)  I could not see any damage to any of the balls at all and thus did not include a picture.  Did not attempt to measure the ball diameter or roundness since if these are grade 5 bearings, I don't have anything that will measure .000001......think I got enough zeros.  I have not yet opened the running mate to this bearing to see if it exhibits any evidence of an identical failure.

I wonder if this bearing would have failed if the balls were running more in the center of the inner race, seems to me the balls not only rolled radially around the race they also would spin more than normal from constant side pressure (more than encountered just during turning). So I am thinking that if a bearing is installed in a neutral state (no side pressure on the balls/races) and has a decent grease and dust shield, it should last a long time. I am running a bit of a test on this theory, as I bought a 4 pack off eBay about 3 years ago for $25 bucks and it included the double roller rear.  There was no manufacturer name, just the bearing number on the dust shield, not even a Made in China stamp.  I wanted a spare set to carry on long trips(west to east coast-Alaska, etc). Just a comment that, although I ride a lot in the rain, I never use high pressure water in washing the bike.  I wish I could remember which side of the front wheel this bearing was on..... So these $6 average cost front bearings have 20K miles and haven't destructed yet.......time will tell! 

[valkyriemc]

Interesting and a nice write up.