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SOC18: Alchemist RR2 adds new angle on hub engagement for 1240g XC carbon wheels

alchemist RR2 carbon fiber XC Marathon mountain bike wheelset with angled ratchet ring hub engagment
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Italian wheel brand Alchemist Bicycles debuted their XC/Marathon RR wheels in 2014 as a mostly symmetric but still unique set of carbon-rimmed mountain bike wheels. Now, the new Alchemist RR2 changes everything, adding separate designs for front and rear hubs, carbon and alloy hub options, and an all-new “Eagle optimized” engagement system.

alchemist RR2 carbon fiber XC Marathon mountain bike wheelset with angled ratchet ring hub engagment

The carbon rims switch to a zig zag spoke placement to increase the cross bracing angle – the left side hub flange sends spokes to the right side of the rim.

alchemist RR2 carbon fiber XC Marathon mountain bike wheelset with angled ratchet ring hub engagment

Before, both rims had a respectable 26mm internal width. Now, the front grows to 28mm inside with a 24mm rim height and drops to 20 spokes. This helps it shed a few grams while improving lateral stiffness and compliance. So, comfortable and stiff.

The rear hub stays at 26mm internal, is only 22mm tall, and gets 24 spokes. Similar goals, but using a thinner rim to gain compliance with more spokes to make sure your pedaling efforts are driven all the way out to the tire without losing power to torsional flex.

alchemist RR2 carbon fiber XC Marathon mountain bike wheelset with angled ratchet ring hub engagment

The rim itself is reworked with a new layup process that wraps the carbon around the bead wall to improve impact resistance and decrease the risk of delamination (by up to 30% compared to their prior RR rim). A “High Toughness Epoxy Resin” further improves impact resistance.

alchemist RR2 carbon fiber XC Marathon mountain bike wheelset with angled ratchet ring hub engagment

At the hub, they’ve increased the diameter of the 36-tooth ratchet ring so that the bearing can fit inside it. Not only does this improve alignment of the moving parts, but the increased diameter helps it hold up to the increased torque created by today’s massive 50-tooth SRAM Eagle cog.

alchemist RR2 carbon fiber XC Marathon mountain bike wheelset with angled ratchet ring hub engagment

The other improvement comes from angling the teeth. Note how these teeth slant outward…

alchemist RR2 carbon fiber XC Marathon mountain bike wheelset with angled ratchet ring hub engagment

…and the spring-backed ring inside the hub shell slant inward. This design forces them to align perfectly as they engage.

alchemist RR2 carbon fiber XC Marathon mountain bike wheelset with angled ratchet ring hub engagment

The new Alchemist RR2 wheels will come with either carbon hubs (1,240g per set, €1,835) or alloy hubs (1,250g per set, €1,739). They’re Boost only and available with XD or Shimano freehub bodies.

alchemist RR2 carbon fiber XC Marathon mountain bike wheelset with angled ratchet ring hub engagment

AlchemistBikes.com

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D-con
D-con
5 years ago

I mean, for a first world (Italian, I believe) made carbon rim with some interesting ideas that price is surprisingly reasonable.

Pavel Dub
Pavel Dub
5 years ago

20/24 CX-Rays(?, hope not) is not enough at mtb, even at road disc. RR is on 24/24 CX-Rays. Wheels should have weight limit ap. 70 kg.

workonsunday
workonsunday
5 years ago

I must have gone blind, is this 650b or 29?

Jim E
Jim E
5 years ago

20 spoke front sounds a bit sketchy.

Drew Diller
5 years ago

So DT Swiss is licensing their patent now? I’m not trying to be a curmudgeon here, just curious! It’s a good design.

Maciej Pike-Biegunski
Maciej Pike-Biegunski
5 years ago

Low spoke count wheels are plenty strong…..until a spoke breaks. Spokes themselves only weigh a few grams each, and on an MTB wheel where aero doesn’t matter there’s no reason not to run 28 (or better yet, 32) spokes each.

A broken spoke on a 32h wheel on a long ride (say Whole Enchilada in Moab) isn’t even enough to back off on getting some air and having a great ride. A broken spoke on a 20h or 24h wheel means that the rim is rubbing the frame or fork and it’s a long walk for you!

While I don’t abide low spoke count wheels, the bearing on a star driver looks excellent. Would this retrofit to a DT hub?

Damien Milazzo
Damien Milazzo
5 years ago

@drew diller – the dt swiss patent is done. Others can now use it freely.

Zoso
Zoso
5 years ago

I dunno. The Mavic wheels I used to run were pretty bomber and they had a very low spoke count. Even if a spoke broke, the rim stayed relatively true. And those were Aluminum. And I’m not talking XC-type use either.

Cru
Cru
5 years ago

I keep reading about the massive torque created by the 50 tooth Eagle cassette, which is nonsense as long as you do not use it with a ridiculously small chainring. For the torque at the rear wheel, only your smallest gear ratio is important, and that did not change much after we had 22×36 options.
@Drew Dillier, as far as I am informed, DT’s patent expired. I expect to see a lot of these designs popping up in the near future.

Johann
Johann
5 years ago

What’s the engagement for the hub?

Brendan
Brendan
5 years ago
Reply to  Johann

360° ÷ 36 teeth = 10° of engagement.

RobertW
RobertW
5 years ago

I won’t ride with less than 28 spokes just because of the danger of sticks in my wheels. The struggle is REAL. Otherwise these wheels look pretty neat.

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