Are all Dura Ace Headsets JIS?

I have an NJS, but need a 26.4 ISO crown race. Please advise.

I would have thought so, but then what do I know.

Post usefulness rating - 2.1

i had a 26.4 but it was ISO

shim it, my advise is to use Rubicon cans, much thinner metal than coke cans, full NJS

:)

i had a 26.4 but it was ISO

^^ This is what I need. Not sure what the JIS size is. Silly pillock that I am, now my build has to wait.

JIS is 27

shim or file down as needed.

Dowh! No Roberts for me this week then : (

shim or file down as needed.

I would rather put the right part in.

what if there is paint on the race and it still won't fit?

I got a call from Roberts Cycles this morning, saying that they could not fit the headset I supplied to my new frame, because the crown race size should be 26.4 ISO not 27.0 JIS (thanks Murt). I bought the JIS headset in error (in ignorance actually).

I had the right part ordered originally, but it got lost by Royal Fail. Being the impatient idiot that I am, I bought a replacement from Japan, because the price was about the same for one with an NJS stamp on it, as it was for one sourced in the UK.

Moral of the story. Have patience grasshopper and do your research.

FAIL FAIL

You can get an NJS headset @ 26.4mm from Tange Seiki via Freshtripe, I just fitted one, it's very light and nicely made.
DS

if your trying to get a bearing race of 27.0 onto a fork with a 26.4, then there is nothing stopping you getting a shim machined up at 0.3 mm thick to make up for it.

honestly its possible to even machine down the bearing race itself (not the fork) but i think the shim is the best option.

coke can will work if its maybe a bit too thick. no harm in trying the shim method.

You can get an NJS headset @ 26.4mm from Tange Seiki via Freshtripe, I just fitted one, it's very light and nicely made.
DS

I got a replacement Dura Ace 26.4 (non NJS), but that looks like a good option to bear in mind. Thanks.

Link to the Tange headset
http://www.freshtripe.co.uk/Freshtripe/Oily%20Bits.html

nooooooooo, not njs???????????

:)

njs is for losers.

sorry, you've lost me there

Oi! Shut it you lot!

ha!

ha!

ha!

So, when will the Roberts be built and in your possession?

There's a place in the Bike Porn thread reserved for it.