An aero 1x crankset that didn't exist until we asked for it.

SRAM's X-SYNC Road Direct Mount chainring — the aero-profiled 1x ring developed for time trial and triathlon — has always been a carbon-arm proposition. If you wanted it, you bought Force or RED.

We asked SRAM to build it on Rival arms instead. They did. This is that crankset, and it's ours.

48T aero ring, 165mm and 170mm arms, standard or with an integrated power meter.

Read this before you choose a version

These two options are not the same crankset with a power meter bolted on. They run different spindles, which means different chainlines, different Q-factors, and different frames.

Standard version — DUB Wide, 47.5mm chainline, 150mm Q-factor. This is the XPLR gravel spindle. It's built for frames that specify a 47.5mm chainline and for bikes running wide tires that need the extra clearance. The longer spindle also opens up compatibility with wider 73mm and BB92 bottom bracket shells.

Power meter version — standard DUB, 45mm chainline, 145mm Q-factor. This is the road spindle, for frames that specify a 45mm chainline.

Why this is a custom part

SRAM's catalog pairs the aero X-SYNC Road DM ring with carbon crank arms exclusively. There was no factory configuration that put it on aluminum arms — the combination simply wasn't offered.

This is a special-request SKU built by SRAM for State Bicycle Co. Same ring, same direct-mount interface, same X-SYNC tooth profile the carbon builds get. Aluminum arms underneath.

You won't find this configuration from SRAM, from another retailer, or on any other complete bike. It exists because we asked.

What X-SYNC actually does

Running 1x without a front derailleur means nothing holds the chain onto the ring except the ring itself. X-SYNC is how that works.

The teeth alternate wide and narrow to match the alternating inner and outer plates of the chain, so each link seats into a tooth shaped for it. The teeth are tall and square-edged rather than triangular, which means they engage the chain earlier and hold it through deflection. Rounded chamfers manage a chain thrown off-line by a hard hit, and recesses between teeth clear mud and grit before it packs in.

The result is a single ring that retains the chain without a guide, a clutch workaround, or a front derailleur acting as a fence.

And the aero part

The ring profile was developed for time trial and triathlon use — a cleaner shape through the air at the point on the bike where a rider's legs are already wrecking the airflow. Paired with a 1x setup that deletes the front derailleur entirely, you're pulling hardware out of the dirtiest aerodynamic zone on the frame.

Laser-etched graphics rather than printed, so the finish survives chain slap and cleaning.

Why 1x

1x used to mean giving up range. With a 10-tooth small cog and a modern wide-range cassette, it mostly doesn't anymore.

• Nothing to shift wrong. No front derailleur means no trim, no cross-chain penalty, no dropped chain at the worst moment on a climb.
• Less to maintain, less to break. One fewer derailleur, one fewer battery to charge, one fewer thing to knock out of alignment in a crash or a travel case.
• Cleaner frame — aerodynamically and visually.
• Lighter. The front derailleur, its battery, and the second ring all come off the bike.

The honest trade: a 1x drivetrain has bigger gaps between gears than a 2x with the same total range. If you ride flat terrain at a narrow cadence band and want exactly the right gear every time, 2x still wins. If you ride rolling or mixed terrain, race criteriums or TTs, or just want fewer things to go wrong, 1x is the better tool.

How the power meter works

The strain gauge sits in the spindle rather than the rings, pedals, or arm. That keeps it protected from crash damage and rock strikes.

It measures your left leg and doubles it. This is a single-sided system:

• For training, it works. Structured training runs on consistency, not lab accuracy. The same meter reading the same leg the same way gives you intervals, zones, and progression you can train against.
• It won't show leg imbalance, because it only sees one leg. If you're rehabbing an injury or specifically chasing L/R balance, get a dual-sided system.
• A significant imbalance will offset your total in whichever direction your left leg differs. Still consistent, just shifted. Most riders' imbalance is small enough not to matter for training.

• 400+ hours per battery — a full season for most riders
• User-replaceable AAA lithium. No dock, no cable, no proprietary cell. Lithium, not alkaline — alkaline drops voltage differently and gives unreliable readings.
• IPX7 — submersible to one meter for 30 minutes
• ANT+ and Bluetooth — pairs with any head unit, watch, or app

Crank length — 165 or 170

Shorter cranks have taken over road and TT fitting. A shorter arm opens your hip angle at the top of the stroke, which makes a low, aero position sustainable for longer and takes strain off the front of the hip. It also raises pedal clearance for crits and rough surfaces.

Power loss from going shorter is negligible for almost everyone — riders adjust cadence to compensate within a few rides.

• 165mm — riders under roughly 5'8", anyone chasing a lower front end, anyone with hip impingement or tight hip flexors, and most riders in a TT or tri position
• 170mm — the general-purpose length for most riders 5'8" and up, and the safe pick if you're on 172.5 and unsure

Going shorter raises your effective saddle height. From 172.5 to 170, raise the saddle 2.5mm. From 175 to 165, raise it 10mm. Get that wrong and the cranks will feel worse for reasons that have nothing to do with the cranks.

Bottom brackets

DUB uses one spindle diameter across every frame standard — you match the bottom bracket to your frame shell, not to the crank.

The Wide version needs Wide spacing. The bottom bracket itself is the same, but a Wide setup requires spacers 2.5mm thicker on each side. If you're ordering a bottom bracket alongside this, tell us which version you're buying so we send the right spacer configuration.

Wide spindles are compatible with rear ends up to 142mm. Beyond that, check with your frame manufacturer.

You will need a SRAM Flattop chain

SRAM's 12-speed road drivetrains use Flattop chains, a different design from standard 12-speed chains. A Shimano 12-speed chain will not work. A SRAM Eagle chain will not work. A generic 12-speed chain will not work.

Compatible: SRAM Road Flattop D1, Road Flattop E1, or T-Type.

What you'll still need

• DUB bottom bracket matched to your frame shell — and matched to the correct spacer configuration for your version
• SRAM Flattop chain — Road Flattop D1, E1, or T-Type
• 1x cassette — a 10T small cog and wide range make 1x work here
• AXS rear derailleur. No front derailleur required.
• Power version: one AAA lithium battery, included

Fitment

• Drivetrain: 1x, 12 or 13 speed
• Chainring: 48T, direct mount 8-bolt, 6.5mm offset
• Chain: SRAM Road Flattop D1, Road Flattop E1, or T-Type only
• Front derailleur: None. 1x only — there is no 2x configuration of this crankset.
• Standard version: DUB Wide spindle, 47.5mm chainline, 150mm Q-factor, XPLR
• Power version: DUB spindle, 45mm chainline, 145mm Q-factor, Road

Specifications

• Configuration: 1x
• Crank arm: SRAM Rival, aluminum
• Chainring: SRAM X-SYNC Road Direct Mount, 48T aero (CR-XSNC-DM-D1)
• Chainring material: Aluminum
• Chainring finish: Laser-etched
• Chainring offset: 6.5mm
• Crank arm length: 165mm or 170mm
• Speeds: 12 or 13
• BCD: Direct Mount (DM 8-bolt)

Standard version

• Spindle: DUB Wide
• Chainline: 47.5mm
• Q-factor: 150mm
• Part numbers: 00.6118.732.026 (165mm) & 00.6118.732.027 (170mm)

Power meter version

• Spindle: DUB
• Chainline: 45mm
• Q-factor: 145mm
• Measurement: Spindle-based, left-side, doubled for total
• Battery: AAA lithium, user replaceable, 400+ hours
• Water resistance: IPX7 — 1 meter for 30 minutes
• Transmission: ANT+ and Bluetooth
• Part numbers: 00.6118.752.001 (165mm) & 00.6118.752.002 (170mm)

Installation

Straightforward with the right tools: a DUB bottom bracket tool, a torque wrench, and correct preload adjustment. The spindle preload collar is not optional — set it properly or you'll have drag or play, and both eat bearings.

On the power version, calibrate after installation and again whenever you change the battery or move the crank between bikes. Thirty seconds from your head unit or the AXS app.

Reference documentation is available in SRAM's service hub — Rival crankset and X-SYNC Road DM chainring.

OE product information

Not intended for retail sale. This is original-equipment product supplied for dealer service, warranty replacement, and complete-bike build applications.

OE product is the same component that ships on complete bikes — identical specification, identical performance. What differs is how it's supplied:

• Plain bulk or poly packaging rather than a retail box
• No printed manuals or quick-start guides — all documentation is available free from SRAM's service hub, linked above
• No retail hang tags or display materials
• Small-parts and hardware content may differ from the retail pack
• Components may show minor handling marks from bulk packing

Warranty. SRAM's consumer warranty program does not apply to original-equipment components. Warranty and defect claims on this item are administered by State Bicycle Co. Contact our support team with your order number. Crash damage, wear items, and installation damage are not covered.

Custom configuration produced by SRAM at the request of State Bicycle Co. Original equipment service item supplied in OE packaging for dealer service, warranty replacement, and complete-bike build applications; not a retail-packaged consumer product and not intended for retail sale. SRAM consumer warranty does not apply to original-equipment components — warranty administration on this item is provided by State Bicycle Co. Standard and power meter versions use different spindles and are not interchangeable; verify your frame's specified chainline before ordering. Professional installation recommended. Power measurement is single-sided; total output is calculated from left-side data. SRAM, Rival, AXS, DUB, X-SYNC, XPLR, Flattop, and T-Type are trademarks of SRAM LLC. State Bicycle Co. is not affiliated with or endorsed by SRAM LLC. Specifications subject to change without notice.