Hi everyone. I have a frame that i am building up to a rigid. Originally the frame had a 100mm tora fork on it. I have been looking at the On One rigid cro mo rigid fork, which has a length of 440mm axel to crown length. Is this rigid fork long enough to compensate for the 100mm travel fork it will be replacing? The length of the tora fork from axel to crown is 500mm, but thats unladen. Any opinions or advice would be appreciated.

Somewhere on the Surly site, they list the lengths of forks in relation to what amount of suspension fork they are meant to replace. I think 440 is about right, but can't tell you for sure. You could always email On One or the internet retailer you're thinking of buying from... or the LBS you might be ordering through would be able to tell you.

500mm ACD sounds more like a 120mm fork. ACD for 100mm forks is usually around 473mm.

440mm seems a little to short for a frame designed for a 100mm suspension fork.

There are other options for suspension corrected rigid forks, with greater ACD, such as Surly Troll fork (ACD 453 mm).

Your weight, on the handlebars, would sag the preload a little ..
have someone measure the fork length while you are on the bike,

It is possible to put a spacer between the fork crown race seat, and the crown race, itself.

If you put a spacer under the crown race, then the crown race will sit on the 28,6mm nominal diameter area of the fork steerer (instead of the 30mm nominal diameter area at the base of the fork steerer) so you will have play between the fork steerer and the crown race.

Need a proper machined spacer, then all is well , you just don't have a quick and dirty kludge.

Or had a father who machined stuff to close tolerances for decades, to see the difference..

Are such spacers available? I have two bikes I'd like to switch to 1" rigid forks but they aren't worth investing in a new, pricier suspension-corrected fork. It seems like a variety of spacers would be a much more reasonable way to accommodate this market than a variety of rigid forks (of different C-A lengths).

edit: Plus, fenders will fit better using a non-corrected fork with a spacer.