K1200RS Speedo/Diff issue - K-Bikes.com - Excellence in Motion
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 12 (permalink) Old Apr 22nd, 2013, 12:31 am Thread Starter
Rookie
 
Join Date: Mar 2008
Location: Sydney, NSW, Australia
Posts: 37
Unhappy K1200RS Speedo/Diff issue

Learned gentlemen (and ladies, if we have any)

I've done a couple of searches on here, but apparently I've come up with something nobody has posted about before.

Returning from a rally ride last weekend, my K1200RS speedo decided that I wasn't going very fast at all. 98 K1200RS, one of the original "bumblebee" coloured ones.

In fact, the whole 300-odd kilometres of the ride home, I apparently didn't go faster than about 50k's an hour - although I speeds changed frequently, according to the needle.

My speedo indication is jumping up and down rapidly and very jerkily between a very small range between 0 and maybe 40-50k's an hour.

I believe (and a mechanic friend pretty much confirms) that this indicates the sender trigger ring inside the diff has broken loose - the receiver which sits in the diff housing seems to be working, it's just that the ring inside is not "locked" to the diff any more, so it spins at a different rate to the diff crown wheel and doesn't set the sensor off as regularly as it should.

I've done some searching on Max's fiche, and found what I *think* is the right part, but the diagram is very unclear, and I was hoping someone here could confirm I'm looking at the right bit.

The part I'm looking at it labelled "Impulse Sending Wheel" in the section titled 33_0640 - DIFFERENTIAL GEAR SET ", part number "33 12 1 451 181"

Anyone come across this one before? Am I looking at the right part?

Also, is it dangerous/risking further damage if I keep riding like this? Apart from the obvious risk of going too fast (not that I'd ever do that intentionally! ), would this be likely to do more damage to the diff if I kept riding?

And, one last one for shits and giggles, if someone out there has done it - how big a PITA would it be to pull the diff off and replace this ring to get the speedo working again?

Thanks for any input.
DaZZa is offline  
Sponsored Links
Advertisement
 
post #2 of 12 (permalink) Old Apr 22nd, 2013, 1:26 pm
Enthusiast
 
Join Date: Sep 2011
Location: Newport, Wales, United Kingdom
Posts: 273
Hiya Mate,

yep, that's the part, heres a couple of pics of my old R1100S Final drive, the Final drive is probably different but that Impulse wheel is the same part number.





To confirm whether it is the impulse that's moving, you should be able to remove the sensor then look down the hole and maybe push a pencil or similar in and turn the wheel by hand gently, should become apparent if that's the problem. On the R1100S Boxers, its quite a common issue for the cable from the sensor to the wiring loom to corrode at the multi plug which can also give similar symptoms.

Be aware that if you do need to replace the impulse wheel the tapered bearing obviously has to come off and there is a shim behind it, it is imperative that bearing goes back on EXACTLY as it came off, if you damage the bearing and have to put a new one on its a very specialised job setting the preload up.

Tim
------------------

2011 K1300GT
Special-K is offline  
post #3 of 12 (permalink) Old Apr 22nd, 2013, 5:06 pm Thread Starter
Rookie
 
Join Date: Mar 2008
Location: Sydney, NSW, Australia
Posts: 37
Quote:
Originally Posted by Special-K
Hiya Mate,
G'day.

Quote:
Originally Posted by Special-K
yep, that's the part, heres a couple of pics of my old R1100S Final drive, the Final drive is probably different but that Impulse wheel is the same part number.

(pics snipped to save quote space)

To confirm whether it is the impulse that's moving, you should be able to remove the sensor then look down the hole and maybe push a pencil or similar in and turn the wheel by hand gently, should become apparent if that's the problem. On the R1100S Boxers, its quite a common issue for the cable from the sensor to the wiring loom to corrode at the multi plug which can also give similar symptoms.
Thanks for that - this is basically what we did - luckily, one of the guys on the ride is a mechanic, and he did exactly that - pulled the sensor and stuck his finger (which is way smaller than mine, and could actually fit!) and that was what he felt.

I don't think it's the sensor, but we'll pull it and check the plug anyway just to be sure before we rush out and pull the diff off.

Quote:
Originally Posted by Special-K
Be aware that if you do need to replace the impulse wheel the tapered bearing obviously has to come off and there is a shim behind it, it is imperative that bearing goes back on EXACTLY as it came off, if you damage the bearing and have to put a new one on its a very specialised job setting the preload up.
Now that bit scares me - I'm not really setup to do bearings - when you say "exactly as it came off", you're talking roller alignment etc, yeah?

Also, how in hell does the sender wheel actually stay ON? I can't see a bolt of any form of fastening - is it just a press/squeeze fit, or is there some kind of loctite I may be lucky enough to just replace to restore it?

The part isn't expensive, as far as I can tell, I'm just really wary of the bearing bit!

Cheers and thanks!
DaZZa is offline  
Sponsored Links
Advertisement
 
post #4 of 12 (permalink) Old Apr 23rd, 2013, 11:24 am
Addict
 
Join Date: Mar 2004
Location: , , UK
Posts: 3,750
Ok before you start pulling the final drive apart you must check something else first.

Under/around the right hand seat rail you will find a bunch of wiring and connectors. One of those connects the speedo senso to the speedo head. Water tends to run off the seat, down the sides and on to those connectors and the pins can start going green and corroded.

Carefully separate each connector, clean the pins and sockets with a switch cleaner.

Once you have done that, if the problem is still there then you may be into fixing the sensor ring in the drive. Fortunately, it does not involve removing the pinion, but you should still be prepared to check your bearing pre-load, even putting back the same shims. Personally I would hang an oscilloscope on the sensor terminal on the speedo head with the rear wheel running off the ground for a second check. I think it is 6 impules per wheel shaft revolution.

Several have had that sensor ring work loose and you can see it/poke it through the sensor hole (use a bright led light). It seems as if it is just a friction fit on the shaft journal. From memory, I think most throughly clean/degrease the shaft and ring and fit it back with loctite bearing lock. There is no mechanical fixing, it is just a friction push fit.



Never pay again for live sex! | Hot girls doing naughty stuff for free! | Chat for free!
voxmagna is offline  
post #5 of 12 (permalink) Old Apr 23rd, 2013, 3:52 pm
Enthusiast
 
Join Date: Sep 2011
Location: Newport, Wales, United Kingdom
Posts: 273
Quote:
Originally Posted by DaZZa
G'day.





Now that bit scares me - I'm not really setup to do bearings - when you say "exactly as it came off", you're talking roller alignment etc, yeah?

Also, how in hell does the sender wheel actually stay ON? I can't see a bolt of any form of fastening - is it just a press/squeeze fit, or is there some kind of loctite I may be lucky enough to just replace to restore it?

The part isn't expensive, as far as I can tell, I'm just really wary of the bearing bit!

Cheers and thanks!

As long as the same bearing and shim goes back on properly seated you should be ok, I mentioned preload, that's rubbish, it controls ring gear backlash.

With the speedo ring I think you just gently heat it up and it expands enough to slip on.

Oh yeah, and what Voxmagna said above is what I was saying about the plug on the R1100S, same thing and definitely more common than the speedo ring slipping.

Tim
------------------

2011 K1300GT
Special-K is offline  
post #6 of 12 (permalink) Old Apr 23rd, 2013, 5:02 pm Thread Starter
Rookie
 
Join Date: Mar 2008
Location: Sydney, NSW, Australia
Posts: 37
hi Voxmagna, thanks for your input.

Quote:
Originally Posted by voxmagna
Ok before you start pulling the final drive apart you must check something else first.

Under/around the right hand seat rail you will find a bunch of wiring and connectors. One of those connects the speedo senso to the speedo head. Water tends to run off the seat, down the sides and on to those connectors and the pins can start going green and corroded.

Carefully separate each connector, clean the pins and sockets with a switch cleaner.
Hmmm, OK, the ride day before this occurred *was* the rain ride from hell (my wets held out for maybe 50k's out of 300-odd - by the end of it, I wrung at least a litre of water from my gloves, and poured a good half litre from my boots!) - is it common for this to come on so fast after a really wet day?

I don't often ride when wet (I wear specs, and my helmet is absolutely hopeless with the visor closed, so I end up with a wet face because I have to leave it open a touch to avoid fogging), so it's really the first time in a long while the bike has gotten this wet.

Quote:
Originally Posted by voxmagna
Once you have done that, if the problem is still there then you may be into fixing the sensor ring in the drive. Fortunately, it does not involve removing the pinion, but you should still be prepared to check your bearing pre-load, even putting back the same shims. Personally I would hang an oscilloscope on the sensor terminal on the speedo head with the rear wheel running off the ground for a second check. I think it is 6 impules per wheel shaft revolution.
Well, I'll definitely be giving the sensor connector a look before I go pulling the diff - I really, really don't want to do that if I can avoid it.

Quote:
Originally Posted by voxmagna
Several have had that sensor ring work loose and you can see it/poke it through the sensor hole (use a bright led light). It seems as if it is just a friction fit on the shaft journal. From memory, I think most throughly clean/degrease the shaft and ring and fit it back with loctite bearing lock. There is no mechanical fixing, it is just a friction push fit.
OK - if it does turn out to be the ring rather than the sensor, if it's not physically busted, is it safe to re-use the existing one with the application of loctite? Or would fatigue have caused it to come loose rather than just mechanical stress/breaking of the existing loctite?

Really appreciate your comments - forums like this are a haven for the less-mechanically experienced/adept like me - I don't input much (except stupid questions) because I don't know a lot that guys like you don't know better, but it's always good to be able to ask something and know that someone out there will most likely know the answer!

Cheers
DaZZa is offline  
post #7 of 12 (permalink) Old Apr 23rd, 2013, 5:04 pm Thread Starter
Rookie
 
Join Date: Mar 2008
Location: Sydney, NSW, Australia
Posts: 37
Quote:
Originally Posted by Special-K
As long as the same bearing and shim goes back on properly seated you should be ok, I mentioned preload, that's rubbish, it controls ring gear backlash.

With the speedo ring I think you just gently heat it up and it expands enough to slip on.

Oh yeah, and what Voxmagna said above is what I was saying about the plug on the R1100S, same thing and definitely more common than the speedo ring slipping.
Well, I'll definitely be taking advice from you both and checking the sensor connector (and possibly the sensor itself - I have a friend with an R1100 in bits at the moment who is willing to swap out the sensor from his bike to check).

Here's hoping I don't actually have to pull the diff to bits!

Cheers, and thanks!
DaZZa is offline  
post #8 of 12 (permalink) Old Apr 25th, 2013, 4:20 am
Addict
 
Join Date: Mar 2004
Location: , , UK
Posts: 3,750
Those bullet connectors under the seat rail are located in the worst place to get wet. After I had cleaned mine thoroughly and removed all the green corrosion, I managed to find a large diameter sleeve to slide over for some extra protection. But you could wrap electricians tape around them to at least 1 inch past each end where the bullets fit in. PS they can be hard to separate. I started with needle nose pliers giving the wire a good pull. Concerned about stripping the wires, I was able to poke a fine screwdriver down to open up the outer circular contact a little to pull them out.

If you have to open up the RD you would have to make a judgement call on how loose the sensor ring is. If there was already some reasonable friction there I would clean up and re-use it. The problem with Loctite bearing fit is the metal to metal surfaces have to be thoroughly degreased before putting it on.

I don't know what the oem price is for the ring, if it is cheap then replace it. Many oem parts are pre-heated first to expand them, so check for this part. If you work sloppy and just tap it on the shaft, you may ruin their friction fit tolerance.

From what you said about the rain, I bet you have a connector problem. My speedo was always intermittent with the needle running wild up and down after the bike got wet, which is how I discovered this BMW design feature.



Never pay again for live sex! | Hot girls doing naughty stuff for free! | Chat for free!
voxmagna is offline  
post #9 of 12 (permalink) Old Apr 25th, 2013, 1:36 pm
Enthusiast
 
Join Date: Sep 2011
Location: Newport, Wales, United Kingdom
Posts: 273
Quote:
Originally Posted by voxmagna
From what you said about the rain, I bet you have a connector problem. My speedo was always intermittent with the needle running wild up and down after the bike got wet, which is how I discovered this BMW design feature.

Me too, I ended up removing the plug and permanently soldering the wires together and then shrink wrapping it, never saw a dodgy speedo again

Tim
------------------

2011 K1300GT
Special-K is offline  
post #10 of 12 (permalink) Old Apr 25th, 2013, 5:13 pm Thread Starter
Rookie
 
Join Date: Mar 2008
Location: Sydney, NSW, Australia
Posts: 37
Quote:
Originally Posted by voxmagna
Those bullet connectors under the seat rail are located in the worst place to get wet. After I had cleaned mine thoroughly and removed all the green corrosion, I managed to find a large diameter sleeve to slide over for some extra protection. But you could wrap electricians tape around them to at least 1 inch past each end where the bullets fit in. PS they can be hard to separate. I started with needle nose pliers giving the wire a good pull. Concerned about stripping the wires, I was able to poke a fine screwdriver down to open up the outer circular contact a little to pull them out.
I must have the freakiest BMW of this model in the country, because not only was I able to remove the connector easily, there was absolutely *no* sign of corrosion (or even of water, amazingly!) - in fact, the surrounding areas were still dusty from the last bush rally I rode it into (something I will never do again!).

No corrosion, but I will definitely be taking your advise about covering this one up once I fix the diff - shrink wrap, or decent waterproof tape will be going on for sure.

Quote:
Originally Posted by voxmagna
If you have to open up the RD you would have to make a judgement call on how loose the sensor ring is. If there was already some reasonable friction there I would clean up and re-use it. The problem with Loctite bearing fit is the metal to metal surfaces have to be thoroughly degreased before putting it on.
Well, I'm pretty sure I do - I got in there with a torch yesterday (it was the ANZAC day holiday here, after the dawn service I had a bit of time), and not only was the connector fine, I pulled the sensor out of the diff again and I could see the ring spinning independent of the wheel - hell, I could stick a screwdriver into the hole and spin the sender ring manually. - I'm 100% sure it's come loose.

Quote:
Originally Posted by voxmagna
I don't know what the oem price is for the ring, if it is cheap then replace it. Many oem parts are pre-heated first to expand them, so check for this part. If you work sloppy and just tap it on the shaft, you may ruin their friction fit tolerance.
Well, Max's and RealOEM quote less than $20 (US dollars, I assume) - just for laughs, I'm going to ring BMW and ask them how much it'd be - but I'll need to do the front seal of the diff at the same time (my mechanic friend noticed it was leaking a bit when he checked while we were out last weekend), but even including that, oil and loctite I don't reckon the parts will cost me more than $100 or so. The bit which is worrying me is the comments both posted about the bearing - but I guess I'll cross that bridge when I come to it.

Quote:
Originally Posted by voxmagna
From what you said about the rain, I bet you have a connector problem. My speedo was always intermittent with the needle running wild up and down after the bike got wet, which is how I discovered this BMW design feature.
I really wish you had been right, and it *was* just the connector - I could have been perfectly happy with replacing the BMW one with something generic which was more waterproof - but it looks like I'm out of luck on that one.

Thanks again for your input.
DaZZa is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the K-Bikes.com - Excellence in Motion forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
ABS issue on 2004 K1200RS congadude K1200RS/GT (Classic) 41 Oct 10th, 2012 10:32 am
My last 2 months and 2,600 miles on my 2002 K1200rs mrbill812 K1200RS/GT (Classic) 8 Sep 25th, 2012 11:22 am
Question on throttle response issue WMD K12/1300GT (Next Gen) 15 Oct 6th, 2008 1:50 pm
Suburban Machinery riser issue Falconfire K12/1300GT (Next Gen) 4 Aug 4th, 2007 10:01 pm
K1200RS UPSHIFTING Problem PaulK1200RS K1200RS/GT (Classic) 11 Jun 20th, 2006 12:55 pm

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome