Since there isn't a thread on Rockshox's new RS1, I figured I'd go ahead and start one.


Not much solid information yet, but the current rumors say it is supposed to be a new top of the line XC fork a step above the SID.



Not sure what size wheel that is, but it looks like mud clearance won't ever be an issue with it!

If you zoom into the picture you can see a small rectangle on both sides of the fork crown. The current rumor floating around is that it will have some sort of electric lockout (Rockshox's answer to the Magura Elect?), so possibly a charging port? Or more likely, that is how you access the nuts to take apart the fork. There's also the possibility that the whole crown/steerer/lowers (or, I guess they're called uppers now) could be a one piece carbon fiber setup, which would definitely make it light, probably lighter than a sid by quite a bit.

Anyways, what do you guys think?

My question is: if this fork is made for MTB racing, how are people running this fork going to combat getting the stanchions dirty? I know on the lefty forks there's normally a piece that goes over to combat this but I don't see anything on the new RS-1.

Dirt on the stanchions is not a concern for the regular upright (non-inverted) forks, why would it be for this one? If they do make the uppers carbon, this could be a seriously light fork. If it is available in 120mm and came in at or below 1,350g, I would seriously reconsider going Lefty on my ASR5 Carbon.

Looks like a poorly designed Lefty

Ok, but seriously, unprotected stanchions on an USD fork is not smart. The amount of rocks, mud and other muck that gets thrown up at the lower portion of a fork is not ideal for a fork requiring unmarked stanchions to stay sealed and smooth.

How do you combat the legs twisting like noodles? Yet Another hub standard by the looks of it.

The pics on a 120mm bike with Hans Dampf's also point to a little more "Enduro" than XC race. If so, I'd guess it would be because the necessary weight to keep everything stiff bumps up the weight over a SID but is more acceptable to the trail crowd.

On a superlight hardtail frame it would look awesome. On a full susser.... it doesn't look aesthetically great.

Despite my cynacism, I am really looking forward to finding out the finer details.

I wonder if revolutionising the MTB fork market will be as successful for SRAM as revolutionising the road brake market

This is twice the fork the lefty is

But being serious, hub is 15mm thru-axel and those rectangular ports are for a lockout of some sort (Pinkbike did an article). Stiffness is the only reason inverted forks haven't taken over the suspension world as of yet, However for XC you don't exactly need the stiffest fork ever. DVO who is makes an inverted DH fork uses carbon shields mounted to bottom of the stanchions to protect them from debris.

Side note, I really hope they don't start specing stumpies with SRAM wheels

Looks like a metal "Upper", judging from the first pic, rather than one piece carbon.

In the second pic, the bike looks like a Camber, judging from the forward shock mount and concentric FSR "rocker" link, which has 110mm rear travel and is 29er only. The SRAM Roam wheels are also AM level, so the front tire is a fit. Could be a 120mm fork. I also see yet another Avid rotor redesign.

Not too worried about rocks and dirt hitting the stanchions. I think they're safer there, than next to the tread. Might be a bit more susceptible to brush that is whipping back after the front wheel hitting it, but that's all I can think of that would really doing more harm to it than if it weren't inverted.

Paul Turner and X-Fusion have an inverted fork, but it's marketed as a limited edition made in USA AM fork, with lifetime service. They say the trick to improving torsional stiffness is using keyways in the slider, that way they can use round sliders and round seals/dust wipers and bushings.

Front hubs can go wider, and I wonder why they don't. It may be a new hub standard, but I bet they can make it backwards compatible, perhaps with a couple 5mm spacers on each end, if it's a 110mm spacing.

This idea makes so much sense to me. I have wondered for years why the MTB world never adopted the male slider design that almost all higher end motorcycles have used for years.

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For certain parts stiffer is more important than lighter.

The chances of crud on the sliders is less down in the middle of the tire as opposed to slightly above when stuff is flung. Also, as used for years on road motorcycles and dirt bikes, debris tends to be pushed down and out by the fork as opposed to having the hole inthe top where it just keeps getting worked into the wipers. I think this design will be lighter and stiffer because more of the overall material can be carbon in this type of design.

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For certain parts stiffer is more important than lighter.

It has been done a lot before but was always too expensive for both the manufacturer and customer and too heavy compared to "right way up" forks. Even the latest DVO and X-Fusion examples have had production issues, constant delays getting to market and are in strictly limited number for very little profit to the manufacturers. It just hasn't made sense compared to conventional fork design if making money is the order of the day.... which makes it even more interesting to see how SRAM/ Rockshox are getting around the traditional USD challenges. I'll still maintain the Lefty is a perfect design in an engineering sense

It will be interesting to see what the insides of the fork look like. I wonder if it will be pretty standard or maybe some kind of flat/keyed/bearing arrangement to help prevent rotation, or even something non round ala German:A



What would make you think that? To me the crown shape is very similar to heaps of carbon rigid forks. I'm sure RS would have no issues molding it seeing as the one piece crown/steerer on a SID would be in many ways just as challenging to manufacture.

Lefty's don't have the boot around the stanchion anymore either. They only did before because the stanchion wasn't round and it's hard to have a good seal. Now that the exposed portion of the lefty is round, they have a good wiper seal to keep all the contaminants out just like any other non-inverted fork.

Saw one of these up-close this weekend in Fruita, took a couple cell-phone photos (does WW no longer let you upload photos - forced to use a hosting site instead?). It looks nice in person, really beefy uppers. Seems to use a regular hydraulic lockout, the line for which enters in the top of the left leg. I share the concerns about protection for the lowers - not about contaminants, but about damage to the stanchions. On the lefty the leg is closer to the center-line of the bike... plus you have a 50% lower chance of hitting it on something... plus it has a guard. Seems like damage waiting to happen on this fork as it is.

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Enjoying my Funk

Hard to tell from the photos, but the hub just said XO on it... didn't seem like a prototype or anything, just a regular 15mm thru axle. Axle might be different (eg longer) of course.

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Enjoying my Funk

In first picture the tire seems to make contact with the arch ?!

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MSC Koncept Carbon Di2 - 6955g
Leichtkraft Team Carbon - 6868g.

That is his bike rack, there is no arch.

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For certain parts stiffer is more important than lighter.