rigid forks question

[e-rider]

I want to swap my suspension forks for some rigid ones (for several reasons) but what axle to crown length do I need?

I've been on the interweb and it seems like there are many different views.

Most companies seem to agree that a 100mm travel suspension fork should be replaced with a rigid fork of between 440mm to 447mm axle to crowm length

.....and a modern 80mm travel fork should be up to 445mm AtoC

I have old 80mm travel rock shox - surly suggest an AtoC length of 413mm whereas Salsa say 425mm and others say between 430 - 435mm?

How much 'sag' do they allow for?

I'm thinking that around 425mm seems to be the 'mean' from the advice given - should I go for the salsa forks, or will they be too low?

 

[Bodhbh]

I have some Kona P2s I bought to replace the old Manitou Axel Super 80mm forks I had on my Rockhopper 2003. iirc the axle to crown length on the P2s is approx 410-415mm and it is almost exactly the same as the suspension forks measure when off-the-bike (i.e. without 'sag', if i understand the term right as baseline compression on the forks with the weight of rider plus bike).

Hope that's some use. How much difference does a matter of 10mm make if the forks are too long/short in anycase?

 

[e-rider]

yeah 10mm either way won't make a huge difference but if I'm spending £60 I want to get the correct size that's all.

I looked at P2s and the AtoC length is 440mm on the ones currently being sold.