Skip to product information
1 of 5

Threshold Cycling

Threshold Cycling | Summit SL42 Carbon Road Wheelset | Industry Nine 1/1 & Sapim CX-Ray

Threshold Cycling | Summit SL42 Carbon Road Wheelset | Industry Nine 1/1 & Sapim CX-Ray

Regular price $1,457.00 USD
Regular price Sale price $1,457.00 USD
Sale Sold out
Shipping calculated at checkout.

Low stock: 1 left

Master Handbuilt in the USA

Individually hand-laced, stress-relieved, and precision-tensioned to <0.2mm tolerance with calibrated tensiometers. Stays true for thousands of miles.

Industry Nine 1/1 & Sapim CX-Ray

Machined in Asheville, NC (90 P.O.E. / 4° engagement) laced to Belgian forged bladed aero spokes for maximum fatigue resistance.

2-Year Builder Warranty & Crash Protection

Direct builder craftsmanship guarantee + subsidized crash replacement program with factory rebuild service.

Pre-Taped with Silca Valves (Free US Shipping)

Ships free & insured. Arrives pre-taped with Silca Ultimate Tubeless Tape + Silca CNC valves pre-installed. Mount tires and ride.

The Unfair Advantage on Climbs

Meet the Summit SL42, a sub-1,350g pure climbing weapon engineered to strip rotational weight, defy gravity, and leave the peloton behind. Handbuilt for the uncompromising cyclist, we bypassed the heavy factory markups to pair the world’s most trusted premium components into one ridiculously fast, lightweight package.

Whether you're hunting local KOMs or surviving all-day mountain epics, the Summit SL42 delivers explosive acceleration and razor-sharp handling without sacrificing everyday durability. We started with a blank-canvas, high-modulus carbon rim optimized for climbing. At 42mm deep, it offers a noticeable aerodynamic advantage on the flats and descents while remaining stable in crosswinds.

  • Modern 25mm Internal / 32mm External Width: Perfectly optimized for modern 28c-32c tires. This wide stance creates a flush, aerodynamic profile while allowing you to drop tire pressures for unmatched grip, vibration damping, and rolling efficiency.
  • Hooked Rim Profile: Maximum versatility and safety. Compatible with both tubeless tires and standard clinchers with inner tubes—with zero hookless tire restrictions or 73 PSI pressure limits.
  • Stealth Gloss Finish: A pristine, no-decals gloss clear coat that drops jaws and wipes clean effortlessly after gritty rides.

The Heart: Industry Nine 1/1 Hubs

Built around the legendary performance heritage of Industry Nine 1/1 Road Hubs. Machined in Asheville, North Carolina, these hubs take a no-nonsense approach to precision, remaining confident and capable of cleaning the A-line while leaving budget for a season of bucket list rides. They feature a robust dual phased-pawl drive mechanism utilizing a six-pawl driver and a 45-tooth drive ring. This accomplishes a blistering 90 points of engagement (4° engagement). The moment you put power to the pedals on a steep pitch, the transfer is instantaneous.

The Muscle: Sapim CX-Ray Spokes & Secure Lock Nipples

Laced with the undisputed king of spokes: the Sapim CX-Ray. Forged from high-tensile steel into an aerodynamic blade, the CX-Ray offers the weight of a titanium spoke with a legendary fatigue life that outlasts standard round spokes by millions of cycles. We anchor them with Sapim Polyax Locking Alloy Nipples to shave every possible gram from the outer edge of the wheel while ensuring your tension stays perfectly true, season after season.

Free, fully insured shipping included.

Official 2-Year Limited Warranty & Crash Protection

Every Summit SL42 wheelset is engineered and assembled for uncompromising reliability. We back every wheelset with a comprehensive two-tier protection policy for the original owner:

  • 2-Year Limited Manufacturer Warranty: Full coverage against defects in materials and craftsmanship for two (2) full years from the date of purchase. Because we build with authentic Industry Nine 1/1 hubs and Sapim spokes, your wheels are backed by genuine manufacturer component coverage and direct US customer support.
  • Subsidized Crash Replacement Support: We know real-world cycling happens. If your rim suffers damage in a crash, race incident, or severe road hazard, we provide an at-cost crash replacement program with discounted factory rebuild service to get you back rolling without paying retail price.

Technical Specifications

Intended Use Road Racing, Steep Climbing, Fast Endurance & Gran Fondo
Rim Material & Profile High-Modulus Superlight Carbon Fiber — Hooked (Crochet) Clincher & Tubeless Ready
Aerodynamic Dimensions 42mm Depth | 25mm Internal Width | 32mm External Width (Optimized for 28c–32c Tires)
Hubs & Engagement Industry Nine 1/1 Road Disc (Machined in Asheville, NC) — 90 POE / 4° Engagement
Spokes & Nipples Sapim CX-Ray Bladed Aero Spokes (24F / 24R) + Sapim Polyax 14G Locking Alloy Nipples
Brake & Axle Standard Centerlock Disc Brake | 12x100mm Front / 12x142mm Rear Thru-Axle | Shimano HG 11/12s
Verified Weight ~1,350g Bare Wheelset (1,394g Verified on Scale with Pre-Installed Silca Tape & CNC Valves)
Rider Weight Limit 250 lbs (113 kg)
Warranty & Protection 2-Year Craftsmanship Warranty + Subsidized Crash Replacement Program
View full details
Threshold Cycling | Summit SL42 Carbon Road Wheelset | Industry Nine 1/1 & Sapim CX-Ray $1,457.00
Threshold Cycling Workshop • Build & Setup Guides

Inside the 1,394g Build & 60-Second Disc Brake Setup

Watch how your Summit SL42 wheelset is hand-laced, tension-balanced, and weighed in our shop—plus our 1-minute post-purchase caliper alignment walkthrough for a dead-silent rotor spin out of the box.

🛠️ Post-Purchase Setup Guide • 1:45 Video

How to Fix Disc Brake Rub on New Wheels (Fast Caliper Alignment)

Hub flange and rotor mount tolerances naturally vary by ±0.2mm to 0.5mm between different wheelsets. Never try to bend your rotor—follow this 4-step flat-mount caliper re-centering method:

  • 0:09 Step 1 — Loosen Caliper Bolts: Use a 4mm hex wrench to loosen both flat-mount caliper bolts ½ turn so the caliper body floats freely.
  • 0:42 Step 2 — Install Wheel & Thru-Axle: Seat your new wheel in the dropouts and tighten your 12mm thru-axle to spec.
  • 1:02 Step 3 — Depress Lever to Self-Center: Squeeze and hold the brake lever firmly (wrap a rubber band or strap around the lever if working solo).
  • 1:15 Step 4 — Alternating Torque (5–6 Nm): Snug the top and bottom bolts gradually back-and-forth before final torquing to 5–6 Nm so the caliper body doesn't twist.
🔨 Inside the Workshop Build • 0:39 Short

Building the 1,394g Summit SL42 | Industry Nine 1/1 + Sapim CX-Ray

Most brands quote bare rim weights and hide the extra 40–60g of tape and valves. Watch our complete hand-build hit the scale at 1,394g total (624g Front / 770g Rear) with Silca tubeless tape and valves installed:

  • 0:00 Industry Nine 1/1 Sound Check: Hear the dual-phased 6-pawl driver & 45-tooth drive ring (90 POE / 4° engagement) machined in Asheville, NC.
  • 0:02 Verified Scale Weigh-In: 624g Front + 770g Rear = 1,394g Total with Silca high-pressure tape and alloy tubeless valves installed.
  • 0:14 Boiled Linseed Oil & 2-Cross Lacing: Lubricates threads during high-tension truing, then polymerizes into a natural lock that won't seize nipples.
  • 0:23 Park Tool TM-1 & Dial Truing (<0.2mm): Spoke-by-spoke tension balancing and dial-indicator truing to under 0.2mm lateral & radial runout.

Frequently Asked Questions

Are the Summit SL42 wheels tubeless ready?

Yes, the Summit SL42 wheels are 100% tubeless ready. Because they feature a Hooked (Crochet) carbon rim profile, you have complete flexibility: you can run a modern tubeless setup with sealant, or run standard clincher tires with traditional or TPU inner tubes. Unlike hookless rims, there are zero restrictive tire brand compatibility lists and no 73 PSI maximum pressure caps.

What tire sizes are recommended for these rims?

The Summit SL42 is aerodynamically optimized for 28mm to 32mm tires. With a 25mm internal width and a wide 32mm external stance, a 28c tire sits flush with the rim wall, satisfying the aerodynamic 'Rule of 105' (external rim width ≥ 105% of mounted tire width) to smooth airflow and improve crosswind stability.

What is the rider weight limit?

The Summit SL42 is rated for a maximum total rider weight limit of 250 lbs (113 kg). Handbuilt with 24-spoke front and rear lacing using high-tensile Sapim CX-Ray bladed spokes and Polyax locking alloy nipples, it delivers exceptional lateral stiffness, reliability, and durability.

What freehub body is included?

This wheelset ships standard with a Shimano HG (11/12-Speed) freehub body, fully compatible with Shimano 10-, 11-, and 12-speed road cassettes.

Does the wheelset come ready for tubeless setup out of the box?

Yes. Every Summit SL42 wheelset arrives with Silca Ultimate Tubeless Tape pre-installed and Silca Ultimate CNC Tubeless Valves included. Simply mount your tubeless tires, add sealant, inflate, and ride.

How fast is the hub engagement on the Industry Nine 1/1 hubs?

Industry Nine 1/1 hubs feature a dual-phased 6-pawl drive mechanism engaging a 45-tooth drive ring, delivering 90 points of engagement (4° engagement). Power transfer is instantaneous the moment you put power down on steep pitches.

What is the warranty and crash replacement policy on the Summit SL42?

Every Summit SL42 wheelset includes an Official 2-Year Limited Warranty covering defects in materials and craftsmanship for the original purchaser. In addition, we provide a Subsidized Crash Replacement Program: if you damage your rim in a crash, race incident, or severe road hazard, we offer discounted replacement rims and professional rebuild service so you are never left stranded without a wheel.

Why does my disc brake rotor rub after installing new wheels, and how do I align it?

Because hub flange and centerlock rotor mount tolerances naturally vary by ±0.2mm to 0.5mm between different wheel brands, installing a new wheelset often requires a quick 60-second flat-mount caliper re-centering. Never try to bend or true your rotor! Simply loosen both 4mm hex caliper mounting bolts half a turn, squeeze and hold the brake lever (or secure it with a rubber band if working solo) to self-center the pads over the rotor, and snug the bolts alternately back-and-forth before torquing to 5–6 Nm. Watch our 1-Minute Disc Brake Alignment Video Guide above or on YouTube.