Honda drum brake steel liner

[AshimotoK0]

Got three of the CB250/350 K front drum hubs  with the extra 'blind' spoke holes in, specific to K0/K1 models plus one later one without 'blind holes'. Problem is one K0 one has a cracked liner. Anyone know how to remove the cracked one and is it possible to swap them, as the later front hub one is fine. I do have access to a lab oven that goes to 450 degrees Centigrade . Other alternative it to CNC the 'blind' holes in the later one. You can spot that the drum is incorrect a mile off on a K0/1 . I think cracking was a common problem, I know my 250K2 suffered it back in the day. That K0 on 'Man Lab' that James May swapped with DS for his museum has the wrong front hub fitted BTW, probably for that reason.

Ash

Here is a library picture of the hub with 'blind holes'

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[Bryanj]

I have a feeling that the hub is cast round the liner so swoppingone to another won't work, but on here somewhere is the address and number for a man in huddersfield who will machine out the old liner and shrink in a new liner then machine to size---he did several 500/550 rear for me quite cheap as i was in no rush.

I would not do this for a "Racer" as its possible for the liner to move if got very hot but i doubt very much you will do that to yours Ash

Found it

Paul Jackson Huddersfield near Junction 23 M62

01422 378100

[AshimotoK0]

I have a feeling that the hub is cast round the liner so swoppingone to another won't work, but on here somewhere is the address and number for a man in huddersfield who will machine out the old liner and shrink in a new liner then machine to size---he did several 500/550 rear for me quite cheap as i was in no rush.

I would not do this for a "Racer" as its possible for the liner to move if got very hot but i doubt very much you will do that to yours Ash

Found it

Paul Jackson Huddersfield near Junction 23 M62

01422 378100

Cheers Bryan.. you have answered another question as there is alloy flashing around the exposed circumference of the liner so yes cast in.
Will weigh up the pros and cons of drilling blind holes versus  repair of K0 one. Yea not much likelihood of me doing any racing 

There used to be a guy I dealt with for medical flow straighteners for air, based  in Leicestershire, I think,  and his sideline was replacing Honda drum liners .. can't remember his name though and that was about 18 years ago! His surname may have been James.
Ash

[matthewmosse]

When you machine the liner out you find it has a regular patterned profile in the liner casting and deffinately the hub is cast round that. I did my own hub re lining on cb500 and relied on the heat expansion + contraction of freezing the liner and heating the hub with an acetalene torch whilst it was spinning in the lathe. Then I pressed them together using the tailstock as a press. As the liner is actually a bit bigger than the hub and likely to get expand if hot in use I doubt there is any danger of the liner comming loose. Rather furtunately the lathe was on its limmits so the finish on the liner was rough too thanks to some lathe judder. I have seen a belt and braces approach used by others doing this job where they drilled down the joint in 3 places and inserted grub screws so 50% was in the alloy and the other 50% was in the liner, this might also have been used during istallation much like a taper locking centre on industrial sprocketts or v belt pullies.