Between all the new wheel, tire, axle, and shock standards in the past five years, you might have missed one of the most important new trends in cycling. That would be the move to wider rims.
Wider rims dramatically alter your tire profile. The wider bracing gives better sidewall support, which allows you to run lower tire pressures, resulting in improved traction and ride quality. That’s the theory, anyway.
In the real world, it doesn’t always play out like that. The problem is that standard tires were designed around the bastard offspring of chopped up road rims. When you pair those tires with modern wide rims, you end up with a square profile that engages too abruptly.
To remedy the issue, Maxxis has developed a new line of Wide Trail (WT) tires. These tires are optimized for rims with an internal width of 30-35mm. That’s great for anyone with a fancy new bike or wheels, but what if you’re on a rim that’s not quite that wide. Maybe you’ve on a 27 or 28mm wide rim, what then? Should you stick with a classic tire or is a WT tire a better option?
To answer that question, Mtbr reached out to Bobby Brown, who runs marketing for Maxxis in the U.S.
Mtbr: Wide Trail tires are built around a 35mm inner rim width, while your regular tires are designed around 21-23mm. At what rim width should you pick one tire size over the other?
Bobby Brown: We recommend moving to a WT tire when you are running 30mm or wider internal width rims for the optimal tire profile. That is the point of diminishing returns on the classic tires and the lower limit of what the WT tires work well on. The older tires work very well over a range of 21-29mm wide rims.
Mtbr: Are there any benefits to running a WT tire on a narrower, sub 30mm rim? Any negatives?
BB: There would not be any benefits running a WT tire on a narrower rim. This will create a rounder tire profile, requiring a greater lean to engage the sideknobs. Conversely, when running a standard tire on a rim much wider than optimal the sideknobs will engage too early, leading to premature tread wear and opening up the possibility of being able to lean the bike past the shoulder knobs.
A primary design consideration with Wide Trail was to define how and when the tire engages knobs. We designed WT to engage certain knobs at a specific lean-angle, to feel as consistent and predictable as our other sized tires when mated with their proper rims. Rim width plays a huge role in the final tire profile and through WT we have been able to maintain a consistent Maxxis cornering feel when riders use wider rims.
Mtbr: What’s the volume/width of your average 2.3 tire on a standard 25mm rim versus a Wide Trail 2.5 on the same rim?
BB: All measurements taken at 30psi, on a 24mm internal rim, a 2.5 WT tire measures 63.4mm at the tread and 59.5mm at the casing whereas a 2.3 tire measures 57.7mm at the tread and 56.8mm at the casing. On the optimal 35mm inner width, the 2.5 WT tire measures 64mm at the tread and 62.7mm at the casing.
An interesting observation with these numbers is the effect of rim width on the tread and casing width. The tread on the Wide Trail tire only grows by a half millimeter whereas the casing width grows by 3.26mm. This shows how much the rim width affects casing shape.
Mtbr: Is there any difference in weight between the standard and WT versions of the same tire?
BB: We do not offer WT as an option, it’s a new size not a tech like EXO/DD. For example, all 27.5×2.5 DHFs are Wide Trail. We want to make sure people are not comparing the weights of a 2.5 to a 2.3 and there really isn’t an apples-to-apples comparison in our lineup.
Mtbr: Your current Wide Trail offerings are in the 2.4, 2.5, and 2.6 range. Why doesn’t Maxxis offer any Wide Trail tires in the more traditional 2.3 size?
BB: There is an ideal ratio of rim width to tire width in order to provide an optimal tire cross-sectional profile. The WT design primarily benefits larger 2.4-2.6 tires when used on wider rims. Narrower 2.3 tires set up with an optimal profile on 21-29mm inner width rims.
Mtbr: There are currently eight different tires available in the WT family. Can you give us any hints as to what other tires or sizes are in development?
BB: Wide Trail DH tires are on the way for 27.5 and 29 wheels in the DHF, DHR II, and Shorty patterns. Beyond that all I can say is that we will be aggressively expanding our 29×2.6 offerings in 2018. The 29×2.6 Rekon will be available this Fall followed by many others early next year.
Have more questions about WT? Visit the Mtbr forum to hear more from Maxxis and other riders.