K75 Fork Internals

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Nourish
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Joined: Tue Aug 10, 2010 5:15 am
Location: Bristol, UK

K75 Fork Internals

Post by Nourish »

I have just purchased a pair of used K75S fork legs and have pulled them apart for inspection and have enclosed a couple of pictures of the left hand one. The very light spring on the valve is accompanied by two O rings and one of them is wrapped around the spring - I can't believe that this is correct - where should these two rings fit? and secondly the two large compression springs have a nylon spacer between them and a slightly larger on e at the very top - the parts fiche shows only one spacer - what is correct? These forks are going to be fitted to my naked R100 and came from a faired bike so some adjustment will be needed for to the ride height. Thanks for your thoughts.

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Major Softie
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Joined: Tue Aug 03, 2010 1:46 pm

Re: K75 Fork Internals

Post by Major Softie »

Well, two things.

First of all, you know there were two different K75 forks, right? Showa and (I believe) Sachs. So, you have to be looking at the right parts fiche for those forks.

Second, there were many spring kits available for the bike from the aftermarket, so you can't assume anything about how the springs are supposed to be arranged.
MS - out
Nourish
Posts: 194
Joined: Tue Aug 10, 2010 5:15 am
Location: Bristol, UK

Re: K75 Fork Internals

Post by Nourish »

Thanks for the reply Major, these leg bottoms are Brembo and were cast in 1985. Cheers
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Jeff in W.C.
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Location: Walnut Creek, CA

Re: K75 Fork Internals

Post by Jeff in W.C. »

the internals look similar to my forks on my 88 R100 RT. I do believe one of those O-rings goes in the grove on that piece just to the left of the small spring in your photo.
Jeff in W.C.
1988 R100 RT
2018 R1200 GS
"I've got my motorcycle jacket, but I'm walking all the time." Joe Strummer/Clash
Nourish
Posts: 194
Joined: Tue Aug 10, 2010 5:15 am
Location: Bristol, UK

Re: K75 Fork Internals

Post by Nourish »

Thank you Jeff - I think your right - So what do they do?
In case any one wants to make a note The Sachs stanchions measure 1.627" and the Showa ones 1.612" - I have the Sachs ones. Cheers
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Jeff in W.C.
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Joined: Tue Aug 03, 2010 9:20 am
Location: Walnut Creek, CA

Re: K75 Fork Internals

Post by Jeff in W.C. »

Nourish wrote:Thank you Jeff - I think your right - So what do they do?
In case any one wants to make a note The Sachs stanchions measure 1.627" and the Showa ones 1.612" - I have the Sachs ones. Cheers
I believe those parts make of the valve portion of the damper, but I'm really not an expert here. Hopefully someone with more knowledge will speak up confirming or correcting my statement.
Jeff in W.C.
1988 R100 RT
2018 R1200 GS
"I've got my motorcycle jacket, but I'm walking all the time." Joe Strummer/Clash
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