Honda Twins banner

1 - 3 of 3 Posts

·
Registered
Joined
·
256 Posts
Discussion Starter · #1 ·
I had this posted in a more specific forum, but it doesn't seem to be getting any visibility there, so I figured it might do better out here in the open. It probably has more interest to smaller bike owners anyway.

As I am building my project from the ground-up, I am collecting individual pieces as I go. Knowing dimensions of something you don't have in front of you could be helpful to someone along the line as they look for upgrades or replacements.

Let's call this a Fork Dimension Repository for data that we can collect as we dismantle and work with our own parts. If you have any of the details of your particular model, please post here and continue the thread. I made a quick graphic of a single fork leg with some variable dimensions on it. The AllBalls charts are great, as are the axle and fork tube lists, but they don't give you all of the info you might need for an upgrade or swap.



(A) is the fork tube diameter at the stem/triple tree mount. (B) is the fork travel or total throw of the fork tube inside of the assembled fork, without the spring inserted. (C) is the overall length of the fork tube or stanchion. (D) is the overall length of the extended fork, from top of the fork tube (not the nut) to the centerline of the axle.

I'll start with the forks that I am currently working on.


1974 Honda CB550/4
[HR][/HR]
Fork Diameter (A): Ø 35mm
Fork Travel (B): 110mm (4.333")
Fork Tube Length (C): 562mm (22.125")
Extended Fork Length (D): 711mm (28.000")
Axle Diameter (E): Ø 15mm

Fork Seal: 35mm x 48mm x 11mm (91255-300-033)
Stem Bearings:

  • Upper: 26 x 48.5 x 15.2mm needle bearing
  • Lower: 30 x 50 x 14.4mm needle bearing








If you have other forks and can take measurements, please don't hesitate to add to this list. I know somewhere along the line, this can help someone out with a swap or a replacement part.
 

·
Registered
Joined
·
256 Posts
Discussion Starter · #2 ·
Ok, I guess no one takes their stuff apart and measures everything like I do. :razz:


With that, can anyone at least give the "C" measurement of their CB or CL fork stanchions? Not aftermarket ones, but OE that came off of a bike. Post the year of the bike they came off of, too, if you can. I'm interested in knowing exactly how long the 350 forks are, and if they changed the dimensions at all through the run of the CB350s.

At the very least, an overall "D" dimension would be a big asset.




doug
 

·
Banned
Joined
·
426 Posts
1970 SL175 K0/K1

Fork Diameter (A): Ø 31mm [51410-313-020]
Fork Travel (B): 150mm (5.905")
Fork Tube Length (C):
Extended Fork Length (D):
Axle Diameter (E): Ø 15mm

Fork Seal: 31mm x 4mm x 10mm 91255-gaa-003] N.L.A.) [91255-110-003]
 
1 - 3 of 3 Posts
Top