Bontrager jumped onto the tubeless road bandwagon last year, and after nine months on its top-end Race X Lite TLR aluminum clincher model, we’re sure glad it happened. Not only are they light and surprisingly rigid but they ride very well and are virtually maintenance free. In fact, we’ve barely even had to add air.
Bontrager’s tubeless road system is based on the nearly identical mountain bike setup the company has successfully used for ages, relying on a molded plastic rim strip to seal the rim and firmly lock the tire bead in place. Though it could be conceived as being a little less elegant than rims with a solid outer wall, there’s no denying that it works – and works well (mostly).
The strips are no trickier to install than standard rim strips, and while the resulting fit with the matching Bontrager RL TLR tires is tight, it’s still doable without levers provided your technique is sound (soapy water is most helpful). More importantly, it’s a cinch to inflate a freshly installed tire with a standard floor pump, and you’re rewarded with a reassuring ‘pop’ when the bead is secure.
Removable valve cores make it easy to inject a bit of sealant, too, and in no time you’re on your way. And, as with any tubeless-compatible road wheel, you can always run standard tubes and tires should you wish.
Tubeless tires seat easily with the rim strip installed – at least when the rim strip is new, that is: James Huang/Future Publishing
Tubeless tires seat easily with the rim strip installed
Once you’re out on the road, the Race X Lite TLRs deliver great performance, with the flat prevention and ride quality benefits of tubeless coming as no-cost bonuses.
The reasonably light weight (1,518g per pair with rim strips and valve stems) and low inertia make them noticeably quick to spin up, and they’re admirably smooth on rough pavement. Plus, thanks to the wide spoke flange spacing, they’re impressively stiff from side to side.
We couldn’t get the rims to rub under a 70kg (154lb) rider, even with tight brake pad spacing – something we couldn’t say with Bontrager’s higher-end Aeolus 3 D3 carbon clinchers.
The shallow-profile aluminum rims can’t match those of the Aeolus 3 wheelset for aerodynamics, but handling is superb, especially in unpredictably windy conditions. Helping things further is the slightly oversized (17mm internal width) footprint, which makes for a very round tire profile that predictably and progressively banks from edge to edge. We eventually upsized to Bontrager’s 25mm-wide tires, too, for even more cornering grip and a still-smoother ride.
Externally located spoke nipples are anchored inside reinforcements that are brazed on to the rim. while we appreciated the easy access for serviceability, the flats are rather short so a four-sided spoke wrench is strongly recommended: James Huang/Future Publishing
Externally located alloy spoke nipples
We’ve also been pretty happy with the details. The alloy nipples are externally located for easy truing, the DT Swiss-made rear star ratchet rear hub internals should last for ages, and the aluminum freehub body is compatible with the latest 11-speed drivetrains. Bontrager’s latest quick-release skewers feature a very palm-friendly lever and smooth-operating internal cam, too, generating heaps of reassuring clamp force with minimal effort.
Gripes are relatively minor. The shallow brake tracks are barely tall enough to fully seat a set of SwissStop GXP II pads (which are absolutely awesome, by the way), the spoke nipple flats are a bit short (we recommend a four-sided wrench), and the easy tubeless tire inflation we noted earlier might not be consistent if you strictly adhere to Bontrager’s instructions.
Bontrager says early-production rim strips can bulge into the underlying spoke holes under typical road pressures, compromising the initial air seal (which we experienced). The later-generation strips we eventually switched to seem tougher but, even so, we had the best luck by first laying down a very thin strip of fiber-reinforced tape.
The problem hasn’t resurfaced and it’s been nothing but smooth sailing since then. If you’re out for a set of high-performance, tubeless-compatible road wheels for everyday training and/or racing and aren’t specifically searching for aerodynamic performance, we can’t recommend Bontrager’s Race X Lite TLR wheels enough.