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FD Time

lgb

New member
Well, from the looks of things and the sound of things... it's Final Drive Time! :brad
Mileage reached 46K. I'm not real impressed but maybe I should be thankful it didn't happen sooner, or on a long trip, or it didn't grenade and leave me on the side of the road in the middle of the desert.
 

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Hang on a minute...
If those two tiny flakes on your finger are all you found in 46K miles I would not be jumping to conclusions just yet. Does the bearing feel rough? Sometimes it's easier to feel for this with the wheel off.
 
If you are expecting the FD fluid to be exactly clean and totally free of any silver/grey color, then I suggest you first talk to some experienced mechanics before tearing into it.

If it does not exhibit any free play or roughness, then its probably fine.
 
A little "mud" or some hairs are OK. Distinct flakes or chips come from a bearing race and it will be downhill from there, fairly quickly.
 
There are plenty of threads here with pictorials demonstrating the procedure, go for it if indications direct you to that direction.
 
If you are expecting the FD fluid to be exactly clean and totally free of any silver/grey color, then I suggest you first talk to some experienced mechanics before tearing into it.

If it does not exhibit any free play or roughness, then its probably fine.


It is a known reality that some final drives have a shorter life than others. Because of this I thought it might be better to change the fluid at 6K intervals. Cheap peace of mind you might say; others might say it's a waste of oil.

Anyway, at 42.5k I changed it prior to a 3K trip and I noticed a 'slight' silver particulate. I didn't think much of it other than a little dirty. Also noticed a slight amount of play in the rear wheel at the 12/6 position. During the 3K ride (two up) both of us noticed a droning coming from the rear as we leaned either left or right from center. It wasn't tires, at least I don't think it's the tires. I didn't like hearing the noise because it was indicative of impending bearing failure. Nothing happened on the trip.

Upon return I looked at the rear wheel play(more play), as well as a reputable dealer and an independent. Everyone said bearing replacement time. Although there isn't tangible flake or slivers of metal in the oil there seems to be enough to indicate replace it before the FD starts spewing all over the rear wheel. I feel the combination of checking the oil via this minder device and noting the sound and play helped determine it was time to rebuild the FD. We'll see...
 
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It's your money, your call. Are you sure it's not just loose or worn bearings at the pivot pins? The droning sound when leaned left or right sure sounds like worn tires to me. The smudge on your finger looks like normal wear to me. I have the FD Minder on my RT and check it at just about each gas-up and that's what I get on it. From far away, over the web, it looks like you're jumping the gun.

At 90k miles, my FD big bearing started to flake apart. This is just a little bit of what I had on the FD Minder 300 miles after I changed the FD Oil. I changed out the big bearing right after that.
 

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On the older Oilheads, the droning can certainly be caused by failed swingarm bearings. I had replaced mine with bushings (the bearing races had come apart) but last year I noticed the rythmic droning when leaned left or right. Checked the preload on the bushings and realized I needed to reset it. Droning now gone.

On my 94 RS I have 169k on the original final drive and at most I get some silver/grey paste on the drain plug when I change the fluid (last done at 166K), but no flakes/chips etc.
 
It's your money, your call. Are you sure it's not just loose or worn bearings at the pivot pins? The droning sound when leaned left or right sure sounds like worn tires to me. The smudge on your finger looks like normal wear to me. I have the FD Minder on my RT and check it at just about each gas-up and that's what I get on it. From far away, over the web, it looks like you're jumping the gun.

At 90k miles, my FD big bearing started to flake apart. This is just a little bit of what I had on the FD Minder 300 miles after I changed the FD Oil. I changed out the big bearing right after that.


I haven't torn the FD apart and really haven't decided to do it, or not, at this point. I felt all along that a little residual in the oil is normal.
The amount of particles that I see in your photo is more in line with.. time to rebuild/ replace. I'll check out the noise thing further and get another opinion or two.
I might just keep an eye on it and l do a rebuild when it's really saying, rebuild me.
 
+1 what the other guys have said. I'm at 89K, original FD, and see a bit of that smudge every time and that's with changing my fluid every 6k or so as well.
 
The bearing is right behind the seal. The seal costs about $30 and is simple to R&R. It might be worthwhile to pull the seal off and see what the bearing looks like. The bad ones I've seen are plainly obvious.
 
If you've just got a weeping seal, it's simple to R&R. Unless the bearing is actually broken into pieces I don't believe you can actually determine condition by pulling the seal. The drain plug will be much more indicative than what is visible behind the seal.
 
A little "mud" or some hairs are OK. Distinct flakes or chips come from a bearing race and it will be downhill from there, fairly quickly.

What about lash. My drive seems to have a lot of lash. Is that a problem? Previous owner took it into Deming Cycle years ago and had them adjust it. At 50K still runs great.
 
+1 what the other guys have said. I'm at 89K, original FD, and see a bit of that smudge every time and that's with changing my fluid every 6k or so as well.


Greetings Ron,

Well, I'm wondering what, if any, wheel play do you have at the 12/6 position? Is it tight? Does it have 3/32" play? Does it have 1/16" play? Or...any ?? Please describe. Mine has some. And some "service advisor experts" suggest that it's boarder line, some say too much and I should rebuild.

I realize there should be some residual in the oil, it's just about how much, coupled with other markers.

I'm going to say that my PR2 tires with some 7800 miles on them are the reason I hear the droning noise when leaning. I won't change them until I need to.

But, there's still wheel play. I'm inclined to do a watch and see. I know it doesn't seem normal, but I'll watch to see if oil is seep'n and to feel if there is more wheel play and to see if there is more residual on the minder.

Time will tell and I'll be reporting back in on the demise of my final drive...
Any suggestion's, and other observations mentioned, are appreciated.

Thanks to all!
 
Greetings Ron,

Well, I'm wondering what, if any, wheel play do you have at the 12/6 position? Is it tight? Does it have 3/32" play? Does it have 1/16" play? Or...any ?? Please describe. Mine has some. And some "service advisor experts" suggest that it's boarder line, some say too much and I should rebuild.

I realize there should be some residual in the oil, it's just about how much, coupled with other markers.

I'm going to say that my PR2 tires with some 7800 miles on them are the reason I hear the droning noise when leaning. I won't change them until I need to.

But, there's still wheel play. I'm inclined to do a watch and see. I know it doesn't seem normal, but I'll watch to see if oil is seep'n and to feel if there is more wheel play and to see if there is more residual on the minder.

Time will tell and I'll be reporting back in on the demise of my final drive...
Any suggestion's, and other observations mentioned, are appreciated.

Thanks to all!


If you've just got a weeping seal, it's simple to R&R. Unless the bearing is actually broken into pieces I don't believe you can actually determine condition by pulling the seal. The drain plug will be much more indicative than what is visible behind the seal.

Thanks for the insight Michael. But, I don't have a weeping seal. Some play, some noise (probably tyres) and some goop in the oil. We'll see what happens.
 
Remove the brake calliper (so you don't hear the pads on the disc) and spin the wheel, if there is a grumble its a sign of impending failure. If there is just a whirring sound then I would ride for a while longer and watch the magnet. Typically there are more/larger flakes than you have.
Any black fluff is perfectly normal.
BTW: I am assuming you have an Oilhead right?
It helps to fill out your profile.
 
Remove the brake calliper (so you don't hear the pads on the disc) and spin the wheel, if there is a grumble its a sign of impending failure. If there is just a whirring sound then I would ride for a while longer and watch the magnet. Typically there are more/larger flakes than you have.
Any black fluff is perfectly normal.
BTW: I am assuming you have an Oilhead right?
It helps to fill out your profile.

I need to do that profile thing... it helps. :thumb

The bike is a 2003 R1150RT with 46200 K on the odometer. HES was replaced at about 36500. Other than some oil it's been fine. And now, I'm not concerned about oil... it's used next to NONE in the last 3500 miles. I guess the rings finally said, "I'm seat'n in now"... and that is good news because I was about to turn the glove box into a oil reservoir with a drip system. :)
 
Seems like we're discussing three items here. The smudge that showed on the FD Minder; the droning noise when leaned over; and the play at the rear wheel.

My opinion, having never seen or taken a ride on your bike:
The smudge looks pretty normal, keep watching, keep up oil changes.
The droning is probably tires; 7,800 miles? Put on a new pair.
The play? Get the pivot bearings checked and tightened or replaced.
 
Seems like we're discussing three items here. The smudge that showed on the FD Minder; the droning noise when leaned over; and the play at the rear wheel.

My opinion, having never seen or taken a ride on your bike:
The smudge looks pretty normal, keep watching, keep up oil changes.
The droning is probably tires; 7,800 miles? Put on a new pair.
The play? Get the pivot bearings checked and tightened or replaced.


Thanks for the suggestions.

The play? Get the pivot bearings checked and tightened or replaced

Well, did the pivot bearings. The old ones didn't have a smoothness to them and they were looking alittle on the rusty side so they were repalced. The amount of wheel play remains is the same, about 3/32"
I'll continue to watch.
 
FD was replaced

Seems like we're discussing three items here. The smudge that showed on the FD Minder; the droning noise when leaned over; and the play at the rear wheel.

My opinion, having never seen or taken a ride on your bike:
The smudge looks pretty normal, keep watching, keep up oil changes.
The droning is probably tires; 7,800 miles? Put on a new pair.
The play? Get the pivot bearings checked and tightened or replaced.


At 48,200 miles and a trip of coming up, I decided to go for a rebuild on the original FD. With so much slop in the 6/12 position (about 6-7mm) I felt it was time to open up the can of worms... didn't want to push it any further. I've been monitoring the FD Minder and wheel movement for the last 6K miles. It was time...

There was no leaking of oil, nor excessive 'flakes' on the final drive minder or, in the drained oil. There was a distinct amount of silver particles suspended in the oil as noted in the first post. Upon opening and inspecting; the ring gear bearing showed signs of wear but not like it was ready to separate or fail. Of course it showed show signs of wear it had some mileage on it. On the other side... tapered bearing end... the axle was worn to the point that a new tapered bearing would just fall onto the shaft without any pressure. Thus the culprit, a worn axle shaft that caused the particulate and the slop.

I ended up replacing the 32/11 FD with the same. A used one with 6800 miles on it. It's seemingly in great shape. I was considering going to a 33/11 but the used one came up, so I got it.

Now I have the original that I was told could be rebuilt using a bearing glue, like Loctite Green. I'll wait and see. I might want to have a spare around...

So, there's no more wheel slop and no particulate in the oil (yet). Also, I noticed there wasn't any droning when leaning.
It's OK now...

Thanks to all that put in there .02 worth, it was appreciated! :thumb
 
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