CX Head Tube Length - do I add 1-2 cms?

Especially for light weight issues concerning cyclocross / touring bikes & parts.

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by Frans ... -disc.html

Ok, if I shop by desired TT I need the 55cm (Large) but the HT is only 12.5cms. Obviously CX forks are longer but the BB is also higher than a road frame. If the BB is higher, then 12.5cm HT is really tiny for me (I need 16-17cms b/c I have 16 for my road bike.

What's a road fork - 368mm iirc? Do split the difference and assume the top of the HT will be about the same place as a road frame with a 15/16cm HT?

Unf. Focus provide no stack or even stand-over measurements. Given my limited technical skills I'm certain I do not want a front end lower than my road bike.

I'm not wed to Focus so can easily look elsewhere, but I guess I'm looking for a good HT translation rule of thumb.

thanks in advance!

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by simon

from all the geometries i've seen in the last years, focus have the shortest head tubes. compared to their road frames they even make them shorter for the same top tube length.
normally you have a bit more stuff under your stem(conical top cap with brake cable holder or spacer with this function), but that still does not explain the shortness. even more because nowadays you tend to run brake cable holders that are attached to the fork crown or mini v brakes to avoid brake chatter.
maybe you can work with 0° stems(relative to the fork steerer, not to the ground)instead of common 6° to move that handlebar a bit higher. don't run a lot of spacers under your stem, that kills all the stiffness and you won't go through corners the way you want anymore.

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by Irish

Not all modern cx frames have higher b/bkts. Forks are about 3cm longer (400mm dropout to crown) so buy one with a 2 -3 cm shorter h/tube (unless your going to raise your bars relative to your normal position.

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by Frans

Thanks guy, yes I defo I want to raise the front end by 1cm at least. Will bin Focus and their short geometry, cheers.

Giant's geo is quite high, but their frames seem more commuter than racer to me.

Choices choices.

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