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Converting short travel MTB to rigid fork

Jun 8, 2023
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Hi All,

New to this forum and looking for some advice. I'm a mountain biker, looking to start some longer 7-10 day euro tours. Was close to dropping 2k on a gravel bike with all the necessary mounting point for panniers etc but having second thoughts as I already have access to a hardtail 100mm travel fork Scott 925 2020 which I use for bombing around roads and greenways etc. I'm now thinking to simply convert this to a rigid fork, and perhaps some alternative handlebar configuration or at least bar ends for long day comfort, and some skinnier tyres.

My question is: could I replace the suspension fork with a suitable rigid fork that would accommodate the 29' wheels, disc brakes and potentially have mounting bolts for panniers or at least bottle cages etc?
Does anyone know of a suitable (budget) fork for this?

Geo of the Scott 925 is here (size M):

Any suggestions are much appreciated!
 
It does work, if you can find suitable rigid forks at an acceptable price.

"Suitable" means with similar axle-crown length and offset/rake to that of the suspension fork, where axle-crown is the weighted length, allowing for sag with a rider on board.
Such forks are longer than regular rigid forks, and are often referred to as "suspension corrected".
Example: https://www.pipedreamcycles.com/shop/crmo-forks/

The back of my envelope converts the head angle and trail quoted in the Scott 925 geometry table into a rake/offset of 51 mm.
offset = (((BB Ht + BB drop) / tan(head angle)) - trail) * sin(head angle)

This ignores any suspension sag as you get on the bike, which will drop the front end of the bike a bit, increasing the head angle and reducing the trail a little over the static values I guess the geometry chart shows. It may be that the 47 mm offset that seems to be normal for suspension corrected forks gives a similar trail with the steeper post-sag head angle to the 51 mm I calculated above.

If you use forks with a different offset or length, the bike handling will change. Maybe you'll get used to it over a few days, maybe you won't.
 
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Jun 8, 2023
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It does work, if you can find suitable rigid forks at an acceptable price.

"Suitable" means with similar axle-crown length and offset/rake to that of the suspension fork, where axle-crown is the weighted length, allowing for sag with a rider on board.
Such forks are longer than regular rigid forks, and are often referred to as "suspension corrected".
Example: https://www.pipedreamcycles.com/shop/crmo-forks/

The back of my envelope converts the head angle and trail quoted in the Scott 925 geometry table into a rake/offset of 51 mm.
offset = (((BB Ht + BB drop) / tan(head angle)) - trail) * sin(head angle)

This ignores any suspension sag as you get on the bike, which will drop the front end of the bike a bit, increasing the head angle and reducing the trail a little over the static values I guess the geometry chart shows. It may be that the 47 mm offset that seems to be normal for suspension corrected forks gives a similar trail with the steeper post-sag head angle to the 51 mm I calculated above.

If you use forks with a different offset or length, the bike handling will change. Maybe you'll get used to it over a few days, maybe you won't.
Hi Andrew!
Wow, that's exactly what I was hoping for, thank you. I've checked the link but I'll have to check that they are compatible with the head-tube and axle size of my scott, I think they are. I'm not worried if the geometry changes ever so slightly, I'll adapt quickly I'm sure. I've searched plenty of sites with no joy so this is very promising. You seem to know your stuff!
Thanks again, very much appreciate your help.
 
Oct 27, 2023
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"Suitable" means with similar axle-crown length and offset/rake to that of the suspension fork, where axle-crown is the weighted length, allowing for sag with a rider on board.
Such forks are longer than regular rigid forks, and are often referred to as "suspension corrected".
Example: https://dev-snowysteps.pantheonsite.io/

The back of my envelope converts the head angle and trail quoted in the Scott 925 geometry table into a rake/offset of 51 mm.
offset = (((BB Ht + BB drop) / tan(head angle)) - trail) * sin(head angle)

This ignores any suspension sag as you get on the bike, which will drop the front end of the bike a bit, increasing the head angle and reducing the trail a little over the static values I guess the geometry chart shows. It may be that the 47 mm offset that seems to be normal for suspension corrected forks gives a similar trail with the steeper post-sag head angle to the 51 mm I calculated above.

If you use forks with a different offset or length, the bike handling will change. Maybe you'll get used to it over a few days, maybe you won't.