Zipp has rolled out an all-new range of lightweight carbon mountain bike wheels for XC and light trail riding. There are two wheelsets announced today; the Zipp 1ZERO HiTOP SW, and the 1ZERO HiTOP S, both boasting the same highly compliant rim said to help carry speed through rough terrain, and accelerate quickly out of corners.
The SW and S models share the very same shallow (21.2mm) rim with a 30mm internal width, which has recently become the go-to rim depth for XC racers around the world. The wheelsets differ in their hubset specifications, spokes and nipples. The top-end HiTOP SW is sold with the new Quarq TyreWiz 2.0 (more on that here), and is of course the more expensive option.
Regardless, both are intended for XC racing, light trail riding, hardtail riding or full suspension bikes with up to 130mm of rear wheel travel. And, both are sold with a lifetime warranty. Here’s a brief overview of Zipp’s new carbon cross-country wheels.
Zipp HiTOP Carbon MTB Rim
The Zipp 1ZERO HiTOP carbon rims get an asymmetric profile with a hookless rim bead seat design with a 30mm internal width. The recommended tire size is 2.3″ to 2.5″, though 1.85″ to 2.8″ tires would also be permitted. The external width at the rim edge is 37.7mm, giving that top edge a thicker wall that sort of overhangs the rest of the rim wall in the outboard direction. Zipp says this helps to reduce the chances of a pinch-flat.
The Zipp 1ZERO HiTOP are sold as individual wheels only, with no rim-only option available.
1ZERO HiTOP SW
The 1ZERO HiTOP SW wheels are Zipp’s premium offering. Zipp sell both front and rear wheels with the Quarq TyreWiz 2.0 (worth $150 USD), giving the rider instant access to accurate tire pressure readings. The front will set you back $925 USD (£950), while the rear will cost you $1,025 USD (£1,050).
- Wheels: Zipp 1ZERO HiTOP SW
- Rim Internal Width: 30mm rim
- Rim External Width: 37.7mm
- Spoke Count: 24
- Hubset: ZM2 SL Hub
- Driver Options: XD and Microspline
- Boost only
- Claimed Weight: 1,325 grams
At the heart of the HiTOP SW is the new ZM2 SL hub boasting 66 POEs, with drive engagement coming no later than every 5.45°. It runs the very same drive mechanism seen inside the Zipp ZR1 road hubs. That’s a 33-tooth ratchet ring, driven by one of two sets of spring-backed pawls that are offset in their timing. That effectively doubles the 33 POEs to 66 POEs for faster pick-up. That’s something that should prove to be advantageous in technical climbing scenarios.
The ZM2 SL hubset is center-lock only. Twenty-four spokes of the Sapim CX Ray variety lace it to the rim, terminating at aluminum nipples. The front hub is compatible with both standard 19mm thru-axle end-caps, and 31mm RockShox Torque caps. The Torque Cap comes in two separate pieces to allow compatibility with the CL brake rotor.
1 ZERO HiTOP S
The Zipp 1ZERO HiTOP S Wheels are the more affordable of the two options announced today. A set will put you back $1,350 USD (£1,400); that’s $725 USD (£750) for the rear, and $625 USD (£650) for the front. Zipp do not supply the TyreWiz 2.0 with the HiTOP S as standard. These are sold separately at $120 USD (£130 // 145€) per pair, with an extra $30 USD to be spent on the appropriate length valve stem pack.
- Wheels: Zipp 1ZERO HiTOP S
- Rim Internal Width: 30mm rim
- Rim External Width: 37.7mm
- Spoke Count: 24
- Hubset: ZM 900 Hub
- Driver Options: XD and Microspline
- Boost only
- Claimed Weight: 1,495 grams
The HiTOP S is centered about the 6-Bolt ZM 900 SL Hubset that is slightly slower to pick-up than the ZM2 SL of the HiTOP SW wheel. It runs two sets of two pawls, offset in their timing, interfacing with a 26-tooth drive ring. That effectively delivers 55 POEs, with pick-up coming no later than every 6.54°. Twenty-four Sapim CX Sprint spokes lace the rim to the hub.
Can you run the Zipp 1ZERO HiTOP Wheels on an eMTB?
Zipp says, aye. But, only on lightweight eBikes where the motor’s maximum torque does not exceed 55 Nm. Riders still need to mindful that they don’t exceed the system weight limit for these wheels, which is 286 lbs (130 kg). Speaking of limits, the maximum tire pressure is 50 PSI (3.45 bar).