WTB CZR i30 wheelset review

WTB's carbon CZR i30 wheels are aimed at trail and enduro riders, but are only available in 29in diameter – so if your bike uses a smaller 27.5in rear wheel, you’ll want to look elsewhere.

After initially launching the CZR i30 rims, WTB took its time before offering complete wheelsets with its own Frequency hubs laced into the centre of the 28-hole carbon rims, although 32-hole versions are available as a rim-only option.

WTB claims that during lab testing by a third party, the CZR i30 rims proved to be 10 per cent more impact-resistant than the competition but, should you be unlucky enough to destroy one, WTB says it will replace it for free (providing you’re the original owner and were riding your bike when it happened), which is good to know when spending this sort of money.

Aside from that peace of mind, though, just how do these carbon hoops feel when wrapped in rubber, hammered and put to the test?

WTB CZR i30 wheelset details and specifications

The carbon CZR i30 rims use a hookless design (WTB claims this enables it to use more material to bolster rim strength in such a key area) and offer up a 30mm internal width, which is in line with most rims of this nature and intent. In testing, I’ve generally found tyres ranging from 2.4 to 2.6in widths seem to work best on rims of these proportions.

WTB has offset the spokes by 5mm in a bid to create more even spoke tension, and each of the 28 eyelets has been reinforced with extra material (which explains the bulges you can see around the nipples) to help boost durability further.

Easy-to-source, double-butted J-bend spokes are laced three-cross and tightened into place with brass nipples.

Along with tubeless valves, WTB includes its Solid Strip (a nylon strip designed to help prevent the tubeless tape pushing into spoke holes and tearing), which is then wrapped in the brand's own TCS tubeless tape in a bid to provide an airtight seal.

At the centre of the wheel sits WTB’s Frequency hub. There are options for either a Shimano or SRAM freehub at the point of purchase. The freehub has a six-pawl design (each pawl is paired with a heavy-duty spring, though there are lighter/quieter springs available), where the pawls work in two alternating groups of three to provide a five-degree engagement.

My pair of CZR i30 wheels weighed 2,090g.

WTB CZR i30 wheelset performance

Tyre seating and inflation

Getting tyres fitted and inflated on the CZR i30s proved very straightforward and I had zero problems seating the Michelin Wild Enduro and Michelin Wild AM2 and Force AM2 I tested the wheels with.

That said, over time, when changing tyres, I have nicked the TCS tubeless tape in a few spots where the tyre levers have caught it.

The small tears haven’t damaged the sealing, though, and as a result, I've never suffered pressure loss from the tyres.

Hub engagement

Apply pressure to the pedals and the pick up from the rear hub is rapid enough thanks to the five-degree engagement.

Throughout close to a year’s worth of testing, I never once heard a groan, creak or clang from the freehub, no matter how haphazardly I put the power down.

Ride feel

In terms of feel, the CZR i30 wheels are taut and relatively stiff, but at no point felt uncomfortable. That translates to an accurate, direct feel through the turns, where you can confidently load the bike as you compress into supported corners with everything you’ve got.

Thankfully, they’re not so stiff that they’ll ping you off line as you batter through immovable rocks or skim across awkward root spreads.

When things do get rough, they do a decent job of dulling buzz, and I never struggled with them feeling overly harsh or unforgiving on longer descents.

Aside from the small tears to the rim tape and some superficial scratches to the outer rim, my test wheels are holding up really well after a lengthy test period. Both wheels continue to spin true and I’ve had no need to re-tighten spokes throughout, and there’s no play in the hubs that I can feel.

How does the WTB CZR i30 wheelset compare?

Having swapped from Mavic Deemax Pros (£900 for the pair) to the CZR i30s, the change was instantly noticeable, but maybe not as dramatic as I was expecting.

The CZR i30s are certainly stiffer and, yes, that does mean there’s a little more in the way of feedback through the bike, but it's not enough to make things feel unpleasant. The Mavics seem to reduce vibration more, but don’t feel quite as pinpoint in certain situations.

If I compare them to the carbon ZIPP 3ZERO MOTOs, which I rate as among the best mountain bike wheels, the ZIPPs feel more forgiving and certainly a little more comfortable. They’re a shade lighter, too, but cost a chunk more (going by UK prices).

WTB CZR i30 wheelset bottom line

The WTB CZR i30 wheels offer a punchy, pinpoint ride feel, but do so without feeling harsh when riding really rough terrain.

They’ve held up well over an extended test period, handling not just a lot of miles, but countless soakings with the hose. Even after all of this time, they’re still spinning straight and haven’t needed a spoke-key twiddling to keep them in shape.

While they’re not the lightest or the most comfortable (if we’re comparing them to the best carbon rims out there), they’re still solid performers and pricing is competitive.