Hi, taken off the forks from my Bianchi road bike so that I can fit a new headset. managed to get everything off and then I was left with the forks with this metal rim attached. Is it supposed to be there?? I dont think so.

Anyway, I banged it off with force and there was still a ridge underneath it.... so the bottom of the headset doesn't go flush to the crown of the forks and thus not enough thread pops through the top to screw the top of the headset on to.




So, I decided I'd try and sand down the ridge so that the bottom of the headset sits right down on the crown.... Is this the right thing to do? I'm a little worried that a modern cartridge headset wont go onto an old fork. Help....

xx

the crown race might be the wrong size.

there are two sizes for 1" steerers.

calipers out and measure, do not take down the shoulder of the forks

Well, I started sanding but gave up. How do I find out the correct size of headset I need? I can't find any info on crown race on any headset listings at online stores

looks like you have 27mm seating point on the fork, and the shimano crown race is 26.4

bike shops/frame builders might mill the fork down for you, if shimano don't do a 27mm race for that headset

shall I carry on sanding?

yes, you do remove the crown race.

but you need to fit the new one, which needs to be the right size.

don't fuckin sand the steerer! you won't get it even and the crown race will end up loose, or ovalled.

http://www.sjscycles.co.uk/product-Shimano-Shimano-HP-M563-fork-crown-race-27.0mm-1-inch-(22.2)-15210.htm

you have to do the hard work on shimano's site and get the part number for the headset you're using.

Yep that where the crown race should fit on. Italians are awkward fuckers and go with a slightly non standard standard. Check Sheldon for the the headset details.

http://www.sheldonbrown.com/cribsheet-headsets.html

Good stuff guys!

Will that crown race from SJS just fit into the bottom of my headset or will I need a whole new set?

OK, found the tech sheet on shimano website here and it says it's 27mm like the frame, but that you are to use a press to fit the lower cone cover

I think you should be able to just buy that crown race, but give them a ring just incase they are pretty helpful at sjs.

ok, cool

failing that, tekk it to a bike shop and let THEM sand down the ridge.

....yeah, i hear BLB have some modern sanding apparatus ;-)

Even on 26.4mm seating and 26.4mm crown race I.D. interference fits the crown needs to be pressed on with some force.

What I am saying here is that you may have the right size crown race - take it to your LBS and see if they can use their race seating tool to put it on.

On a second look I think u might be right. I have a friend with a press.... I'm not spending £50-60 to have it fitted. I think it just needs to be forced on. I measured the CR on my headset and it's 27mm

£60 ! were you thinking of getting the Queen to do it !?

The last time I needed a race pressed onto a crown a few months back, I took the fork and race to my local bike shop and they did it in 30 seconds for free.

I imagine if they do charge it couldn't be much more than a fiver ?

Hi, here's what you need to do ...

Get thee down to a good bike shop. There, they can accurately measure the external diameter of the flange on the fork crown that you want to fit your lower race to. If they are really a good, old-school bike shop, they'll have a fork crown race cutter, and if the fork crown is oversize relative to your crown race, they can accurately & concentrically (so the headset bearing runs properly) shave material off to the right, slightly oversize diameter. The crown race should be no more than 0.2mm greater external diameter than the internal diameter of the crown race - this is the generally accepted degree of "interference" required in this type of interference fit.

Don't just try and whack the thing on with a heavy tube hammer / crown race fitting tool (or let anyone else try the same) as there's a fair chance they'll split the race, and then you will be in schtuk ... Shimano don't provide any headset parts, so far as I am aware, as spares.

The Italians by the way, ain't awkward, there are, and always have been, a variety of standards in the cycle industry which have come about as cycles were developed a long time before we all got globalised ... in fact the Italian standard for this was still widely used, even on some A-Head systems, until we all decided suddenly (or rather, the industry in which I have earned my keep for the last 25+ years decided ...) that we needed 1 1/8" steerers and that bred a whole new bunch of standards!

It's a cartridge headset so in theory the Crown race is less important (?) I'll think I'll get Mosquito to fit it.

From what I can see from the Photos above, the metal rim in your original picture is the crown race.
In the second photo you appear to be trying to fit the head race where the crown race should be.
Fit the DA crown race on the steerer tube first

That's the problem - the lower cap of the DA headset won't go over the ridge.

you absolutely need the crown race

just take it to a shop, it's a relatively quick job - i know cavendish have a crown race cutter tool