Final Drive Play

[Jaracer64]

I was doing an oil change, and general look over on my bike Sunday night and came across a bit of a possible problem with my final drive.

 

00' R1100RT

89,000 Miles

 

If I grab the rear wheel I am getting about 1mm+- of play if rocked from either 12-6 or 9-3 positions.

 

This is the same with or without the rear brake applied.

 

My question is there another way to isolate if it is the pivot bearing or bearing on the crown gear? Or am I just having to admit the spendy path.

 

Is there a reliable place to look for parts\prices? So far I have not had too much luck online, nor had the time to run up to Gateway BMW.

 

Do you think this is too much play to keep the bike in service till the end of the season?

 

The plan was to take the FD apart once the weather starts to get cool.

 

Thanks in advance.

JS

[PAS]

This is how I found my problem. Loose pivot pin bearings

[dirtrider]

Evening Jaracer64

 

 

If your rear brake caliper is free floating like it should then applying the rear brake won't really change the wheel movement.

 

Only real way to tell IF the movement is in the crown bearing or the swing arm bearings is to check the movement between the rear brake rotor & something solid on the rear housing (like brake caliper bracket)

 

Stick your finger between the brake rotor & brake caliper mounting bracket then have someone move the rear wheel within it's free play.

 

You might very well find movement at BOTH the crown bearing & the swing arm bearings.

 

 

[Lemans]

I'll be following this thread with interest as I have a similar amount of play (k1300GT) immediately AFTER having the crown bearing replaced. It was considerably worse before. Still not clear on how to distinguish crown bearing play from swing arm bearing play after reading DR's instructions. At least it doesn't seem any worse after 8K miles.

[dirtrider]

I'll be following this thread with interest as I have a similar amount of play (k1300GT) immediately AFTER having the crown bearing replaced. It was considerably worse before. Still not clear on how to distinguish crown bearing play from swing arm bearing play after reading DR's instructions. At least it doesn't seem any worse after 8K miles.

 

Evening Lemans

 

Your K1300 has a later design final drive, unlike the 1100/1150 bike your K1300 drive is designed to operate with a little crown bearing play on a cold final drive.

 

On your K1300 about the only way to tell what you have is to use a dial indicator mounted to the drive itself (usually the brake caliper bracket) then measure to the wheel rim while moving wheel within it's free play.

 

On your K1300 too little cold-drive bearing movement is actually worse than a hair too much.

[Lemans]

Thanks, DR. Just reviewed the procedure on the shop manual DVD. Looks like I need to add a dial indicator to my toolbox. 0.5mm is within spec...bet I've got more than that.

[Jaracer64]

I will keep the thread updated with what we find. I am going to take the bike apart over the next few weeks, and order the needed parts.

 

Thanks Again guys!

[Jaracer64]

Well, I did not have much time to work on it yesterday. But I did get the wheel off, and poked around for play.

 

All I can say is ohh my word, how did I not notice before? There is play in everything..

 

Play list

Crown Bearing = Yep

Pivot Bearing = You bet

Forward Swing Arm = More play than the Cardinals

 

So.. I am going to tear it all down next week and order up some parts.

 

Anyone suggestions on sourcing parts?? Or just go to the dealer?

 

Thanks again guys!

[dirtrider]

Morning Jaracer64

 

 

I can't help you with parts as I usually just source from a dealer.

 

Not sure anymore but with my parts discount the crown bearing has always been cheaper from BMW dealer than from a bearing house & that also assures that you get the correct C-rated deep groove bearing.

 

You need to research that crown bearing install as there IS way more to replacing that crown bearing than just removing the side cover & plopping a new bearing in (the bearing preload needs to be checked & adjusted)

 

Do a little research first then come back here & ask any questions you have on doing that job at home.

[Jaracer64]

Dirtrider,

 

Thank you for the response,

 

I had planned on resetting the preload on the bearing while it was apart. When building truck axles I like to go towards the loose side of the spec and planned to do the same on the bike.

 

Thanks Again!

[dirtrider]

Afternoon Jaracer64

 

Unlike your truck axles with two tapered thrust bearings the BMW final drive only has one tapered bearing with the other side (crown bearing) being just a deep groove ball bearing.

 

If you go too loose with preload on a new bearing you might find the preload has turned into bearing play before bearing half life.

 

Too tight is worse than too loose but you don't want to be back where you at are now in 15,000 miles either.

[Jaracer64]

Very good point.

[Jaracer64]

Just an update guys, Sorry I failed at updating throughout the process....

 

At this point it is all back together and back on the road.

 

**List of replaced parts**

Swing arm bearings (Flat spots on rollers and loose)

Pivot Bearings (Loose and damaged cages)

Pinion Seal (Leaking)

Final Drive Crown Bearing (Cage intact but large amounts of lateral play)

Final Drive Crown Seal (Might as well)

Rear Brake Disk (Will have to update later with Chinese replacement review)

Brake Pads (EBC)

 

Overall the job was not too bad, Nothing was particularly difficult. The most challenging part was getting the proper torque on the pinion retainer and nut without a vise. (2 people to hold it down works)

 

How the bike rides now?

 

Bike feels more responsive, and the rear brake seems especially touchy.. Locks up and ABS kicks in quite easily compared to before.

 

So far the disk has been a worth while $60 experiment to replace my thin/grooved OE disk. I guess time will tell.

 

Rear disk used (http://www.ebay.com/itm/181196309446?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

 

Swing arm bearings used (http://www.ebay.com/itm/361157343177?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT)

 

Rest of the parts were sourced from Gateway BMW.

 

Sorry for the TLDR worthy post.

 

Thanks Again Guys! Ride Safe!

[Selden]

Jaracer64: I replaced the shagged rear rotor on my 1999 RT last fall with a ~$80 (including shipping) Chinese rotor. It is working just dandy, no signs of warping, no grooves, no grabbiness, etc. When I opened the box, I thought the quality of the machining was just as good as for any other new rotor I have seen.