Syntace C33i Straight Carbon 29 wheelset review

Will Syntace's carbon all-rounder wheels hold up to the brand's quality reputation?

Syntace C33i wheelset
(Image: © Guy Kesteven)

Bike Perfect Verdict

Next-level build quality and tech make the Syntace wheels a standout, hyper-accurate and responsive all-round MTB wheelset at a fair price. However, there are more forgiving wheelsets with more generous damage coverage


  • +

    Light yet broad rims

  • +

    Excellent tire security

  • +

    Exceptional build quality

  • +

    Reinforced freehub and bearings

  • +

    Huge range of options

  • +

    Single spoke lengths

  • +

    Adjustable bearings

  • +

    Well priced for the quality

  • +

    Triple sealing

  • +

    Torque Cap hubs


  • -

    Rim tape and valves are extra

  • -

    Stiff rather than smooth

  • -

    No lifetime warranty

Why trust BikePerfect Our cycling experts have decades of testing experience. We\'ll always share our unbiased opinions on bikes and gear. Find out more about how we test.

If you count all of the different options, Syntace offers over 80 different MTB wheels. This C33i wheelset fits in the sweet spot of lower weight and higher durability for off-road riders looking for significant accuracy and responsiveness. 

Syntace was one of the first wheel brands to produce extra-wide rims, which fattened up tires for extra stability. Today, its carbon rims are available in 28, 33 and 40mm widths. The hooked edges mean pinch point width is closer to 30mm on the reviewed 33mm rim, but that’s still plenty of support for most 2.3 to 2.6-inch tires. Syntace doesn’t supply its High Flow tubeless valves or rim tape with the wheels, which is disappointing for the price. However, the shallow V profile of the center trough of the rims leads to a very easy and leak-free inflation process with a standard track pump. Once over the edge of the V they securely lock in place. 

Syntace C33i wheelset

The cross-ply carbon weave that can be seen on the outside of the rim is said to limit damage to sidewalls (Image credit: Guy Kesteven)

Syntace has been working with carbon fiber for over 20 years, and these second-generation rims use a variety of different composite weaves, including damage limiting cross-ply in the sidewalls. The rims also have 28 cone-shaped sockets molded into the rim for the 28 Q-Lock spoke nipples. Rim weights start under 450g for the 27.5-inch versions, which is on par with Santa Cruz’s Reserve 30 rims and a bit lighter than ENVE’s AM30. Unfortunately, the rims are not covered by a damage replacement guarantee like the Reserves or ENVEs. Instead, Syntace offers a three-year free replacement and a seven-year 50-per cent off replacement plan on mechanical and material issues. 

The build is completed with custom Sapim straight-pull spokes that plug into Syntace’s sculpted block flange hubs. It has a three-cross spoke pattern for plenty of bracing strength. The same length spoke is used on both sides of the wheels, which makes replacement easy. They only come in 6 bolt rotor standard rather than Centerlock. 

Syntace uses its own high-impact load bearings with a specific grease formulation behind a triple seal system. Even after a hard few months of riding, they spin as silky smooth as they did when new. Should that change, they’re DIY adjustable for any slack that does appear. The immaculately machined freehub has a 40-point twin ratchet system for an acceptable 9-degree maximum lag. The Shimano Microspline version is fractionally quicker on the draw at 8-degrees. The standard freehubs are also protected with a steel insert design, licensed from American Classic. Front hubs are available in 100 and 110mm Boost width, with standard 15mm end caps. The TQ version here has bigger end flanges to match RockShox Torque Cap fork legs.

Having the extra connection to the fork really plays to the natural strengths of the C33i wheels. While an increasing number of brands such as Mavic, Crankbrothers, Zipp and Hunt are creating a deliberately more compliant wheel character, Syntace is unashamedly all about stiffness. That’s obvious both under power and through turns, with a real brightness and precision to the trail feel that you get through the tires. Low overall weight means they accelerate easily once engaged, and they’re physically easy to pick up off the trail when you’re flicking and popping the bike around. 

As long as you stick with a durable set of tires, you won’t get battered by on-trail forces too badly. The rims will slice and ricochet around in rocks and roots like the most mobile sets, but they won’t feel sludgy when aiming for the apex, and they certainly won’t suck the life out of your legs when sprinting. 

They stay stable at lower pressures, and despite flatting a couple of tires on rocky descents, there are no signs of rim damage. There’s been no loss of tension in the wheel build either, and the hubs are still feeling great, too. 


If you want an instantly noticeable precision and agility upgrade for your bike, backed up with silky smooth bearing and fastidious manufacturing quality at a low weight, then Syntace wheels should definitely be on your list. If you’re after a compliant wheel that clings to the trail or a carefree replacement plan, there are other carbon wheels out there that will suit you better. 

Tech Specs: Syntace C33i Straight Carbon 29 wheelset

  • Price: $2028 / £1498 / €1498   
  • Sizes: 26, 27.5, 29 (tested)  
  • Internal Widths: 28mm, 33mm (tested), 40mm
  • Weight: 1700g 
Guy Kesteven

Guy Kesteven has been working on Bike Perfect since its launch in 2019. He started writing and testing for bike mags in 1996. Since then he’s written several million words about several thousand test bikes and a ridiculous amount of riding gear. He’s also penned a handful of bike-related books and he reviews MTBs over on YouTube.

Current rides: Cervelo ZFS-5, Specialized Chisel, custom Nicolai enduro tandem, Landescape/Swallow custom gravel tandem

Height: 180cm

Weight: 69kg