Final Drive Problems.....I think

Looking for your input/suggestions on a final drive rebuild. Tom Cutter of Rubber Chicken Racing Garage (RCRG) appears to get high accolades, but are there other shops/individuals you can recommend.

1st off: It is a 04 R1150RT with 43,000 miles on the clock, and I ride year round including cold wet winters (Northeast region).

Symptoms: A noticeable "rumbling" sensation with bike underway, more noticeable with a lean to the left or to right (more so on the left). Rear wheel is solid if I grab it at the 6 and 12 position. but if I grab it at the 3 and 9 position, it has a shimmy/wiggle. With rear brake applied the wiggle/shimmy is still there, which general knowledge (various websites) indicates it is more than likely the FD, and not the pivot bearing. FD fluid is changed on a regular basis (+/- 10,000 miles), and although slightly dark, no shinny flakes or bits of metal on the magnet, which I assume means that I may have caught it before more expensive/dangerous problems transpired.

FYI - All prices noted below are estimates on my part, so pls feel free to make suggestions regarding gross mis-calculation.

From what I can ascertain, on a cost savings basis, is to remove the final drive myself and send it out for rebuild. Cost should be in the +/- $800.00 range, and since I will have to remove the final drive from the bike then I might as well replace the paralever pivot bearings, approximately $150.00 - $170.00 in parts.

My wrenching skills are about a 5 or 6 on a scale of 1 - 10....but that may be a stretch.

Options

#1) Purchase and replace with new final drive: +/- $1,400, if I do the work myself. +/- $2,000 if BMW does it for me

#2) Purchase and replace with used final drive: +/- $400.00, if I do the work myself. Unknown if BMW does it for me (assuming that they would install a "used" FD for liability reasons), and who knows the condition of the used FD anyway...could be right back here in another few thousand miles.

#3) As described above, sending my drive to RCRG for rebuild, but undetermined amount of down time as he is on vacation until May 1st.

Safety first, but cost consideration a strong second. I just wnet through a messy divorce, and between attorney's, settelment cost and recent refi on the house, funds are very tight, So, please give me your thoughts and/or suggestions......including consideration of an FJR, ST, Connie....etc. (lol)

Jeff

I can't help with your first question ( who to fix it ) but I would suggest that you check the pivot bearings & rule them out first. Check the torque on the left side pivot bearing before you take the rear end out and see if there is any play. Your going to have to take the rear end out of the bike anyways. If its not the bearings than your left with the rear end itself.

The bearings themselves are not that expensive and the costs would only go up if you had to replace the pivot pins. It would seem that you have enough mechancial abilitiy with this fourm & some kind of manual to tackle this project.

After your all done I would suggest that you put the pivot bearings and rear spline on your maintenance chart say every 30 K miles or so.

Good luck

You use your finger as movement detection instrument.

With drive cool, on center stand, rear wheel off ground, put finger in gap between rear brake caliper and disk, with other hand wiggle at 12 and 6. If you do not feel movement then drive is good.

Take the rubber boot loose, find place to put finger tip between swingarm housing and final drive near the bearing, check for movement at 3 and 9.

A finger can detect movement of .001 this way.

If you are tight at 6 and 12, your final drive is good, it is the pivot bearings, not a hard job at all.

If you need to replace the big bearing, it is not hard at all either, you do not have to take the final drive off, you can do it mounted on the bike..

Hint, if you get allen sockets from Harbor freight they have the 7MM you need and also one that fits the pivot pins in one inexpensive set.

Rod

It seems to me that the caliper is tight to the FD case, and the disk is tight to the crowngear/wheel assembly. Firm application of the rear brake would "lock" the crowngear/wheel assembly tight relative to the FD case and if you still feel the play with the brake tightly applied it is not the crowngear moving relative to the case. So I think paralever bearings.

BUT, that does not explain the rumble and/or vibration.

I would check things pretty thoroughly to identify the source of the rumble, in addition to checking and probably replacing the paralever bearings. I would plan on removing the swingarm and manually and visually checking the driveshaft universal joints. The rear joint is out with the final drive but really checking the front joint requires having the front half of the shaft in you hand. If it is really bad you can detect the slop with it in place by reaching into the swingarm but it can be bad but not quite ready to fall apart and you can't detect it because of the rotary play in the transmission gearsets.

Now, the rumble may well be a tire - very common with ME880s and several other brand/model tires in my experience. Calm going straight but a rumble from the tread as soon as you lean a bit. But the final drive needs to come off so the swingarm and driveshaft are a short few steps away. I would pull and inspect the driveshaft before I concluded it was the tires. And don't forget to properly phase the two U joints when you put it back together.

They need to look like this!

On my 2000rt I also started to experience the "rumbling" sensation making turns left and right, I did not notice it going straight. Checking the rear wheel as instructed from this forum I had movement which indicated the pivot bearings. While I had the final drive and transmission out to lube the input shaft I replaced the bearings with bushings from rubber chicken. That fixed my problem and now is smooth as silk. I did all this work as a newbie with help from this site and was able to complete the task. It sounds like you will be able to do the same thing. Good luck.

The rumbling you describe sounds like standard tire wear. It's noisier in a left turn (or lean), but that's a tire thread. Check those pivots.

concurring with others on importance of not discounting the pivot bearings. those are a much more likely to wear out part than anything in the FD. If they have not been previously replaced, count yourself as very lucky for them to have lasted this long, get the bushings from Tom, and do that repair, with or without any FD action.

Ditto, ditto, ditto with everyone else, especially Paul Glaves.

Driveshaft phasing makes a big difference vibration wise, which I learned first hand by doing, and re-doing, my own work, heh, heh. That and the swingarm pivot bearings. Replace then with the bushing set from Rubber Chicken.

My 94 R11RS has 145,000 on the clock, on the original untouched rear final drive. Original rear FD bearings. I replaced the swingarm bearings about 20,000 miles past. I also installed a low miles used driveshaft assembly for a R1150 when the original driveshaft was rumbling/vibrating, but that was at 115,000 miles. I have ridden nearly all those miles in Wisconsin, early March to early December, so there is a lot of wet riding in between that.

Final Drive fluid "may" indicate if there is any concern about the FD. It must never be creamy and frothy (water in the fluid), but dark is ok. Stinky (other than normal for Hypoid Gear lube) is not normal either. I only use 75W90 GL5 Synthetic fluid in my final drive. Never run 75W140, not a good choice and not necessary.

I just put a new Metzler Tourance on my GSA and have noticed a bit of rumble when I turn left or right. I did not have that noise until I changed the rear tire. I had Bridgestones on it before. Bike now has 14,600 mile on it. I assume it is the tires.

OK...let's get ready to rrrummble......

In Sept '08 I noticed the same rumble/vibe as the OP while making a hard left onto the street where I live. This was ~1000mi after switching tires from the OE Pilot Roads to the new PR2s.
I got this vibe whenever leaned over...all is quiet while going straight. Checked for wheel play and sure enuf had some movement @3 & 9.
After some investigation I installed the JL bushings. That was ~11k miles ago and ever since I have had no problems w/ wheel slop. None....but I still get the vibe whenever leaned over.
Funny, but it only happens between 25mph and ~40mph....
In July of LY I was changing tires, installing another PR2 on the rear, when I noticed I had gear oil in the wheel hub.
After consultation with the great Rubber Chicken himself, I sent my FD to Tom and he did a big bearing/shim replacement, + sealed the hub as he described it. I also had MachineService re-build my FD U-Joint at the same time.
That was about 4k miles ago, and seems to have fixed my oil-in-the-hub problem. Also, 2 samples of FD oil to Blackstone have shown nothing unusual...
Sooo...my rear tire is solid as a rock, no lube anymore in the hub, but I still feel the vibes when leaned over, albeit in a somewhat narrow speed range.
Tire noise, right?????

I think it's your tires. Put your bike on the centerstand and get the rear wheel off the ground. Put the bike in neutral and spin the rear wheel by hand. If your big bearing is going bad, you will feel a very distinct (and sickening) grinding feeling as the wheel turns.

A tiny amount of 3-9 play in your rear end is not good. But it's not "OMG I gotta spend $1000 right now" bad. It's "hmmm, I better keep an eye on that and maybe look into getting a set of bushings" bad. If you simply MUST spend some money right now, buy a set of bushings from Tom Cutter.

JimMoore said:

I think it's your tires. Put your bike on the centerstand and get the rear wheel off the ground. Put the bike in neutral and spin the rear wheel by hand. If your big bearing is going bad, you will feel a very distinct (and sickening) grinding feeling as the wheel turns.

A tiny amount of 3-9 play in your rear end is not good. But it's not "OMG I gotta spend $1000 right now" bad. It's "hmmm, I better keep an eye on that and maybe look into getting a set of bushings" bad. If you simply MUST spend some money right now, buy a set of bushings from Tom Cutter.

Click to expand...

I vote tires too. My current well worn ME880's rumble when leaned. FWIW, I did have my F/D crown bearing fail at 48k. That rumble was clearly felt through the pegs, and obvious when turning the rear wheel by hand. Removing the wheel and turning the hub by hand removed all doubt. Never leaked, never had play, but upon inspection, the crown bearing was toast with the cage completely destroyed. Maybe pull the wheel and see how it feels turning it by hand?

Another vote for tires. I had well worn 880's on my last bike and thought I was getting a flat when turning due to the loud noise.

So... after reading all this I went out and checked my rear wheel for play at the 3-9 position, the 12-6 position, the 1-7 position and the 11-5 position. What I discovered is that it has about a 1 mm. play all around the rear wheel. Good? Bad? Am I gonna have to pull out the plastic?

Thanks to one and all

I want to thank everyone for their thoughts, and suggestions regarding the "rumble" feeling was was getting in the rear wheel of my 04 R1150RT. I just replaced my rear rire (Mich PR2 with about 2000 miles on it), with a new Metezler Interact Z6. Took her out for a little neighborhood ride, and it appears to be okay. Still a little movement at 3 and 6 so JL bronze bushings from Rubber Chicken may still be a possibility. But, the rumble is gone! I am going to take her to work tomorrow, about 70 miles R/T, and hope to get a good opportuity to really see if it as the tire. I will post again tomorrow when I get home!

Thanks again!

FYI, I recently had the crown bearing, seals and FD pivot pin bearings replaced at Ride West BMW dealership in Seattle for $400. I delivered my FD to them. And I had both u-joints replaced by Machine Services for $300 tax and shipping. Ofcourse I did all the disassembly and assembly myself.