1" threaded headset help needed

jax13

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i've just recieved a token threaded headset from CRC and i want to confirm it is wrong and i'm not being a complete donut.

the crown race is slightly loose on the steerer, nothing a wrap of insulation tape couldn't sort out, the bottom cup fits the frame perfectly, as it is just slightly tight. at the top, the lock nut is 22.2mm, the threaded section of the top race is 22.2mm but the top cup fits a 1 1/8" threaded fork up it with room to spare and the external diameter of the top headset cups flange (which i'm assuming should sit inside the headtube as per every other headset i've seen) is the same or bigger than the external diameter of the headtube itself.

the bottom cup will actually fit inside the top cup as a squeeze.



it looks to me as though i've got a mis matched headset but is it correct for the top bearing to have no contact on the steerer tube at all and the cup rest on top of the headtube or am i being a bit spesh???

item is here.....
http://www.chainreactioncycles.com/Mode ... elID=38682
 
Looks like you have a JIS headset with a 27.0mm crown race. You probably need a 26.4mm standard race. Had the opposite problem recently.
 
the crown race isn't as much of a problem - my biggest issue is the top cup being a marginally larger diamater than a 1 1/8 threaded ritchey headset i took off a frame last week!!!
 
The Park Tools website has details of the acceptable tolerances. Would give a more detailed answer but I am not near a PC at the present time.
 
The press fit of the top cup and the bottom cup should be the same. If the top cup is larger than the head tube of the bike, you've been sent a set of mismatched parts.

The dimensions of an ISO headset are given on the Chain Reaction page you quoted, and you can see from the picture that the upper and lower cups should have the same press fit diameter.

Send it back.
 
one-eyed_jim":1fwyt1u7 said:
The press fit of the top cup and the bottom cup should be the same. If the top cup is larger than the head tube of the bike, you've been sent a set of mismatched parts.

The dimensions of an ISO headset are given on the Chain Reaction page you quoted, and you can see from the picture that the upper and lower cups should have the same press fit diameter.

Send it back.

yep - the lower cup slides into the upper with the same sort of pressure that it goes into the headtube with.

it just confused me that the threaded bits were both 22.2 and everything fitted, maybe token use the same o/d for the cups and just have different sized flanges.

'twill be sent back in the morning.
 
As always, it helps to measure things to figure out exactly what's going on.

I suspect your upper cup may come from a BMX headset. That has a 32.7mm press fit, but works with a 1" steerer and a 21.1mm quill. If Token make more than one version of the same headset it would make sense that the top cup of a BMX unit would appear to be compatible with the other parts of the ISO model, but not with your head tube.
 
sounds about right, although when i rang crc to see what the crack was they double checked and it should have been for mtb / road frames.
 
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