Words: Mike Blewitt                                                                                Photos: Colin Levitch
Stans NoTubes rims and tubeless products quickly became widespread across the mountain bike world over the last decade. The popular Crest, Arch and Flow models have always been the core rims but the range has expanded with wheels and rims to suit more uses, and a move to carbon fiber as well.
Still, the Crest, Arch and Flow are long-standing models that suit cross-country, trail and enduro/all-mountain riding. Each rim has been updated and the latest generation Arch Mk3 rims are an ideal evolution for riders looking for a modern trail bike or hard-hitting cross-country rim going to carbon.
Wide is right – to a point
It really is up for debate as to what the right width for a mountain bike rim is. The new NoTubes Arch Mk3 has a 26mm internal width, and 29.3mm external. This is almost 25% wider than the last model Arch, and NoTubes claim that 2.25”-2.5” tyres are the best fit. Matching rim to tyre width is important as it lets you get the most out of the grip available by having adequate support through your tyre. A skinny tyre on a wide rim will expose the sidewalls to rock cuts and move edge knobs too far in. A really wide tyre on a skinny rim will flop around under load unless the pressure is ridiculous.


Many riders feel that 30mm is the sweet spot for trail rims, and 30mm sure is good if you're consistent with your tyre pressures and general setup. I tested the Arch Mk3 rims with 2.25”, 2.35” and 2.4” Maxxis tyres and each size suited the 26mm internal rim width really well, with no burping even at low pressures. That's in part thanks to NoTubes Bead Socket Technology (BST) which is the shallow internal shape of the rim which really helps the bead of a tyre pop all the way into it's seat on inflation the first time. Every tyre I fitted was easily inflated with a pretty standard floor pump.
One of the features that stands out is how shallow the Arch Mk3 rim is. Standing next to most carbon rims in my shed the NoTubes rims stand almost 10mm shallower. They measure just 16mm tall. This obviously keeps the weight down (to about 450g per 29er rim) but it also assists with compliance. Remembering that a good wheel is stiff in the right places and compliant in others, it means the NoTubes Arch Mk3 rims with the 32 hole build on Shimano Deore XT M8100 hubs has matched lateral stiffness with vertical compliance. The total weight of the wheels came to 1783g with tape and valves.

Everyone always says they like how a wheel matches lateral stiffness and vertical compliance, but what does that mean exactly? Comparing these wheels to a lighter set (1395g) of V-shaped carbon rims on 32 hole hubs, it really was noticeable. The rims shared the same internal width, but the reduced chatter over roots and rocks was greatly appreciated. Both wheels felt similar out of the saddle in terms of stiffness, of course the carbon wheels were noticeably lighter and more sprightly. But in rougher sections the NoTubes rims did have a more muted feel – plus that thought of cracking a carbon rim wasn't in the back of my head. This did lead to a more secure feeling, and the slicker or rougher it was the more it was noticeable.


Down the line
It is almost disappointing to say that with 6 months of riding on these wheels on two bikes, I have very little to report. They were used in a bike park, on shuttle runs, on my everyday bike, on a test bike, for all of Cape to Cape, and just about everything in-between.
Speaking to a couple of wheel builders did give some more insights. Some feel that the finishing quality of a NoTubes rim is not at the same level as something like a DT Swiss rim. That is, from the factory the rim is not as round. Therefore, when building the spoke tension isn't as even as it might be on a perfectly round rim. Another wheel builder disagreed, as their experience was that the NoTubes rims built up easily and had an even spoke tension. As always, it will depend on what your own builder's preferences are!

As for the Shimano Deore XT M8100 hubs, they have continued to roll smoothly for the duration of the test period, and most likely will for some time. All in all these wheels have just got in with their job, and I have no qualms in saying that they will for you as well. They may not be a flash carbon rim but I dare say reliability should be the leading decision point for anyone looking at new wheels. If you're not building the wheels yourself, the cost of labour and new spokes and nipples is quite high if you opt for the wrong rims for your riding, or choose hubs that don't go the distance, and you need to have a new set built up.

The Arch Mk3 is a little burlier and wider than the Crest Mk3 and a little slimmer than the Flow Mk3. Each model is fit for purpose depending on how you ride, and they will make a sound wheel set for this year and years to come when matched with a reliable hub set and quality build.
RRP: Rims from $165
From: jetblackproducts.com
-      Good value, good ride quality
-      Really easy tubeless inflation
-      26”, 27.5” and 29” available
-      Not many