Genesis iO – 120mm fork ok?

is a 120mm travel fork (manitou black) gonna be ok with this frame? they recommend 80-100 but will 120mm drastically affect the feel of the bike? head angle is about 70 degree with the figid so would a 120mm make it about 69 degree ish? or slacker than that?

anyone know?

They say 100mm is ideal but then my mate had a ‘zocchi MZ and replaced it with a Fox F120 and the axle to crown length was very similar.

Use that measurement instead of travel and you might find a 120mm fork is fine.

(This was on a different bike btw, just saying going by travel alone doens’t give the whole story)

manitou’s are 480 and the rigid forks on the iO are 440. will the extra 40mm make a difference?

When I put 120mm Blacks on my Trek that had 100mm forks recommended the thing I noticed was that on some steep hills front sometimes could lift and made it a bit harder to get to the top. Then got back to 100mm and it was better. But still 120mm when going down was more fun. Soooo maybe look for some U-turn/RTWD forks – best of both worlds.

I run an IO ID (which has the same geometry} with Fox 120’s & it is not quite as quick as when it had 100’s on, but to be honest it has not upset the ride at all, I have also used Manitou 130’s and they were ok as well.

I had a similar question. I emailed them directly and they gave a quick and helpful response

A long Manitou on a 100mm frame: Two wrongs do not make a right. 😆

It’s not about travel, it’s about distance between axle to crown, both static and dynamic, and trail. Key here is your axle-crown measurement.

I’m running an Io with Marzocchi MX Pros at 100mm, which comes up pretty long on axle to crown length compared to 100mm Manipoo or RS forks. For example, a swapped a pair of 80mm MXes for a pair of Rebas at 100mm a while back on another bike and gained 4mm in total axle-crown length.

Measure the axle-crown on your Manipoos and work out the difference. I’d say 40mm is a bit much, but with 25% sag, that drops to 10mm. Handling will be vaguer, as Stormer says above. BEar in mind you won’t always be at 25% sag, either – there will be times when the fork is extended, which will make the handling squirrelly.

Check with Genesis about warranty as well; it’s unlikely to be covered, and the designers may also not have factored in a longer lever (ie fork) into the equation.

I’d also consider a fork that’s not a Manitou. Seriously. Get a second hand Marzocchi or RS from the classifieds. That’s what I did when I built up the Io last year.

Or keep it rigid!

Picked up my 09 iO weds. Tbh for a cheap and cheerful mud bike its a bit sexy! Got it filthy already and feel really guilty… *sigh* I can already see upgrades galore coming and then having to get another cheap bike to ride in the bad mud.