Industry Nine have updated and upgraded the popular alloy Enduro 305 wheelset for 2021. It maintains its 30.5mm internal rim width but gets shallower with a wider rim bead wall. In the name of what, you ask? Improved radial compliance and reduced pinch flat risk. We have all the tech right here.
Here’s their Remote Otter video submission, offering a quick intro to the new Enduro 305 (and more fresh mountain bike wheels!) from Industry Nine’s Jacob McGahey. Specs and tech details below…
2021 Industry Nine Enduro 305
- Intended Use: Aggressive all-mountain riding
- Size options: 26″, 27.5″ and 29″
- Hole Count: 32
- Internal rim width: 30.5mm
- Tire Width: 2.3″ – 2.8″
- Claimed weight(s): 26″ – 1710g, 27.5″ – 1780g, 29″ – 1850g
The Enduro 305 is Industry Nine’s best selling wheelset of all time. Why, then, go to the trouble of fixing something that isn’t broken? Today, like many manufacturers of enduro mountain bike wheels, Industry Nine are appreciating the benefits of wheels with greater radial compliance. At the expense of losing a little in the way of sharp cornering and rapid acceleration, a bit of compliance makes the ride more forgiving. It allows the wheel to meld to the terrain, so to speak. This results in increased traction over the rough stuff, while also absorbing some of those vibrations that would otherwise be left to the suspension or the rider to deal with. But there is a fine balance to be struck, of course.
Industry Nine think they’ve found that balance in the 2021 EN305. When redesigning this popular wheelset i9 set out to achieve two things. One: Improve radial compliance. 2: Reduce pinch flat risk. So…
How do you make MTB wheels more compliant?
![2021 i9 enduro-wheel-rim-alloy-mtb-all-mountain](https://bikerumor.com/wp-content/uploads/2020/04/2021-industry-nine-en305-enduro-wheel-rim-alloy-mtb-all-mountain.jpg)
Shallower rims. For 2021, the EN305 alloy rim is 18.5mm deep (C), losing 3mm of depth as compared to the previous iteration. Jacob McGahey at i9 says this allows the rim to deflect more radially under impact. As a result, the wheel is said to have an improved ride quality and offer greater traction, sticking to the trail better. Instead of deflecting wildly off rocks and roots, the compliance of the wheel should allow it to keep tracking along the ground a little more. This also means they should feel more comfortable (or less harsh), particularly for smaller, lighter riders.
…and how do you stop pinch flats?
To address the problem of pinch flats, Industry Nine have updated the EN305 with a much thicker bead wall (B). It is now 45% wider than the bead wall of the previous generation. This concept is pretty simple really. The larger surface area of the bead wall means that forces are dissipated over a wider area. In turn, that reduces the force experienced by any single point on the rim during an impact.
Industry Nine say this does two things. Firstly, it makes the rim stronger and stiffer at the bead wall, making it less likely to ding. Secondly, when the tyre gets smashed against the rim, as in a typical pinch flat situation, the wider bead wall dissipates the impact, making the tyre much less likely to split. (They’re doing this with their new UL250 gravel wheels, too)
The EN305 rim internal width (A) remains at 30.5mm. The outer (D) grows by 1.5mm in a bid to improve the wheel’s lateral stiffness. At the base of the rim, asymmetry is built in to allow for improved spoke tension distribution. Industry Nine say this is achieved without detriment to the rim strength.
The 2021 Enduro 305 rims are built up to Industry Nine’s Hydra hubs with 690 points of engagement. Thirty-two straight pull spokes lace the alloy rim to the hub. Check out Tyler’s review of the Hydra here.
Pricing & Availability
The EN305 will be available with either Boost or Super Boost spacing Hydra hubs, in 26″, 27.5″ and 29″ options. Industry Nine offer both XD and HG drivers for the Hydra hub and more recently, Micro Spline too. What’s more, the new rims are e-bike approved. Pricing starts at $1,355, with spoke and hub color customization on top.