K100 Upper Triple Tree on K75

zach_ross · 1 K100 Upper Triple Tree on K75 Mon Nov 17, 2014 3:47 am

zach_ross

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Does anyone know if you can do a direct swap from a K75 Upper Triple to a K100 Upper triple? I have a 87 K75S and am looking to replace the upper triple with one from a k100.

Rick G · 2 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 4:12 am

Rick G

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K75 forks are 41mm K100 are 41.3mm. It is usually considered that it is not an easy job as you cant tighten the clamping bolts enough to hold properly.
Why would you want to put K100 clamp on a K75. The K75 runs so smooth that the rubber mountings would serve no purpose and it turns the handlebars to jelly.

zach_ross · 3 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 4:18 am

zach_ross

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RicK G wrote:K75 forks are 41mm K100 are 41.3mm. It is usually considered that it is not an easy job as you cant tighten the clamping bolts enough to hold properly.
Why would you want to put K100 clamp on a K75. The K75 runs so smooth that the rubber mountings would serve no purpose and it turns the handlebars to jelly.

I have mounted clip-ons so the handlebar mounts are not necessary. I was under the impression that the forks on K75S are 41,3mm, also noticed that my 41mm clip-ons were not a perfect fit. Correct me if I am wrong

From one of your earlier posts

Seems as though 1987 K75S has same fork diameter as K100 until the late 80's

Rick G · 4 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 4:49 am

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Would you give me a link to that post as I can't ever remember seeing that document and I certainly haven't got it on my computer. Please don't get offended I am simply interested to know where it has come from.

zach_ross · 5 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 4:52 am

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RicK G wrote:Would you give me a link to that post as I can't ever remember seeing that document and I certainly haven't got it on my computer. Please don't get offended I am simply interested to know where it has come from.

No problem!

https://www.k100-forum.com/t6919-k75-forks

Inge K. · 6 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 5:24 am

Inge K.

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It seems like it have been too much smoking lately, Rick.

Rick G · 7 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 5:34 am

Rick G

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I would say that I got rid of that chart as possibly unreliable because as you can see by reading more of that thread there were many contradictions. That's best guess but when I get a chance I will have a look back through my backups.
Any how back to the original subject if the forks are the same diameter they will exchange OK but if not there is a problem with getting the clamps to tighten up enough.
One of the big problems I find is that there is so much published over the years, much of it has some contradictions so what is correct and what is wrong is very difficult to separate.

Rick G · 8 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 5:36 am

Rick G

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Inge K. wrote:~~It seems like it have been too much smoking lately, Rick.~~

zach_ross · 9 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 5:41 am

zach_ross

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Clear as mud . . . Shocked

so as long as my forks are 41,3mm the upper triple from a similar year should work?

Rick G · 10 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 6:24 am

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Ask Inge he's on line.

Inge K. · 11 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 7:08 am

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I don't think it would fit, because of the different bearing adjustement parts,
then you also must change the lower triple and the bearing adj. parts.

The 75 also have a steering damper at the stem which isn't present at the K100,
it might be some differences caused by this also.

BTW. Welcome to the madhouse.

zach_ross · 12 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 7:58 am

zach_ross

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Inge K. wrote:I don't think it would fit, because of the different bearing adjustement parts,
then you also must change the lower triple and the bearing adj. parts.

The 75 also have a steering damper at the stem which isn't present at the K100,
it might be some differences caused by this also.

BTW. Welcome to the madhouse.

Could you clarify which bearing adjustment parts you mean? As far as I can see the four things that need to match on the upper triple are; 1&2. fork distance and diameter, and 3&4. the center yolk hole and countersink depth for that. As long as those match up wouldn't it work? scratch

Inge K. · 13 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 8:13 am

Inge K.

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K75:

K100:

zach_ross · 14 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 8:30 am

zach_ross

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Inge K. wrote:K75:

K100:

Strange that they show it like that, I have mounting brackets for the handlebars on my upper tree...

Inge K. · 15 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 8:42 am

Inge K.

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zach_ross wrote:
Strange that they show it like that, I have mounting brackets for the handlebars on my upper tree...

They probably did smoke now and then at the drawing departement, too.

Rick G · 16 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 9:01 am

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The only thing that will prevent a changeover is, if the thread on #4 on both drawings is different and AFAIK they are the same.
I think Crazy Frog has a K75 top yoke on his K100 solo.

Inge K. · 17 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 9:27 am

Inge K.

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I think that the inside dia. on the knurled adjuster is different, and then it is a
stud on top and bottom of it at the K75...which goes inside the triple plate at
the top, and between the stem and the bearing at the bottom.

ReneZ · 18 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 9:29 am

ReneZ

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Seeing the names under that sheet with fork information it must have come from Flyingbrick.de.

Maybe the originators have an updated version? I think both Derbonner and Zonnenpfeile are members here (under different names Very Happy

)

Inge K. · 19 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 9:46 am

Inge K.

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Both derbonner and zonenfeile use the same names on this forum...........
What is wrong with the list?........I think it's the same that is found on FB today.

Inge K. · 20 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 3:07 pm

Inge K.

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Zachry!
After a bit more studying it looks like it shouldn't be any problem for you to use a K100 upper triple.
The early K75C using the same parts as the K100, but the same upper triple as the other K75 models with a F&S fork.

Which means that the protrusion at the top and bottom of the knurled adjuster nut later F&S K75's must have the same diameter as the top of the K100 steering stem.

zach_ross · 21 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 3:48 pm

zach_ross

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Inge K. wrote:Zachry!
After a bit more studying it looks like it shouldn't be any problem for you to use a K100 upper triple.
The early K75C using the same parts as the K100, but the same upper triple as the other K75 models with a F&S fork.

Which means that the protrusion at the top and bottom of the knurled adjuster nut later F&S K75's must have the same diameter as the top of the K100 steering stem.

Thanks Inge and everyone else for your help, I will order a triple tree upper and see if it fits. That is if there isn't one for sale in the forum?

Inge K. · 22 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 3:53 pm

Inge K.

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Try Duck: http://kbikeparts.com/

Motorworks have used parts, I'll guess the postage would be cheaper.

Why not try a advertisement on "blocket".

ReneZ · 23 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 7:16 pm

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RicK G wrote:I would say that I got rid of that chart as possibly unreliable because as you can see by reading more of that thread there were many contradictions.

There you go Inge.

Inge K. · 24 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 7:33 pm

Inge K.

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Haven't seen any, could be my glasses....

AL-58 · 25 Re: K100 Upper Triple Tree on K75 Wed Nov 19, 2014 7:16 am

AL-58

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I've got a K75s top triple clamp on my K100 sidecar. Had one on the last K100 sidecar too. Never had any problems fitting them. I couldn't tell you what year, I only ever looked for a 75s triple clamp. Much more direct steering for the sidecar.

Al

zach_ross · 26 Re: K100 Upper Triple Tree on K75 Sat Dec 27, 2014 7:38 am

zach_ross

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Number of posts : 50

Well now I have fit a top triple tree from a 1985 K100 on my 1987 K75 S, no problems fitting it at all. So good to know for future reference.

Thanks for all the tips and help.

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1 K100 Upper Triple Tree on K75 Mon Nov 17, 2014 3:47 am

zach_ross

2 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 4:12 am

Rick G

3 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 4:18 am

zach_ross

4 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 4:49 am

Rick G

5 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 4:52 am

zach_ross

6 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 5:24 am

Inge K.

7 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 5:34 am

Rick G

8 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 5:36 am

Rick G

9 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 5:41 am

zach_ross

10 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 6:24 am

Rick G

11 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 7:08 am

Inge K.

12 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 7:58 am

zach_ross

13 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 8:13 am

Inge K.

14 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 8:30 am

zach_ross

15 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 8:42 am

Inge K.

16 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 9:01 am

Rick G

17 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 9:27 am

Inge K.

18 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 9:29 am

ReneZ

19 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 9:46 am

Inge K.

20 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 3:07 pm

Inge K.

21 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 3:48 pm

zach_ross

22 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 3:53 pm

Inge K.

23 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 7:16 pm

ReneZ

24 Re: K100 Upper Triple Tree on K75 Mon Nov 17, 2014 7:33 pm

Inge K.

25 Re: K100 Upper Triple Tree on K75 Wed Nov 19, 2014 7:16 am

AL-58

26 Re: K100 Upper Triple Tree on K75 Sat Dec 27, 2014 7:38 am

zach_ross

27 Re: K100 Upper Triple Tree on K75

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