As the season starts to wind down, we’ve squeezed in a lot of good cross racing from our Central European base, and have had the chance to test a few new bikes and several wheel and tire combos. While tubeless setups have made progress in the last year or two for cyclocross, we still haven’t found a setup that can beat the performance and reliability of a good set of tubulars. This year we made the full switch to disc brakes for cyclocross, after converting a couple of steel bikes and only adding in disc bikes in for test. So we had a pretty big need to outfit several bikes with proper cyclocross-ready disc brake tubulars to glue up a range of treads. And 4ZA was able to step up and lend us a set of their new Cirrus Pro T30 Disc carbon wheels to test.
We’ve spent the better part of our cross season railing wet, grassy corners and sliding through muddy turns on these Cirrus Pros. Now with just a few more races remaining in our season on what is forecast to be either snow & ice or heavy mud, it seems like a good chance to take a look back on these all-conditions wheels that have carried us this far…
Tech Details
The Cirrus Pro T30 Disc wheels are built up on straight pull DT Swiss 350 hubs with DT Competition spokes, laced 2 cross with 24 spokes front and rear and with brass nipples. The Centerlock hubs come standard with a 15mm thru-axle front and QR rear (presumably because that is the current configuration of Ridley disc-brake bikes), but are interchangeable to most axle standard with DT’s modular tool-free snap-in end caps. The T30 Disc rim has a unique profile relative to the rim brake version with no braking surface, although both share the same basic 25mm wide x 30mm deep dimensions and blunt-nosed profile.
Retail price for this Cirrus Pro T30 Disc wheelset is 1375€, and even though they aren’t listed on the 4ZA website at this time, they are available through any regular dealer of their partner bike company Ridley. Actual weight for our sample wheelset with quick release axle ends was 721g front/823g rear for a total weight of 1544g. That’s just 40g over the claimed weight we were shown on some pre-season spec sheet and less than 25g heavier than the comparable radially-laced, rim-brake version of the same T30/DT350 line of wheels on 4ZA’s website.
As of a week or so ago, 4ZA had actually sold out of their current stock of these disc brake wheels. But they are actually laced by hand in Belgium by 4ZA’a own wheel builders, so keeping up with demand is sometime tough, but it allows 4ZA to build new batches as needed. We’ve been told to expect them back in stock by the end of this month.
Long Term Thoughts
We actually stumbled upon the 4ZA wheels back at Eurobike when searching for European disc brake tubulars for racing cross. We do our best from our Prague HQ to focus on European companies, and even though we know and cover 4ZA’s parent company Ridley well, we hadn’t seen their disc brake wheels.
The T30 Disc wheels are a little heavier than some of the similar depth carbon and aluminum wheels we currently have on test, but that is something we haven’t really notice from the day they left the scale and had a set of tires glued up. In fact because of their 25mm wider profile and more shallow rim bed, we were able to glue on a set of 33mm Hutchinson Toro tubulars with just a single thin layer of Vittoria’s new Magic Mastik which actually drops about 50g off relative to traditional tubular glues, cutting that deficit a bit already. One tires were on, the blunt overall T30 Disc rim profile has been well-suited for our cross racing.
For the duration of our test we have had the multi-use Toro tubulars glued on, so the 4ZA have seen a lot of racing action. The tires have performed quite well in the damp to wet conditions that have dominated our Central European race testing, so excluding a few excessively muddy courses and a couple of early season dry ones, that is what the wheels have had to deal with as well.
We don’t do a lot of deep sand riding, but a fair bit of mud, which they have cut through with relative ease. One thing that we have noticed racing in sloppy conditions is that the low-gloss finish of the wheels has made them susceptible to getting and staying dirty. The finish isn’t matte by any means, but isn’t so slick the mud slides right off. While that may sound like a cosmetic concern, when riding in deep mud that likely result in more friction of the mud sticking to the rims, and on a course with heavy mud the wheels did seem to anecdotally collect a bit more mud and grass on them over the course of several laps compared to other wheels. That said, the tires that we had glued on weren’t mudders, so it was really only one super muddy section on a single course where we noticed it.
The Cirrus Pro’s use of standard DT Swiss hubs has made them incredibly adaptable and their build from standard, reliable components is probably one of their best selling points. We have swapped out the modular end caps on a few occasions to go back and forth from quick releases to thru-axles, so that whatever bike we were racing at the time could easily end up with the tires needed to suit the course conditions. Because of that, while some other wheels with house-brand hubs have been stuck to one bike, we had a chance to ride the 4ZAs on three cross bikes we have on test, letting us get a good sense for their performance.
And the feeling we’ve gotten is that these are a tough set of wheels with a nice amount of give in them. While a lot of carbon wheels have been built with lightness and stiffness as priorities, we get the feeling that wasn’t the case for 4ZA. The Cirrus Pro wheels have felt equally comfortable on stiff carbon bikes and more flexible steel ones, and seem to smooth the ride over everything from hardpack braking bumps to cobblestones. At the same time, we’ve done our best to ride them through some rough stuff and they have come out the other side as true as when they showed up here and looking as good as new (once we clean the dried mud off them.) Durability for a season should be a given for a set of wheels for riding cross, especially at carbon prices. But that isn’t always a safe bet, as we’ve dented a number of aluminum wheels in the same test period, and one of our testers actually cracked two of his own carbon wheels riding on our roads and trails (not products we were testing.)
I feel pretty good about the Cirrus Pro Disc wheels, and when we need to box them up and send them back to Belgium I’ll be sad to see them go (unlike some of the more fragile wheels we sample). Much like the American Classic Aluminum Tubulars that we tested last year (which were almost the same weight but both more narrow and shallow), these 4ZAs are the kind of all around wheel that we were comfortable riding and racing day in and day out. With a relatively low (for carbon) price and the reliability and flexibility of standard DT components, they would make a great wheelset for anyone looking to train and race on one a set of tubular wheels.
