Fork enquiry...?

kez1970

Hi all....

I'm in the middle of my first mtb build. My frame is a Sunn Seasons S2 in size large and is designed to take a suspension fork with 120mm travel. The following link shows the geometry/dimensions: http://www.chainreactioncycles.com/Imag ... s%20S2.pdf

If that link doesn't work, then hopefully this one will, just look for the size chart and click on the appropriate frame: http://www.chainreactioncycles.com/Mode ... elID=58991

My question is this: Would this frame by suitable for straight rigid forks, namely the On-One CroMo 26er MTB Fork as shown by this link: http://www.on-one.co.uk/i/q/FOOOCR26DO/ ... _disc_only

Any advice would be greatly appreciated from such a newbie as myself as I'm getting no joy from On-One or Sunn bikes!!!

Cheers,

Daz...

MTBUK

The on-one rigid as you state... Is specced for a frame, requiring 80mm suspension forks... So it would fit... But your front end might be lower than expected. Have a look at the salsa rigid forks 425mm-450mm would be better axle to crown

cooldad

MTBUK wrote:

The on-one rigid as you state... Is specced for a frame, requiring 80mm suspension forks... So it would fit... But your front end might be lower than expected. Have a look at the salsa rigid forks 425mm-450mm would be better axle to crown

Nope. A 120mm fork will have an axle to crown length of somewhere between 495-500mm, or at least corrected for 120mm.
(The ones in the ad say 440mm)

cooldad

Might help.
http://www.carboncycles.cc/?s=0&t=10&&q=fork_selector&

MTBUK

Then in that case, he'll have a very low front end..... Dragsta stylee

Northwind

Take into account sag- as Cooldad says, a 120mm suspension fork will normally have an a2c of 490-500mm ish, but then you sag that by 25-30%, and take off 30mm or thereabouts to get the normal rideheight.

So, you end up looking at something around the 460mm mark if you want to preserve the geometry.

Though, there's a good argument for going a little shorter, since you're likely to be doing things in a bit more XC manner- the On One one will do this.

Spam time! I've got a 465mm Exotic carbon rigid fork, which I used to use in my Soul. The Soda's got a more XC feel so I'm going to replace it with a 440-ish, want to buy my old one?

Ouija

I used to run hybrid forks with a axle to crown of 470mm (after sag) which puts it close to the 120mm suspension forks of mountain bikes....



but replaced it with a Kinesis Maxlight disc 450MTB from Bike24 in Germany. These are taller than the UK equivalent Kinesis forks, which tend to be 430mm high (why the german ones are longer i have no idea).



They do a better job of keeping the front end of the bike up than the shorter 425 and 440mm forks you see a lot of.



They also have proper mudguard mounts as well, which is a bonus over the Exotic ones.

Failing that, get the 460mm exotic forks instead. The Aluminium ones are quite cheap....

kez1970

WOW...cheers for the rapid replies guys, it's very much appreciated. I was really hoping for an affirmative for the On-One forks as I fancied white forks for this frame plus, I like the aesthetic of these forks...however I guess it'll be best to go for the suspension option as originally intended at much greater expense...the build adventure continues...!

Thank you all once again for your replies...