Fork tube length ?

[grewth]

Can anyone please tell me the correct length of the inner fork tubes for the CB750F1 please ?

 

[grewth]

After doing some research, the smart money seems to be on 580mm for the tubes, with an overall fork length of 753mm axle centre to top face.
Apparently the CB750F2 has 585mm tubes, same 35mm diameter.
And I just happen to have a pair that I've got no use for.
No idea if they can be mixed with F1 parts.
But I'll soon be finding out

 

[Loki]

Bit of a sore point for me this one after I sent my legs off for hardchroming and the company seems to have gone bust, these fork tubes are indeed 580mm x 35mm, I currently have K6 forks on mine so I can move it around, the F1 fork stanchions are like hens teeth, new ones are manufactured in Italy but are about £400 each!!
The other aspect is the diameter of the bore in the bottom of the leg for the oil stop which is different to the K model forks, one of the US CB750 forums has a table of part numbers and dimensions for cross reference but nothing crosses with the F1, another unique part.
I did put up a question on this forum a few months back, don't know if you've seen it?

Loki

 

[grewth]

Bit of a sore point for me this one after I sent my legs off for hardchroming and the company seems to have gone bust, these fork tubes are indeed 580mm x 35mm, I currently have K6 forks on mine so I can move it around, the F1 fork stanchions are like hens teeth, new ones are manufactured in Italy but are about £400 each!!
The other aspect is the diameter of the bore in the bottom of the leg for the oil stop which is different to the K model forks, one of the US CB750 forums has a table of part numbers and dimensions for cross reference but nothing crosses with the F1, another unique part.
I did put up a question on this forum a few months back, don't know if you've seen it?

Loki

Cheers Graham !
I'll look up that post of yours as soon as I have time.
When I was comparing stuff the other day I found out that the tubes in the F2 forks that I've got are 585mm long with very similar looking top plugs.
Dunno if it would be possible to build up a hybrid fork using F1 sliders on F2 tubes ?
Having said that the F2 forks I've got aren't in brilliant condition anyway, with some rust pitting too.
I'm also thinking that CB550F sliders might be the same as the F1, at 352mm long.
It might be easier/cheaper to source 550 parts instead.

 

[Loki]

F2 tubes might fit but you might need the matching oil locks doubt if the 5mm difference will be noticeable.

Loki

 

[grewth]

F2 tubes might fit but you might need the matching oil locks doubt if the 5mm difference will be noticeable.

Loki

I wonder if the F2 oil locks might swap over too ?
I guess that at some point machining will be required and that equals £££££ unless you happen to have a tame pet machinist.
Alternatively, if you have tubes that are the right dimensions at the bottom end, but are just too long, it would be possible to have the top end shortened and new threads cut for the top bungs.
Again maybe expensive but it would work.