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1985 K100RS steering stem bearings.

mcmlcccvrs

New member
I installed new steering head bearing and races earlier today and came across this in the parts fiche. Item 2 is a circlip. It is shown in the parts fiche for K75C and all K100 models but not the 4V K100RS.

Parts fiche.jpg

My bike doesn't have one. I have seen these lower fork bridges for sale on eBay and there was no visible circlip on the underside of those either. It's not for the brake pipe as it is held on at the top with a nut. So what is this for?



Steering head.jpg
 
Doesn't your picture show a steel piece in the triple clamp hole that looks sort of like a snap ring? Item 2. Beware that German to English translations don't always use words that Americans would use if they were writing the parts lists.


When I did my bearing replacement, I learned that the knurled top nut had to be really tightened and then "no hands" riding was possible at all speeds, any wobble was gone.
 
The steel shaft is a press fit into the lower aluminum triple clamp. My guess is that the originals were over-engineered and field experience showed that the snap ring was not needed. The steel shaft cannot move downward after it is installed in the frame steering neck with the upper triple clamp and top nut.

Frank
 
The steel shaft is a press fit into the lower aluminum triple clamp. My guess is that the originals were over-engineered and field experience showed that the snap ring was not needed. The steel shaft cannot move downward after it is installed in the frame steering neck with the upper triple clamp and top nut.

Frank

I can't say about the latest models but that ring is there for a reason on earlier models. The lower steering head bearing is located on a slight shoulder on the stem. Factory manual instructions for removal of this bearing are to press the stem downward until the bearing is free of the shoulder at which point it can be simply lifted off the stem.

Installation calls for pressing the stem back in place in the triple tree until it contacts that snap ring, followed by pressing the bearing back on the shoulder on the stem. It urges caution to make sure the notch for the steering head lock is correctly positioned.

All that sliding around, even in a press fit would not give me warm fuzzies without the snap ring or other stop. They could of course accomplish the same thing with a large stop machined on the end of the stem.
 
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