Rigid Forks HELP

smegurmum

where it says on rigid forks: built in suspension geometry. is it generally accepted that it is to emulate 100mm travel forks, unless otherwise stated?

if so are there any produced to emulate 130mm+ forks?

supersonic

Are a few things to consider. When a fork manufacturer says a 445mm fork will be good for a 100mm suspension fork, it is a rough average estimate. Most 100mm forks are at about 485 crown to axle length, minus sag and a bit more and there you are.

So if you have a 130 sus fork, then on average a 465mm. But as above, have to work it out on what you have and what you want.

Kiblams

Surly do a Chromo fork (Karate Monkey) which has 468mm A-C, its designed for 29" wheels with suspension correction. They are heavy duty forks but are still lighter than the majority of suspension forks below £800.

My bike had only 80mm travel and I replaced it with a surly instigator (450mm A-C) which made the head angle more slack, suits me fine though.

I am sure they will have similar A-C sizes in carbon if that's what you are wanting.

bomberesque

if you're thinking of replacing the forks you have on your bike at the moment with rigid and you're happy with the way your bike handles today, then I'd measure the A2C (with you on the bike and leaning forward a bit, perhaps asking an anble assistant to lend a hand) and try to find a fork of similar length

Otherwise, as SS says; 465-485 A2C unloaded for 100mm forks is about average, 445mm rigid forks are generally sold as being 100mm sus correction, 425 for 80mm and 465mm for 29er or 120mm forks. Non sus corrected forks are (usually) 385-400

Do check the A2C though, I had a Ritchey WCS on order for the Tranny as they said it mimicked an 80mm fork with average sag, but they didn't state the A2C. Ibis said this would be OK and generate a HA of about 71 which is steep, but for the use I'm putting it to sounded OK. I finally found the A2C for the WCS in the maintenance manual for the fork and it is listed as 409 which is really short and too short for the frame (Ibis estimated it would provide a HA of 73 Deg :shock: ) fortunately the fork hadn't shipped so I was able to cancel and swap for something more appropriate without hassle.