R1150 (RS) Gearbox / Clutch noise

[Kenny S]

Hi Folks,

 

I've had my R1150 RS for ten years now. After sitting over winter when I started the bike there is a terrible bearing type rumble coming from the gearbox area.
The noise goes away when you pull the clutch lever in, and returns when the clutch is released.
I'm thinking that this is likely the input shaft bearing but would appreciate if anyone has any other suggestions before I pull the box apart - I've already separated the gearbox/back end from the motor.

Thanks!

[dirtrider]

10 hours ago, Kenny S said:

Hi Folks,

 

I've had my R1150 RS for ten years now. After sitting over winter when I started the bike there is a terrible bearing type rumble coming from the gearbox area.
The noise goes away when you pull the clutch lever in, and returns when the clutch is released.
I'm thinking that this is likely the input shaft bearing but would appreciate if anyone has any other suggestions before I pull the box apart - I've already separated the gearbox/back end from the motor.

Thanks!

Afternoon Kenny

 

It seem strange that an input shaft bearing would be good when you parked it then went bad just sitting there.

 

It might be the slave cylinder/pushrod making noise if the pushrod rusted to the diaphragm spring over the storage period. 

 

Try lightly pulling on the clutch lever looking for a noise change,  just pull the clutch lever enough to load the slave cylinder bearing but not enough to disengage the clutch. 

[Kenny S]

Hi DR,

 

Thanks for the info. I think you may well be correct about the slave cylinder, I've not got it here but it didn't look very healthy inside when I removed it.
I'll be back down to take another look at it tonight. I've pulled the box off anyway as the bike is 20 years old now and done over 30k so I thought it was worth checking the splines etc.

 

Cheers,

 

Kenny

[Lowndes]

Replace the clutch slave cyl AND drill a weep hole for it while you have the tranny off.  It's CHEAP insurance.

[Kenny S]

3 minutes ago, Lowndes said:

Replace the clutch slave cyl AND drill a weep hole for it while you have the tranny off.  It's CHEAP insurance.

Currently looking to see if anyone makes an upgraded slave cylinder, the current one is shot, OEM and not that old.

[taylor1]

My OEM slave crapped the bed @ 7000 miles on my RT . Replaced it with the one from Beemer boneyard and @ 50,000 later, all is kosher.

[Kenny S]

I've been looking at Moto-Bins and James Sherlock over here - pretty sure it's the same one they sell 

[Lowndes]

The piston in the slave cyl has a small sealed bearing that is the throwout bearing.  The clutch rod is spinning with the crankshaft whenever the engine is running, clutch in or out.  The bearing does have more load with the clutch lever pulled in (clutch disengaged).  When that little bearing goes out the piston starts spinning and that can't last long.  Then the clutch fluid escapes and travels along the clutch rod straight to the clutch friction disc and you replace the clutch.  A weep hole would prevent the fluid from getting to the clutch.  Not sure why BMW didn't see fit to provide a weep hole.

 

[Kenny S]

10 minutes ago, Lowndes said:

The piston in the slave cyl has a small sealed bearing that is the throwout bearing.  The clutch rod is spinning with the crankshaft whenever the engine is running, clutch in or out.  The bearing does have more load with the clutch lever pulled in (clutch disengaged).  When that little bearing goes out the piston starts spinning and that can't last long.  Then the clutch fluid escapes and travels along the clutch rod straight to the clutch friction disc and you replace the clutch.  A weep hole would prevent the fluid from getting to the clutch.  Not sure why BMW didn't see fit to provide a weep hole.

Thanks, I wasn't very up to date with how the clutch operated, that little bearing isn't the best is it? The slave has already been replaced, this will be the second one. Wil take a look a at making a little weep hole.

[Kenny S]

So despite having all my fingers crossed and doing my best to convince myself that the gearbox is fine, it isn't. 

 

The slave cylinder was pretty filthy but once I'd cleaned it up it was obvious the the bearing was good, so then I drained the box and pulled out the magnet in the bottom to find it was covered in shrapnel.

Rotating the input shaft at a decent speed resulted in quite a loud noise from the box too.
So we opened the box to find the input shaft bearing at the input side had failed, and three of the other bearings feel like they are on their way out too, with a fair bit of play in them.

Todays job is to order up replacements for all six shaft bearings along with new seals, also need to find a suitable puller to get the bearings off.

There are a couple of things I find a bit strange though.

There are 4 TM205 bearings, two on the output shaft and two on the intermediate. In my box they are all NSK but two are Japanese origin (orange seals) and two are English (black seals). 

I thought this was a bit odd for a factory to have a mix like that. I bought the bike 10 years ago with 10k miles on the clock, one owner running about 1k miles per year, so I don't expect the box has been opened before - certainly nothing in the service docs to show this.
I am lucky that I have a close friend who is a MotoGP mechanic, currently working for SRT - he builds all the gearboxes for them so very handy to know, he's helping me rebuild it.
He is of the opinion that the box is a terrible design, running sealed bearings means its always going to fail. It does seem very odd that the bearing are not open and oil fed.

I've attached some photos for info.

 

Cheers,

 

Kenny

 

[9Mary7]

[Kenny S]

Finally got some time at the weekend to start getting the gearbox back together.

The shaft bearings are very close to the gears which meant finding a set of bearing separators to pull some of the them off, others are easy enough as you can pull the gear along with the bearing.
Bearing separator tool from BMW was £182, same kit from Kukko was £285 so I decided to try a cheap £25 set I found on Ebay.
These did the trick although they did bend a bit.

 

Using the bearing separators and a 32 tonne press I had access to got the bearings changed over fairly quickly. Using a digital Vernier's to check the dimensions were still the same. 

Then I cleaned up everything as much as I could, using an air line to blow off any dirt left behind and put the three shafts together. After removing all the seals form the casing I then heated it up as per the instructions using a hot air gun and a handy little laser temperature gauge I use for the tyres on my track car. The manual says 100-120 degrees C, once I'd got the temps up the three shafts dropped straight in.
I then built up the rest of the box following the BMW manual, it's now ready for the other half of the casing to go on.

I then set about drilling a weep hole as recommended by Lowndes on here. Got a 1mm pilot hole drilled OK but my 4mm was so blunt I wouldn't look at cutting the alloy of the casing so that's how I left it.
Domestic stuff took over yesterday so hopefully back down to it tonight.

Cheers 

[Kenny S]

Hi Folks,

 

Quick question - I've put the bike back together but unfortunately the gear position indicator got damaged in the process. My friend rebuilt it but it's obviously not right as it's not showing the correct gears.
I'm also not getting any neutral light, I believe this is also a function of the position indicator - is that correct?

Going to buy a new one anyway but I'm hoping this will solve the neutral light problem too as I cannot get the bike to turn the starter.

 

Thanks,

 

Kenny

[dirtrider]

1 hour ago, Kenny S said:

Hi Folks,

 

Quick question - I've put the bike back together but unfortunately the gear position indicator got damaged in the process. My friend rebuilt it but it's obviously not right as it's not showing the correct gears.
I'm also not getting any neutral light, I believe this is also a function of the position indicator - is that correct?

Going to buy a new one anyway but I'm hoping this will solve the neutral light problem too as I cannot get the bike to turn the starter.

 

Afternoon  Kenny

 

Yes, the gear indicator switch assembly  contains the neutral safety switch.

 

Have you tried holding the clutch lever in?  That should by-pass the trans switch & allow it to crank (unless the clutch switch is also bad). If the clutch lever switch is bad then you can just jumper the switch  wires together to by-pass the bad clutch lever switch.

[Jim Moore]

You can also pull the starter relay and jump hole two to hole 6 with a piece of wire (key on). "VROOOM!"

[Lowndes]

Beautiful pics, BTW!!

[Kenny S]

So the new gear indicator switch has solved the starting problem. As soon as I connected it I got a neutral light and everything working again 

I was a bit taken aback though as the bike hasn't been run in about a year, first press of the button it immediately burst in to life and went to 6k revs - not ideal!
 

Time was short as I had just nipped down to the bike (It's currently at my storage unit where I keep my cars about five miles away) during lunch so I'll be back there tonight to try and find out what's making it rev up and generally tidy up cables etc.

Very happy though that it's now starting   might make this trip to Islay this weekend after all.

 

Sláinte!

[dirtrider]

6 minutes ago, Kenny S said:

So the new gear indicator switch has solved the starting problem. As soon as I connected it I got a neutral light and everything working again 

I was a bit taken aback though as the bike hasn't been run in about a year, first press of the button it immediately burst in to life and went to 6k revs - not ideal!
 

Time was short as I had just nipped down to the bike (It's currently at my storage unit where I keep my cars about five miles away) during lunch so I'll be back there tonight to try and find out what's making it rev up and generally tidy up cables etc.

Very happy though that it's now starting   might make this trip to Islay this weekend after all.

 

Sláinte!

Morning Kenny S

 

On you very high idle situation_

 

Look for throttle cables not fully seated at the throttle body adjusters with both cables FULLY seated IN the adjusters,  look for throttle cables partially pulled out of the bowden box (cable splitter box), look for air leaks in the air boots between the throttle bodies & the cylinder heads, look for a tight choke cable, look for both side throttle body cams to fully return to their stop screws (with choke off). 

 

Probably something simple.  

[Kenny S]

Thanks dirtrider - you've saved me the trouble of coming up with a list of potentials 
I'll run through your list later, I'm sure it'll be one of those things. 

[Kenny S]

Just wanted to say thanks for the help and advice given on here - great to be able to share the knowledge, certainly helped me get the job completed 

Finally got the bike back on it's wheels last night after tidying up the hoses and cables and fitting a new battery. 
The high idle was caused by the throttle cables not being seated properly at the throttle bodies - a very quick fix.

Bike goes for it's MOT test today, so my few days away with my mates looks like it'll go ahead.
Next on the list is ABS delete.

Cheers 

 

 

That'll be the problem

 

Ready to roll - will be going for a gentle test ride tonight assuming it passes it's test.