Gino, IT may be that your plate is too thick. Looking at another thread, it should be closer to 6.1mm and Sailor makes reference to a 6.5mm plate that the user could not use as it was too thick.
post #70 from this thread.
The quoted tread in message above is a bit long because of numerous back-forth including feedback from many members.
HOWEVER, the "bottom line" lesson(S) from this long older thread are:
- The regular OEM friction plate sold by BMW is generally 6 to 6.1 mm when NEW
- Most "reliable" sources like BeemerBoneYard will offer 2 models of Siebenrock after-market clutch friction plates (made in Germany). These have been measured by me and many members and are generally 6.1 to 6.18 mm MAX when new.
- Some cheaper alternatives, some on EBAY, are "made in China" and are generally 6.5 mm. A few members on the K1200RS forum and also here got caught buying these useless replacement...
- As the friction disc wears (gets thinner), it pushes the push-rod out more toward rear or transmission. The opposite, too thick friction plate, will bring it in (away from slave piston). This somewhat strange concept (depth -vs- plate thickness) has been explained many times by JZEILER (john) and is caused by curvature of diaphragm spring.
- Although BMW as never published a MAX friction disk thickness, various mistakes and measurements done by a member in the K1200RS forum leads to me to believe it is around 6.2 mm. More than this and you run out of push-rod extension in the slave cavity. Of course, one could install a longer push-rod to match a 6.5 mm friction plate... however, unless you are a machinist and have time to play guinea-pig, I fail to see why you would choose this battle. As designed, the slave cylinder and its piston inside has a limited travel based on normal wear range as specified in shop manual (6.1 new to 4.5 min when old). Unless you design a new slave and a new cavity in transmission, NOTHING can change this limitation.
- Once the transmission is in place (fully bolted) AND before installing you SLAVE, check distance / depth of push rod tip compare to metal in center of seal (see attached picture). You should have approx 16 to 18 mm. The attached photo show 19 mm, but this one had about 35K miles on this new friction disk (and as you know, push-rod goes out with wear...)
- Another tip, similar to above, if to measure space between slave and base of transmission as you tighten the 3 bolts of slave. With new plate installed, you should see a gap of at least 0.30 inch to approx max of 0.37 (3/8 inch). Of course, this resulting gap is proportional to previous item as a push-rod that is out more, will increase the gap measured here.
Buyer of clutch parts beware... hopefully every new K1200LT/RS member shopping for clutch parts will read this warning or the previous thread.