The guys over at American Classic have been working hard and following developments in wheel tech closely, they’ve also been quick to move with the demand for wide XC rims. They began with a successful Wide Lightning set that saw 29.3mm internal diameters and they’ve really thrown the cat among the pigeons with the 40mm internal width Smokin’ Guns.
I took delivery of the new hoops from South African distributor Cape Cycle Systems and was blown away at the size of these wheels. 40mm doesn’t sound like very much, but when the previous ten years of mtb rims were practically half the size, you begin to feel like these cant possibly hold the same tire. Since we are not using very wide tires (not double the size for XC) why then have rims grown so much?
I began my foray into the wider is better XC rim just more than a year ago and using light weight XC tires with no sidewall protection they have worked incredibly well. The wide rim doesn’t change the treaded area of the tire, well not very much – they do flatten a little, but the main positive is the sidewalls sit squarely in the bead hook. The sidewall is basically flat and has no “purchase area” for sharp rocks and objects jutting out at your wheels to cut into. They smooth out this vulnerable portion of the tire and make it better shaped to deflect rocks away.
The volume changes; The chamber of air that is contained by the same tire with a wide rim when compared to a traditional rim is bigger. The volume gives you comfort as the tire has more air spring to cope with bumps and rocks while it deflects and conforms to terrain… and its goooood! Just the same as 25c tires have taken the road cycling fraternity by storm with lower rolling resistance, so are wide rims adding volume, dropping pressures required and lowering rolling resistance while they’re at it.
With lower pressure, the tire deforms to the trail and creates better grip in the corners, traction while climbing on loose terrain and incredible stability over sand.
I call it “Plush Sized” – The wide rims are plush in feel and give so many benefits, I prefer the thinner sidewalled and cheaper tires on these as they offer more feedback from the trail and deflect better than their sidewall protected counterparts where the extra rubber on the sidewalls adds firmness that dissipates that feel.
So how do the Smokin’ Guns work…
The AmClassic disk hubs need no introduction and feature on all of their MTB sets, they’re laced three cross front and rear for stiffness, the rim adds so much more stiffness to the whole package but comes at a slight weight penalty due to all the extra material used, yet at 1786g a pair for the 29″ XC wheelset tested is still impressively light.
The rims are huge, they feel massive to work with, but the Vittoria Mezcal 2.25 tires I used to test with initially slipped on with ease and settled into the center of the rim, I added sealant, popped on the bead and sprayed the sides with a soapy solution to let them slip into place evenly. The tires seated perfectly and without fuss. The 2.25 tire was transformed into a girth never seen before. Bill Shook, AmClassic’s President and engineer, said these would be good for 2.25 tires. Now to see for myself.
Everything I knew about 28mm internal rims was true, but this was better this was more! Plush Sized is my play on words. They’re not Plus Sized like the 29+ tire and rim combo that requires a specific bike and fork and wheel to use 3.0 tires and have all the benefits listed above, but they’re plush and they don’t require changing your bike, or fork or favorite tire!
I rode a mix of climbs, grass, gravel jeeptrack, rooted pine forest, pine needles, sand, small rivers (which I wondered if I could float across) and tarmac.
My initial test was on tar heading into the greenbelt and I weaved from side to side feeling out the tires for any lag in steering, I wanted to find out if the extra width of the rim had forced a change in the upper tread profile of the tire and I was very pleased to note that it hadn’t. The steering was quick and because of the immense stiffness of this wheelset, the reaction was immediate. The rear drove, I floated, the front turned, the bike followed. Everywhere I went they just stuck. I rode a section of trail that is a tough test with light needles as a top layer over hardpack and sections of roots that can kick you off line, force you to slow down or ride around them. On these wheels I simply crushed a straight line through them and hit the turn where I wanted. The singletrack ended way too soon.
Previous race lines have shifted, the very wide rims have changed the game and bridged the gap between 29″ and 29+
I have also learned (by smashing a few test rims) so you do not have to follow my learning curve, that while wide rims allow you to run much lower tire pressures in comparison to regular rims, the benefits are not all found there. I have dropped my pressures only slightly from 1.6 bar to 1.3 bar, after having experimented all the way to and below 1.0 bar and while they wont burp and traction is good, the steering slows and the tires wallow. It would be best to run just less than your normal race pressure on a 21-22mm rim. This keeps the tire at a firmness as designed by the manufacturer, and saves the sidewalls and most importantly – You do not smash your rims!
If you’re looking for something to change your bikes capability while remaining affordable then look no further. The Smokin’ Guns will give your current bike a feel you never thought possible. Climb that technical section you could never quite pedal through, float over sand and go faster in more comfort than ever before. Plush Sized has Arrived.
DISCIPLINE MTB Cross Country | Enduro Racing | Plus +
RIMS MTB Smokin’ Gun Tubeless 43mm External Width | 40mm Internal Width Aluminum Disc Rims 29”
SPOKES AC 14/15 gauge Spokes Black | AC Aluminum Spoke Nipples Silver | 32h 3-Cross Front and Rear
WEIGHT FRONT 830g | REAR 956g | PAIR 1786g
HUBS/SPACING FRONT Disc 130 100mm | 15mm Thru Axle Disc 100mm | 9mm Thru Axle Disc 100mm REAR Disc 225 135mm | 10mm x 135mm Thru Axle Disc | 12mm x 142mm Thru Axle Disc REAR SPLINE Shimano/SRAM 9/10/11 or Sram XD
BRAKE INTERFACE 6 Bolt International Standard
LOOK/COLOR AC Black Rims with Gray Hubs
INCLUDED AC Tubeless Tape Installed | AC Tubeless Valves
QUICK RELEASE Cromoly QR’s
UPGRADES Ceramic Bearings | Wheel Bag
*Can be ridden with regular tire and tube