Fork I.D help

[Noz]

Helloooo
I've started to pull apart this 550/4 chop and have come to the forks, which are longer than standard. They could be off the 750 but not sure. I've been thwarted by an aftermarket headlight rubber tube that's stuck to the stanchion and which I think will have to be cut off. I've undone the bottom of the fork leg and there's no bushes evident on the stanchion and the seal is proper wedged into the leg. I've undone the top and extracted the spring, which was upside down and appears covered in old crust. The stanchion is 35mm Diameter, the old seal is 8.5mm deep. There's a little bit of wear on the chrome in the travel and the other leg has bit of surface rust.  How do I I.d these forks please? Do you need a pic, measurements... your help would be greatly appreciated.

Another consideration would be to change them for another set of forks, what others are similar/will fit please? Cheers 

[K2-K6]

They look more or less standard,  but companies did sell longer stanchion for them to "convert" to this use.

I don't think any bikes from the era had anything that long,  hence the aftermarket supply probably.

[Noz]

I've measured the stanchion, it's 685mm / 68.5cm long, 35mm diameter. I've googling it and it's longer than the standard ones, it's a chop, so longer front end used.

https://www.hondatwins.net/threads/mechanical-dimensional-differences-between-cb450-cb500-cb550-and-cb750-forks.38001/

[K2-K6]

Yes, my grammar about standard.

Standard fork set (aluminium casting etc) but aftermarket supply could give you various lengths "over" for use on chops. Usually marketer as something like "3 inch over" "6 inch over" etc for whatever project you were doing.

Nothing to do with Honda or other manufacturer, just individual supply which you don't see now.

[Bryanj]

There are no bushes on 500/550 the internal parts will tell you what year the forks are.
Was there a threaded rod screwed into the top nut?

[Noz]

Pics... top cap, spring cap, spring, spacer tube, progressive spring with thin wedge at bottom of leg.

[Noz]

Fix or replace? Cheers for your help so far, I appreciate it 

[Noz]

Looks to be off a 550 not a 500.

If your reusing the fork stanchions then get them hard chromed by either Philpotts or Dynasurf. Both companies are very good, Philpotts get more business as they are better known, they do a postal service.

They are off a 550/4 f2 chop. I'll check those out, thanks for the recommendation 

[Noz]

I found a cast marking - 341, on the bottom leg which according to a google search is from the 750 k2. I need to get new piston seals on them too. Oh the joys of old bikes 

[Bryanj]

You would have to import long forks from the US and i rekon it wouldbe cheaper to let phillpots do them

[Trigger]

I found a cast marking - 341, on the bottom leg which according to a google search is from the 750 k2. I need to get new piston seals on them too. Oh the joys of old bikes 

Google is wrong. 341 relates to CB750 K3 to K6. You have a custom set of forks that was made up for a chopper style.

Stanchions on 550's are different lengths, depends if they are 550 K0, K1, K2 or F1 or F2 K3   

[Noz]

I found a cast marking - 341, on the bottom leg which according to a google search is from the 750 k2. I need to get new piston seals on them too. Oh the joys of old bikes 

Google is wrong. 341 relates to CB750 K3 to K6. You have a custom set of forks that was made up for a chopper style.

Stanchions on 550's are different lengths, depends if they are 550 K0, K1, K2 or F1 or F2 K3 

one letter out and it came from the sohc owners club forum post 

[Trigger]

I found a cast marking - 341, on the bottom leg which according to a google search is from the 750 k2. I need to get new piston seals on them too. Oh the joys of old bikes 

Google is wrong. 341 relates to CB750 K3 to K6. You have a custom set of forks that was made up for a chopper style.

Stanchions on 550's are different lengths, depends if they are 550 K0, K1, K2 or F1 or F2 K3 

one letter out and it came from the sohc owners club forum post 

A lot of false info on SOHC.Net    341 relates to CB750 K2, K3, K4, K5, K6 as a bike but, the K2 forks are 300 

[Bryanj]

Disc brake 450's also had 341 sliders but with 500 stanchions

[Noz]

Cheers y'all    I suspect this project will be up for sale soon, hopefully.. what a headache!