Carbon steerer too small for crown race . . .

[moonlite]

So I find myself with a Chinese-made 'Toseek' all-carbon fork which I thought I might use on a slick-tyred urban runabout -- mainly because its uncut steerer is long enough to fit the 2006 Kula Primo frame I have in mind.

But when I started looking at which headset to use, I found that the crown race slips right down to the bottom to the junction with the crown -- where normally you need to apply some force to fit it. I tried a couple of spare crown races that were lying around and all did the same thing. They're actually loose and rattly when in place.

So I broke out the calipers and measured it -- getting a size of 29.2mm. Compare that to the steerer on a Fox fork which comes up at pretty much exactly 30mm. That's a big difference! It's definitely a 1 1/8 in steerer, so what gives?

Do I need a smaller crown race -- if such things exist? Or can I go ahead and use it, relying on the compression from the top cap to keep everything together?

Or could the crown race just be epoxied in place?

 

[novocaine]

it shouldn't be tight but it should be a friction fit. beer cans are 0.1mm, make a shim.

 

[mdvineng]

I think that maybe be designed for the split crown spacer type of sealed bearing installation rather that the old style loose balls type?

https://www.bikeradar.com/advice/buyers-guides/the-ultimate-guide-to-headsets/

 

[moonlite]

it shouldn't be tight but it should be a friction fit. beer cans are 0.1mm, make a shim.

Hmmm . . . I've had a few in the past that required a good wallop to get properly seated, to be fair. 0.8mm seems a lot to be out by. What does that say about the quality control on the fork overall?

 

[moonlite]

I think that maybe be designed for the split crown spacer type of sealed bearing installation rather that the old style loose balls type?

https://www.bikeradar.com/advice/buyers-guides/the-ultimate-guide-to-headsets/

Good point -- and good link! Thanks for that. I did try a modern sealed bearing version as well -- same problem. It's just so off that I'm going off the whole idea of using this fork.

 

[synchronicity]

Great. I just ordered the exact same fork. It's already on the way.

 

[moonlite]

Great. I just ordered the exact same fork. It's already on the way.

Don't worry -- I haven't given up yet. I'm going to try a few things and will report back here.

 

[synchronicity]

I'm going to glue the bastard in.

 

[moonlite]

I'm going to glue the bastard in.

It'd would be interesting to see if your fork has the same issue -- but this seems like a viable fix to me.

 

[mk one]

Just read two other reviews online, one saying it was too large a steerer and another saying it was not round. A lot of reviews saying the brake mounts do not line up though.

Have you thought of using a shim, like a Pace one?