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Uly_man
| | Posted on Thursday, June 07, 2012 - 02:09 pm: | 
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"Uly_man, please tell me you agree with all of this. I know you are an engineer and I only wish I was. Thanks."
Yes and no. Thats because there are so many factors involved and the reason it is still an issue. I do not see any reason that pressing in a bearing without pushing on the inner ring would be a problem and is normal bearing install practice.
I would say this, it is normal bike running practice and always has been.
Unlike many things in this world you need the LISTEN and FEEL what your bike is doing/telling you. This is what biking is all about and the reason it is so good. |
Motorbike
| | Posted on Thursday, June 07, 2012 - 02:53 pm: |
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I do not see any reason that pressing in a bearing without pushing on the inner ring would be a problem and is normal bearing install practice.
Normally this is not an issue. In fact you can press the first bearing (rotor side) into the wheel by only pressing the outer race until it seats in the wheel. But, I assume a lot of people think that you press the next bearing in until the outer race seats in the wheel too. That is wrong. To do this right, you must support the inner and outer races of the first bearing while you push the next bearing in until the inner race touches the spacer. I will stand by this theory until the day I die. I'm sure Al Lighton, whom most of us respect for his Buell and mechanical knowledge, would agree with me. |
Nobuell
| | Posted on Thursday, June 07, 2012 - 06:22 pm: |
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Motor
You brought up a valid point worth considering. The first bearing is seated against the stop. The second bearing is pressed in to match up to the spacer/inner race. Possibly, the stops machined into the wheel stop the second bearing prior to the proper race load is achieved. This could place a substantial side load on the bearing and could explain why failures are all over the map mileage wise. It would be a simple matter to measure a fresh spacer and verify that the distance between stops are less than the spacer length. Stop distances that exceed the spacer length could introduce an additional failure mode.
Regarding belt tension - I posted an extensive discussion on belt tension last year. The measured tension of a newly installed belt greatly exceeded the manufacturers specification. I adjusted the pulley slot to reduce belt tension to the manufactures standard. Running tight belts could be one more failure mode to be introduced. Once again, the design, assembly methods, bearing shield design and luck all contribute to the failure of a marginal design.
I have had my 2010 installed for approximately 20K miles. I recently had the wheels off for new tires. I inspected the bearings and found them to be silky smooth with no signs of internal moisture. The bearings externals were clean with no signs of rust. The spacer was still positioned correctly. All in all, it looked like I would except them to look. I did reduce the belt tension to the manufacturers standard and reduced the axle torque somewhat. Does that contribute to more reliable operation? Who knows! One thing for sure, the new wheel designs is much more robust than the original and that has to help.
My current concern are the rear bearings on my recently purchased 2008 1125R. I have not read about failures to the extent of the Ulys. Should I bit the bullet and replace my purrdy blue rear wheel with the available black 2010 version or watch closely for signs of failure? |
Etennuly
| | Posted on Thursday, June 07, 2012 - 11:27 pm: |
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I have replaced several of these bearings now. My contention is that the fittment engineering is sound. The spacer is working correctly when the bearings are properly installed.
I feel that the bearings are near under rated for the bike, or at the bearing's maximum load for what is needed, and a near total lack of grease is what is killing them.
I have found in a couple of the bearings that I pulled the seals on, so little grease that to spit on them would be doing them a favor. No matter how good a bearing is made a lack of lubrication will kill them. Add in a tiny amount of grit with the lack of grease reserves and they will eat themselves up.
Why the hell do we not have tapered roller bearings for these load pressures? |
Uly_man
| | Posted on Friday, June 08, 2012 - 12:24 pm: |
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Motorbike - "Normally this is not an issue. In fact you can press the first bearing (rotor side) into the wheel by only pressing the outer race until it seats in the wheel. But, I assume a lot of people think that you press the next bearing in until the outer race seats in the wheel too. That is wrong. To do this right, you must support the inner and outer races of the first bearing while you push the next bearing in until the inner race touches the spacer." Yes that is correct.
"Stop distances that exceed the spacer length could introduce an additional failure mode." Both ways will do this.
"Regarding belt tension - I posted an extensive discussion on belt tension last year. The measured tension of a newly installed belt greatly exceeded the manufacturers specification." I have not read it but? The last belt version is VERY much tighter and stiffer than the early ones. Also consider this one. As the bike heats up the belt gets tighter. Or at least it did on my 06 bike which got VERY hot all the time. I can only assume that was because the heat of the oil in the swing arm made the arm expand length ways but it is something else that would not help. I only found this by accident but proved it. The belt went from slack to quite tight. This with the arc problem of the arm is just asking for problems.
"I feel that the bearings are near under rated for the bike, or at the bearing's maximum load for what is needed, and a near total lack of grease is what is killing them." It is true to say that high torque of this bike is going to be hard on the bearings and that the larger double drive side bearings of the 2010 wheel is a much better idea. However if they are not fitted right you could still have the same problems.
The fronts do not last much past 10k and still handle right, I have proved this, and many new bikes have not been right on wheel bearings either. I have had two Ulys and they both needed bearings at 5k which is not normal to me so something was not right from the factory? Any bearings I fit from now on will be checked and packed with grease if needed. I will also now torque them up to my own spec and deal with the issues as they arise as I am not happy with many thing from HDs specs on the bike. I trust my own judgment better and am happy to pay the price if I screw it up. I have tried the HD way and now it is the highway for me.
"Why the hell do we not have tapered roller bearings for these load pressures?" Wrong type. |
Motorbike
| | Posted on Friday, June 08, 2012 - 02:05 pm: |
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I would gladly clean and re-pack my bearings regularly but, for one thing, you cannot get the bearing out and clean it properly without damaging the bearing during removal. If you only pull the outer seal to clean it, you are only doing a half-ass job. Next, I do not like the idea of using any tool to remove the seal. My thought is that the seal is a very fine piece that can be damaged easily during removal and may never seal properly when re-installed. Too bad we can't get brand new bearing seals separately, then we could just pitch the old ones and replace them during regular bearing maintenance. |
Uly_man
| | Posted on Friday, June 08, 2012 - 02:59 pm: |
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No the seals are not designed to be removed and/or refitted/replaced. On the other hand if you do this on the outer seal you will soon see if you have a leak.
We are now getting into the area of "suck it and see" so there are no engineering rules.
This is the way my Uly is going to be? I kid you not.
http://www.youtube.com/watch?v=Ctin21yrfcA |
Tootal
| | Posted on Friday, June 08, 2012 - 06:25 pm: |
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Now that was funny!!
I mentioned years ago about the distance between the stops and the width of the spacer but nobody with bad bearings has ever taken the measurement. I checked mine and it was good, the spacer was longer than the stops and I never had a bearing failure. I don't know if that's why, maybe I was just lucky! |
Xbimmer
| | Posted on Saturday, June 09, 2012 - 05:23 am: |
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If you only pull the outer seal to clean it, you are only doing a half-ass job.
Well YMMV but my half assed jobs allowed me to run my original 2006 orange sealed NTN's 50K miles, and the black sealed KBC's are at 30K+ now and performing just fine. Pop the seal, clean the contact surfaces with a soft rag, dig out exposed grease with a cotton swab, push in a couple fingertips worth of new quality grease, snap the seal back in, repeat as necessary. It's a win/win and can be accomplished in under 30 minutes per wheel at a leisurely pace. I don't understand the hesitancy factor.
Too bad we can't get brand new bearing seals separately, then we could just pitch the old ones and replace them during regular bearing maintenance.
I contacted NTN years ago when these issues surfaced. They were willing to batch sell seals but the quantities involved compared against the interest here wasn't worth it. Moot point anyway, I began greasing my bearings about 20K. Seals finally giving up toward 50K is why I changed them. Left rear bearing had rust on the outer race inside surfaces, and there was water (not much though) in the wheel hub which would explain the sidestanned exposure and resultant rust. All the rest were fine except for hardened seals.
I checked mine and it was good, the spacer was longer than the stops and I never had a bearing failure. I don't know if that's why, maybe I was just lucky!
Luck is the word IMHO. Who knows who's crushed spacers along the way to less than spec dims. I've come to believe it's the INSTALLATION of the bearings, factory or otherwise, that is suspect. I installed my black KBC's with a "kiss" onto the spacers per Al American Sport Bike and everything's been just fine for 30K+. Manually installed, with threaded rods and washers, frozen bearings, heat gunned hubs, antiseize in the bearing seats.
Oh yeah, and I believe in Treadmarks' weep holes:
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Luftkoph
| | Posted on Saturday, June 09, 2012 - 09:37 am: |
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I bought this handy little item at tractor supply,it's like a needle that has a zerk fitting, just put it on the end of your grease gun, and you can put it down inside of the bearing and pump grease in |
Uly_man
| | Posted on Sunday, June 10, 2012 - 02:50 pm: |
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I am with Xbimmer on most of this. Not sure of the reason for water in the hub. I have never had it. It might be a build up of condensation in some parts of the World. Who knows. |
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