Honda CB750 Sandcast

The Restoration Shop => Front End and Suspension => Topic started by: UK Pete on May 08, 2014, 12:52:31 pm

Title: fork damper valve
Post by: UK Pete on May 08, 2014, 12:52:31 pm
Can somebody tell me which way the fork damper valve goes, does the taper face upwards or down, also same for the fork piston does the recessed end go at bottom or top?
(http://cb750sandcastonly.com/coppermine/albums/userpics/10004/Capture_ko_fork_internals.JPG)
pete
Title: Re: fork damper valve
Post by: hondasan on May 08, 2014, 03:29:16 pm

A good question - I don't recall seeing a clear diagram to categorically answer this. One of the parts list diagrams appears to show the piston recess at the top, but gives no clues for the damper valve.
From memory, my recollection is that the recessed edge of the piston is indeed at the top, and taper of damper valve at the bottom (in fact, I have a feeling that with the various circlips and snap ring in their correct places that it may only go together if as above).
I'm sure others will share their views, and hopefully confirm.

Cheers - Chris R.
Title: Re: fork damper valve
Post by: Steve Swan on May 08, 2014, 04:22:44 pm
sheesh.  i can't remember!  Probably Mark B. would know, since he probably has some forks apart right now !
Title: Re: fork damper valve
Post by: 4pots1969 on May 08, 2014, 04:25:01 pm
It is the chamfer upward for the Photo 1
Low of the ring towards the chamfer (TOP) of the piston for the photo 2  (Error from me rectified on the photo 2)

Taken information about two old assembled tubes


Title: Re: fork damper valve
Post by: markb on May 08, 2014, 05:46:58 pm
I know I have notes somewhere about this but I think Gerard is correct.  As I recall it seems like one of the rings #3 & 4 in the original post had something different on one side.  Maybe it was just that one was thicker.   :-\  I know they are different and maybe they will only go one place but I would check closely.
Title: Re: fork damper valve
Post by: UK Pete on May 10, 2014, 01:31:58 pm
Ok it occurred to me today that i have a spare set of sandcast/k0 forks so i took them apart to see how they go together, here are the photo's
so it is recess on piston upwards, chamfer on valve downwards, hope this helps others
pete
(http://cb750sandcastonly.com/coppermine/albums/userpics/10004/001%7E8.JPG)
(http://cb750sandcastonly.com/coppermine/albums/userpics/10004/002%7E4.JPG)
(http://cb750sandcastonly.com/coppermine/albums/userpics/10004/003%7E8.JPG)
(http://cb750sandcastonly.com/coppermine/albums/userpics/10004/004%7E5.JPG)
Title: Re: fork damper valve
Post by: Rddmm2 on November 19, 2018, 05:52:18 pm
I'm replacing fork seals which are weeping a bit. KO Vin 10068**
I read a warning by Hondaman in his book not to remove bottom fork allen bolts because of reassembly issues.  I'd like to clean up lower internals, but not sure if that's possible with KO forks?   Thanks. 
Title: Re: fork damper valve
Post by: bojje on November 19, 2018, 06:07:25 pm
Hi!
From VIN it looks you have a pretty early K1. To dissasemble these just dismount circlip, drain oil, and push lower forkleg to dissasemble. Might be hard to push off, use gloves. The bottomscrew at lower forkleg needs dismount at first at late -73 years model, with newer frontfendermount.
Good Luck, Bo from Sweden.
Title: Re: fork damper valve
Post by: Rddmm2 on November 24, 2018, 08:28:16 pm
Thanks.  I removed cir clip, and pulled upper section from the fork bottom.  Then I removed allen bolt on bottom of fork so I could remove lower pipe for cleaning.  Reassembled with fresh oil.