12-6 / 3-9 FD BearingBlues.....SOLVED

[jm1515]

First off...I must admit I don't usually stress over things like this but with all the recent FD brouhaha, here goes.....

At 39months of ownership from new and 31800mi, I've got the 12-6 / 3-9 FD BearingBlues!....
The other day, I felt a distinct buzz in the pegs as I made the hard left turn onto my street. I immediately turned into the church on the corner (ostensibly to pray ? ) and proceeded to do a bunch of tight 8s and donuts in the parking lot.
Yep...there's a buzz alright. More pronounced on left turns than rights, for some reason. The turns must be pretty tight also, or there's nothing there. I think I may have felt this once or twice in the last couple rides, but I cannot say for certain.
Got home and up on the centerstand I torqued the wheel....there's a very slight movement in both planes.
It's there...it's palpable...it's #%%@ annoying!
In the interests of complete accuracy, the 3-9 movement is not there (I think) when the FD is hot, like after a ride. Or like the 10 times or so I checked today during a ~250mi outing. Next day tho, you can def feel it. And I'm pretty sure the 3-9 movement is new (pivot bearings need tightened/replaced?), and that I have always had some 12-6 movement. The 12-6 seems to be a little looser, tho...
But the Buzz is definitely new!
Before I decided to ride it today, I changed the FD oil (Mobil1 75/90). The old stuff, if you can call oil w/ only 3700mi on it 'old', came out perfectly clean....no metal etc, just the usual fine fuzz on the magnet plug. I got a sample for BlackstoneLabs...I'm debating whether to send it.
I also took the tire off, because I had just (1300mi ago) put on new Pilot Road 2. Maybe I did not torque things down right, or maybe the PR2s hum after scuff in? Everything went back on as it should, and no sign of any leaking from anywhere. And even tho I had palpable movement in both planes, they were very, very small....so I decided to saddle up.
Sooo...is this nothing? Or the very beginning of something?
I was thinking of riding into the dealer, and being only 3 months out of warranty, perhaps getting some of this repair covered... Fat chance, eh??
If it is on the way out, how long will the big bearing take to self-destruct anyway, seeing as that I don't stunt, go off-road, and take it easy over RR tracks?
As always, any insight (consolation) is always welcomed....

[Biff's R]

The PR1 did hum at certain periods of time during it's life. Don't know about the PR2, but it could be a possibility.

[CycleRob]

"pivot bearings need tightened/replaced?
Even if they were improperly adjusted, that would not give you a different "buzz" between left & right turns.

My Pilot Road-2 tires also make the subtle snow tire like noise -but- if it's different when comparing left & right turns THAT is is the ring gear moving towards then away from the pinion gear it meshes with. Gears mesh very tightly on left turns, not so tightly on right turns. Excess bearing clearance (from a failing bearing) allows those events to happen.

Go into the dealer and tell them about the buzz. Show them the 9-3 and 12-6 O-Clock excess wheel movements. Tell them about the new noise difference between left and right corners (ruling out the tires!!). Tell them there is a new and upsetting stability "disconnect" midway when you ride thru a left/right chicane. ALL those things are indicative of early FD bearing failure.

!!! Note that the warranty is 3 months from expiration and you want this impending failure logged in as occurring during the covered period. If you happen to get chatty with them, mention in passing that your trying to decide between a future Moto Guzzi Grizzo or a new R1200R.

.

[NoRRmad]

jm1515 is three months past warranty.

[CycleRob]

"I was thinking of riding into the dealer, and being only 3 months out of warranty . . . . "

Woops!
Speed reading=1
Comprehension=0

[boxermania]

jm1515

With the bike on the centerstand and in neutral, rotate the rear tire in the forward direction.....do you feel any roughness or does the tire turn freely (minus the disc brake drag of course)? Rough....is an indication that there is the begining of bearing race damage.

If anyone has replaced the FD bearing recently and still has it, I would like to get it to cut it up and analyze it. Will pay for the shipping too.....yes, I'm generous and like to look into this things. Remember, practice makes perfect.

[Byrdguy]

Analyze a bad bearing? To what end? They fail, they get replaced.

[HikerGlenn]

I have the same movement in my rear wheel. I've talked to several "guru's" on the various nets, and all seem think FD pivot bearings.(My rear wheel feels totally smooth upon rotation). My bike only has 7k miles, and I can't believe it would be the FD wheel bearings. I am going to replace the stock pivot bearings with some JL bushings to eliminate the problem for good. My 2 cents-Glenn.

[jm1515]

I have the same movement in my rear wheel. I've talked to several "guru's" on the various nets, and all seem think FD pivot bearings.(My rear wheel feels totally smooth upon rotation). My bike only has 7k miles, and I can't believe it would be the FD wheel bearings. I am going to replace the stock pivot bearings with some JL bushings to eliminate the problem for good. My 2 cents-Glenn.

I guess it depends on what guru you talk to, but I've read that if there is movement in both planes, it's most likely the big bearing...and, oh BTW, check the pivots while you're in there.
Anyway...my wheel turns smoothly in both directions hot or cold. I've got the JL paralever bushings on order....I guess I'll see if they solve any of this.
Thanx for all the input guys..... I just checked again (cold) and the 3-9 is so infinitesimal and the 12-6 so very small...I'm just going to ride it till my bushings are installed....

[boxermania]

Byrdguy

You are right, it breaks and it gets replaced. On the other hand there are people that frequent this forum, like yours truly, that enjoy researching why things fail, especially when the failure is premature.

Since we have established that you know very little about bearings, or plainly don't care, no offense intended, let it be known that there is a term in bearings denoted the L10 life which defines the expected life for a grouping of bearings in a particular application. Not to bore you, the L10 life is arrived at when 10% of the sample fails, at this time the run time of the samples is chosen as the "end of life" for the bearing.

That being said......the life of the failed bearings in the FD of our bikes is nowhere near the expected L10 life for the bearing. So then I feel the need to find what is causing the bearings to fail.....since BMW Motorad simply does little about it, in most instances.

For your further edification sources of failure can be, improper selection of bearing for the intended use, lateral forces (thrust), improper lubricant, improper fitment, too little lubricant, water, rolling elements sliding instead of rolling, excessive vibration, etc.

So in closing, I enjoy and have the ability to look at a bearing and pretty much establish the mode of failure, that doesn't mean much to you but it does to me and since this is an interactive forum I like to share my findings as well.

[HikerGlenn]

jm1515, I'm pretty sure my problem is the pivot bearings, as I can hold onto the swingarm, and grasping only the final drive casing, push to and fro, up and down (hard) and get a "click, clunk or pop" whatever you want to call it. It's the same exact noise as when grabbing the tire itself, so I know it's got to be those darn pivot bearings. I talked to Paul Glaves about this, and he agrees. He said he has three sets of the JL bushings in his bikes-no more problems. Like you, my "play" is so small, I will install those bushings this winter, when riding season slows down for me.-Glenn.

[Byrdguy]

I know enough about bearings to know that there are occasional failures (as is the case with any part in any mechanical device) so, you're right, I don't care about the odd bearing that doesn't live out its expected life. If there are repeated failures on the same vehicle, or many of the same model of vehicle, then there is either a design failure (wrong bearing for the application) or inferior manufacturing or materials of the bearing applied, I would be interested in knowing which to be the case. That being said, I don't believe there is a design failure since most FDs go many,many miles with no problems, so, were it me, I would repair the unit, reinstall, and not worry about it. I'm 61 years old and have been wrenching on all things mechanical since I was 15 so I's knows a little. Let us know when you find the cause of said failure, I'd bet that poor manufacturing tolerances or out of spec materials to be the culprit. Basically it was a "bad bearing". I don't know everything, but I know what I know.

[boxermania]

Byrdguy

There have been a significant FD bearing failures. Most of them have been on the early 2001 and 2002 R1150's and specially the RT's of the same vintage. I would say that by 2003 the failures have subsided. My initial take is the the bearing was mis-applied for the service as those that have replaced it don't seem to have had additional failures.

So back to my original request, if anyone has a failed bearing, let me have it so I can have some fun with it.

[Byrdguy]

So, do you suspect inferior material or wrong tolerances on the bad ones? I have a late 01/early02 and so far so good (only about 15k miles though) but it's good to know the replacements are more up to snuff. I know one guy with an 02 GS and he had a FD bearing failure, but had upwards of 50k miles on it, and I guess after thinking about it, that is really premature also. They should go upwards of 100K miles. IMHO.

[NoRRmad]

I have an early '02, and the FD failed at 32,000 miles.

[boxermania]

Let me put it in perspective. A FD failure from 30K to 50K is like getting 8K to 12K miles out of a current set of cage tires....

[jm1515]

It's been ~1200miles since I installed my Paralever bushings and ~400miles since I re-torqued them.
I have absolutely no movement in the rear wheel now ...solid as a rock...
I still get this very slight buzz when turning hard, tho. Only now it occurs only between 28 ~ 40mph, not at any other speed, or at slow turns anymore. It is also the same on rights and lefts....
I just did a 36k service and the FD oil and mag bolt were clean as a whistle, so I'm chalking this up to PR2 noise....for now
So my pivot bearings lasted 31k. I guess I could have re-torqued them, but I could see minor flat spots on the rollers and a few corresponding 'burned in' areas on the inner races when I took them out. I'm glad I went with the bushings....

[Dr. Strangelove]

what should the final drive oil look like when replaced?

Just got back from a 4700 mile dusty ride across Texas and into Colorado. I did the 36 k oil changes when I got home. The FD oil had some VERY VERY fine particulate matter in it. it did not feel gritty and looked to be the same stuff you see on the magnetic plug. It looked to be the size of dust particles, no shavings or anything shiny at all. The first time I replaced the FD oil at 24 k it was clear with a slight honey color iirc

I want to hear that is normal and that is what the oil should do, pick up dirt and keep it away from bearings.

I will replace it again when I get home from this trip and look at it if need be.

thanks

John