BMW K1200, K1300, and K1600 Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #1
Hi all and thanks for letting me join in the forum. I am in the middle of replacing the clutch plate on a 1997 K1200RS and have came across an issue. It’s not my bike so I can’t tell how the bike was before I started work on it. My problem is that when everything is rebuilt and the slave bled properly I can only pull the clutch lever half way before I get a solid lever. It’s not disengaging the clutch correctly and will still move the rear wheel when the lever is pulled. I have had the box off and on numerous times and it is built correctly as far as I can tell. New o-ring and nut used for reassembly. Has anyone ever came across this before or has anyone any ideas as to why this may be happening. I did ride the bike into the workshop before dismantling and the clutch lever went in the full way no problem. Thanks in advance
 

·
Registered
Joined
·
1,804 Posts
All new OEM parts that is including the metal friction plates/spring and a friction disk to factory spec of 6mm.

Or just a cheap friction disk replacement with some foreign made fleabay part and no new metal plates to replace the possibly dished in OEM parts?
 

·
Registered
Joined
·
519 Posts
Hi all and thanks for letting me join in the forum. I am in the middle of replacing the clutch plate on a 1997 K1200RS and have came across an issue. It’s not my bike so I can’t tell how the bike was before I started work on it. My problem is that when everything is rebuilt and the slave bled properly I can only pull the clutch lever half way before I get a solid lever. It’s not disengaging the clutch correctly and will still move the rear wheel when the lever is pulled. I have had the box off and on numerous times and it is built correctly as far as I can tell. New o-ring and nut used for reassembly. Has anyone ever came across this before or has anyone any ideas as to why this may be happening. I did ride the bike into the workshop before dismantling and the clutch lever went in the full way no problem. Thanks in advance
YES we have seen this before - BOTH on the old (now closed) K1200RS forum on "www.I-BMW.com" AND ALSO on the K1200LT forum on www,BmwLt.com.

THE SHORT AWSWER IS THIS: You will have to open the clutch again and take measurements of new friction plate you bough AND the pressure plate you are using (old or new).

THE LONG ANSWER IS there are 2 "potential" problems / reasons that may cause this:

1) On EBAY and a few other site, they sell cheap "after-market" clutch friction plate that is more than 6.1 mm thick. This is not allowed based on the BMW specs where a new OEM friction plate (made by SACHS) is normally 6 mm. Most after-market disc are OK and are within specs, but not the cheap "made in China" friction disc without any brand or stamps on the disc - I have seen some as thick as 6.5 mm.

Because of the design of the clutch pack and the curvature of the Diaphragm spring, any friction plate more than 6.1 will cause the push-rod to be shorter at exit of the transmission (into slave). Although this sounds counter to common logic, you have to understand the design of the clutch pack - in fact BMW does warn you indirectly by saying in the owners manual that the fluid level in the clutch master (at handlebar) will go up as the clutch wear (meaning the push rod goes out more into the slave when the friction plate is thinner).

2) the 2nd issue is specific to early models of the K1200RS (1997 in Europe/Canada and some 1998 in USA): On the early models, BMW has used a thicker Pressure-Plate (see attache photo for measurements AND part numbers). All other models (mid 1998 to end of production) have the newer / thinner Pressure-Plate with a different part number.

The old thicker Pressure-Plate AND the old thinner friction-Plate (was matching pair) are BOTH obsolete and are no NO LONGER available in parts fiche. So if your 1997 models has the older / thicker Pressure-Plate (check my photo measurements), you need to buy a new Pressure-Plate that should match the new specs. If you choose to buy a used Pressure-Plate you do not know what you are getting: both in terms of thickness AND in terms of surface damage...

I do not know where you are based, but MotorWorks in UK has very good prices for these clutch parts. They sell mainly the SACHS parts that are in fact exact equivalent to OEM (factory was using SACHS). Even with shipping cost, I can get them shipped to my place in Canada for much less than most suppliers / dealers in USA.
https://www.motorworks.co.uk/vlive/Shop/Parts.php?T=5&NU=15&M=45&Ct=CA&SbCt=BA_15_45_CA_30
 

Attachments

·
Registered
Joined
·
5 Posts
Discussion Starter #4
Hi all and thanks for letting me join in the forum. I am in the middle of replacing the clutch plate on a 1997 K1200RS and have came across an issue. It’s not my bike so I can’t tell how the bike was before I started work on it. My problem is that when everything is rebuilt and the slave bled properly I can only pull the clutch lever half way before I get a solid lever. It’s not disengaging the clutch correctly and will still move the rear wheel when the lever is pulled. I have had the box off and on numerous times and it is built correctly as far as I can tell. New o-ring and nut used for reassembly. Has anyone ever came across this before or has anyone any ideas as to why this may be happening. I did ride the bike into the workshop before dismantling and the clutch lever went in the full way no problem. Thanks in advance
YES we have seen this before - BOTH on the old (now closed) K1200RS forum on "www.I-BMW.com" AND ALSO on the K1200LT forum on www,BmwLt.com.

THE SHORT AWSWER IS THIS: You will have to open the clutch again and take measurements of new friction plate you bough AND the pressure plate you are using (old or new).

THE LONG ANSWER IS there are 2 "potential" problems / reasons that may cause this:

1) On EBAY and a few other site, they sell cheap "after-market" clutch friction plate that is more than 6.1 mm thick. This is not allowed based on the BMW specs where a new OEM friction plate (made by SACHS) is normally 6 mm. Most after-market disc are OK and are within specs, but not the cheap "made in China" friction disc without any brand or stamps on the disc - I have seen some as thick as 6.5 mm.

Because of the design of the clutch pack and the curvature of the Diaphragm spring, any friction plate more than 6.1 will cause the push-rod to be shorter at exit of the transmission (into slave). Although this sounds counter to common logic, you have to understand the design of the clutch pack - in fact BMW does warn you indirectly by saying in the owners manual that the fluid level in the clutch master (at handlebar) will go up as the clutch wear (meaning the push rod goes out more into the slave when the friction plate is thinner).

2) the 2nd issue is specific to early models of the K1200RS (1997 in Europe/Canada and some 1998 in USA): On the early models, BMW has used a thicker Pressure-Plate (see attache photo for measurements AND part numbers). All other models (mid 1998 to end of production) have the newer / thinner Pressure-Plate with a different part number.

The old thicker Pressure-Plate AND the old thinner friction-Plate (was matching pair) are BOTH obsolete and are no NO LONGER available in parts fiche. So if your 1997 models has the older / thicker Pressure-Plate (check my photo measurements), you need to buy a new Pressure-Plate that should match the new specs. If you choose to buy a used Pressure-Plate you do not know what you are getting: both in terms of thickness AND in terms of surface damage...

I do not know where you are based, but MotorWorks in UK has very good prices for these clutch parts. They sell mainly the SACHS parts that are in fact exact equivalent to OEM (factory was using SACHS). Even with shipping cost, I can get them shipped to my place in Canada for much less than most suppliers / dealers in USA.
https://www.motorworks.co.uk/vlive/Shop/Parts.php?T=5&NU=15&M=45&Ct=CA&SbCt=BA_15_45_CA_30
It’s a TRW clutch measured at 6mm with callipers. I will research more in the morning. Thank you for your help so far.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #5
All new OEM parts that is including the metal friction plates/spring and a friction disk to factory spec of 6mm.

Or just a cheap friction disk replacement with some foreign made fleabay part and no new metal plates to replace the possibly dished in OEM parts?
It’s a TRW plate measuring 6mm.
 

·
Registered
Joined
·
519 Posts
It’s a TRW clutch measured at 6mm with callipers. I will research more in the morning. Thank you for your help so far.
Of course, TRW is a good aftermarket clutch friction plate and if not part of the cheap "Made in China" I was referring to.

This item being OK, you ALSO need to measure carefully the Pressure-Plate being used based on my photo. ALSO check the part number stamped on your Pressure-Plate to compare to my earlier photo (text added at bottom of photo).

As a final hint that something is not properly assembled ..OR.. some parts are out of specs, JUST when you are ready to install the SLAVE with transmission all bolted:
the measurements of the clutch push-rod section visible out of the transmission shaft (where it slides into) should not be less than 16 mm. Measured from outmost edge of the shaft (into slave cavity) to tip of push-rod.

When the friction plate is worn to thinnest (4.5 min spec) , this measurement increases up to a maximum of approx 25mm - this is why by design the Slave piston can move fairly deeply to accommodate this movement cause by wear of friction plate (and also why fluid level goes up at handlebar with wear).
 

·
Registered
Joined
·
5 Posts
Discussion Starter #7
It’s a TRW clutch measured at 6mm with callipers. I will research more in the morning. Thank you for your help so far.
Of course, TRW is a good aftermarket clutch friction plate and if not part of the cheap "Made in China" I was referring to.

This item being OK, you ALSO need to measure carefully the Pressure-Plate being used based on my photo. ALSO check the part number stamped on your Pressure-Plate to compare to my earlier photo (text added at bottom of photo).

As a final hint that something is not properly assembled ..OR.. some parts are out of specs, JUST when you are ready to install the SLAVE with transmission all bolted:
the measurements of the clutch push-rod section visible out of the transmission shaft (where it slides into) should not be less than 16 mm. Measured from outmost edge of the shaft (into slave cavity) to tip of push-rod.

When the friction plate is worn to thinnest (4.5 min spec) , this measurement increases up to a maximum of approx 25mm - this is why by design the Slave piston can move fairly deeply to accommodate this movement cause by wear of friction plate (and also why fluid level goes up at handlebar with wear).
I’m in the UK in Northern Ireland and use Motorworks quite often. I’m making sense of this now. I imagine as the bike is a 97 model the pressure plate is thicker and not accommodating the new styles of friction plate etc. So I need to basically buy a complete set up to the latest spec after measuring so it’s a complete unit all within the new tolerance. Thanks for your help so far. I’ve been tearing my hair out as it is all built as you would expect and not making sense.
 

·
Registered
Joined
·
519 Posts
I’m in the UK in Northern Ireland and use Motorworks quite often. I’m making sense of this now. I imagine as the bike is a 97 model the pressure plate is thicker and not accommodating the new styles of friction plate etc. So I need to basically buy a complete set up to the latest spec after measuring so it’s a complete unit all within the new tolerance. Thanks for your help so far. I’ve been tearing my hair out as it is all built as you would xpect and not making sense.
In April-1998, BMW had published a Service-Bulletin about the change of pressure-plate thickness and the need to fit both new parts together when a repair was needed (thinner Pressure with thicker friction plate). However by now, most staff of this era working a BMW dealers are either retired or too young to be aware of such issues affecting only 1997-1998 models. OF COURSE the Service-bulletin did not warn you of the final symptoms that would see if indeed you had the wrong combo of clutch part thickness. For the USA market, the cutoff / change of design at factory was on all K1200RS built after 12/1997.

Do NOT buy anything before you take measurements of Pressure-Plate AND look for the part number stamped in metal (as described in my photo).

Do NOT make the common mistakes that I often see on forums and jump to conclusion or assumptions... I have seen this problem before caused by the 2 issues that I have described in my earlier post, HOWEVER your case could be different with something else not mounted properly. Investigate, get the facts and then proceed with parts IF NEEDED.

BY THE WAY, I hate to bring more bad news, but by bottoming out the Slave in your 1st test, you may have damaged it. The hydraulic pressure can be strong enough to bent the circlip holding the piston in place. On all clutch rebuild for K1200RS/LT, I generally suggest a new Slave as they tend to fail after 60,000 miles on average (unless the trust bearing is re-greased at 30,000 miles interval max).
 

·
Registered
Joined
·
5 Posts
Discussion Starter #9
I’m in the UK in Northern Ireland and use Motorworks quite often. I’m making sense of this now. I imagine as the bike is a 97 model the pressure plate is thicker and not accommodating the new styles of friction plate etc. So I need to basically buy a complete set up to the latest spec after measuring so it’s a complete unit all within the new tolerance. Thanks for your help so far. I’ve been tearing my hair out as it is all built as you would xpect and not making sense.
In April-1998, BMW had published a Service-Bulletin about the change of pressure-plate thickness and the need to fit both new parts together when a repair was needed (thinner Pressure with thicker friction plate). However by now, most staff of this era working a BMW dealers are either retired or too young to be aware of such issues affecting only 1997-1998 models. OF COURSE the Service-bulletin did not warn you of the final symptoms that would see if indeed you had the wrong combo of clutch part thickness. For the USA market, the cutoff / change of design at factory was on all K1200RS built after 12/1997.

Do NOT buy anything before you take measurements of Pressure-Plate AND look for the part number stamped in metal (as described in my photo).

Do NOT make the common mistakes that I often see on forums and jump to conclusion or assumptions... I have seen this problem before caused by the 2 issues that I have described in my earlier post, HOWEVER your case could be different with something else not mounted properly. Investigate, get the facts and then proceed with parts IF NEEDED.

BY THE WAY, I hate to bring more bad news, but by bottoming out the Slave in your 1st test, you may have damaged it. The hydraulic pressure can be strong enough to bent the circlip holding the piston in place. On all clutch rebuild for K1200RS/LT, I generally suggest a new Slave as they tend to fail after 60,000 miles on average (unless the trust bearing is re-greased at 30,000 miles interval max).
Hey. You have been an absolute star. Old plate ended in 570 so new parts in today and we are all sorted. Life saver. Just the mega rebuild of the back end to do now. Thanks so much.
 

·
Registered
Joined
·
519 Posts
Hey. You have been an absolute star. Old plate ended in 570 so new parts in today and we are all sorted. Life saver. Just the mega rebuild of the back end to do now. Thanks so much.
Well... I think we need to ALSO thank my friend who posts here as alias "H96669". Many years ago, on the now closed "www.I-BMW.com" forums, he is the one that brought up this Service-Bulletin when a similar issue showed up.

Later on, I did get the measurements and part number from another of the member (on same forum) doing a clutch job on a 1997 models.
 

·
Registered
Joined
·
1,804 Posts
Thanks Jean....I still have a copy of that bulletin at home if you need it.And probably a copy of all the service bulletins related to the K1200RS.

Mind you the 97/year from the first post?Years ago that would have clued me in right away and I would have mentioned the bulletin or copy/pasted it.Slowing down I guess.....:sad
 
1 - 11 of 11 Posts
Top