RockShox and Fox are now also making some shocks with length in millimetres rather than inches. This standard brings us a step up in performance and more.

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Suspension travel is already measured in metrically, isn’t it?

You’re right, you only need to look at a spec sheet to know that. But this is something different, we’re talking about the shock’s eye-to-eye measurement here.

So they’ve caved in to the EU at last, huh?

Don’t be silly, this is a performance and fitting issue. Fox says it now offers its shocks to best fit the design of the bike, so really it’s for the bike designer to decide whether they want imperial or metric sizing, and if regular eyelets or trunnion mounts will best suit the layout.

It will also make life easier for frame designers as it will iron out some of the oddities in imperial sizings that affect leverage ratios.

Trunnions? Sounds like a cannon now

Fox and RockShox make shocks where the upper mounting hardware now sits in the shock body rather than poking out the top in an eyelet. It saves space.

Is space saving a big deal?

Yes, it can be. RockShox says this one of the reasons it’s developed its two new shocks — the Deluxe and Super Deluxe — to give the suspension internals more room. There’s more room for the bushings to overlap, and so there’s less binding under load, and the seals work better too. More importantly, though, the increased length of shocks in metric sizing allows for better gas compression.

Gas compression? Sounds nasty…

No, it’s how the shock works. More room in the shock means the rate curve can be more consistent between different sizes of the same bike. This means the designers can make a size large feel the same as a size small, despite having a different shock length.

Is imperial dead then?

Like most new standards there will of course be a worry that our current bikes will now become obsolete but the manufacturers have said they will “will remain committed to supporting its imperial shock sizes as long as market demand is relevant.” Let’s just hope their idea of “relevant” is the same as ours!