Whether you're a flyweight climber, powerful puncheur, Strava segment shredder or Red Hook racer, you'll spin so much faster on these Fat Boy Rims
I’ve engineered the Koppenberg DM8 Super Fat Boys to be aero, light, stiff, robust, and durable. You know, all that stuff that every high-performance wheel brand lays claim to - some more truthfully, and many more optimistically than others.
But for the DM8 series rim profiles, all of that was simply not enough. After all, I already had my most successful and well established DMX range of wheels chugging along nicely thanks, and the DMX wheels ticked all those boxes loud and clear.
So with DM8 what I wanted was to go way beyond DMX, and at least one stage further than any other maker has yet considered for their premium performance road wheels.
In my view, it’s simply not enough to be just aero, light and stiff. Most of the really top-end, big bucks wheels get this just about right - more or less. But if you want to go really fast out there in the real world, consistently fast and always in supreme comfort and sure-footed safety, your tyres are in fact the key.
More specifically, matching the rim to the tyre width to achieve the optimal performance window of the tyre. So my focus with DM8 was on optimising ride performance with 25mm (and upto 28mm) tyres. Because those are what every roadie and racer rides these days - even if they don’t yet know it!
It’s for this specific reason that the DM8s are so wide. Wider internally in fact than any wheel currently offered by Zipp, Enve, Reynolds, Easton, Mavic, Fulcrum, FFWD, Campagnolo, Shimano, or to my knowledge, any other purveyor of fast wheels.
Sometimes I think that many of these otherwise fine wheels have their gimmicks tagged on by the marketing department - dimples, spoilers, stick-on fairings, extra-loud stickers, sharks tooth inner radii. I have my fun with this part of the game too, so this is not a complaint from me. But the thing that none of these “solutions” address is perhaps the most important of all: the question of optimising the size of tyre everyone is riding these days. And the fact is, on anything skinnier than a DM8 rim, those 25mm tyres cannot attain their optimal shape.
My goal with DM8 was perfect tread profiles with 25mm tyres - tyres that arc smoothly from one edge of the rim to the other, without any need for high pressures nor bulging sidewalls. Because what this means to you, out on your bike is more! More speed, more grip, more comfort, and more safety. And all of this with less effort.
Get more from your wheels!
More Speed. More Grip. More Comfort. More Control. More wheel!
Demand more - spend less! Less cash. Less effort. More wheel!
DM8s are upto 30mm at their widest, yet will fit most modern road, race, track, gravel and CX bikes. You can find out how by clicking the read on link below!
DM8 rims are wider than most rims are deep!
Choose from two build variations for the road, centre lock disc with thru-axles for road/gravel/CX, or fixed/fixed track hubs to go race those Red Hook Crits. Combine with three rim depths and the DM8s range from 1470 grams and £990 / pair.
I make each and every wheel entirely by hand, and customise the build precisely - for you and the way you ride. They’re the best wheels I’ve ever made. And I’m confident that they’re the best wheels you’ll have ridden - ever!
Please read on to find out how DM8 came about, and why these very fast #FatBoys entirely outperform and supersede my previous best-selling DMX range of wheels.
You see, my previous generation rims - the X/DMX series - were engineered specifically to work best with those 23mm tyres that we were all still riding the road just a few years back. As with DM8, this factor was the starting point for the rim design, determining from the very outset the ideal internal and external widths.
The X/DMX wheels rode like the wind on these 23mm tyres, and so they became the fastest wheels I’d made - as well as my fastest selling! The only problem was that soon after, everyone started riding 25mm tyres. Oh, and at the same time, tyre makers started making their 23s truly 25mm across and even bigger.
That’s why I took everything learnt from more than 5 years working and developing the DMX profiles and wheelsets, and put it to work on DM8, back in the second half of 2015.
To my current knowledge, all big-name makers of so-called wide profile road wheels are still coming up with narrower section rims than I’ve developed for DM8. And because of this restriction on the tyre right at its base, which defines how the tread will take up its shape across the rim, all such wheels will only therefore deliver optimal real world performance when paired up with genuine width 23mm tyres.
The problem with tyre sizes
Fit a Schwalbe Pro-One, Conti GP-4000-Sii, or Vittoria Open Corsa Comp in size 23, and what your bike’s really wearing this season are 25mm tyres. That’s right - 25mm wide.
And let’s not forget that many riders are now buying into the latest performance craze and riding tyres with 25 written on their sides - but failing to notice that these often come in around 27-29mm wide for real. It’s way too much tyre - not to mention all that extra rotating weight - for most rims to manage without requiring very high inflation pressures in excess of 100 - 120 psi to stabilise the tread, resulting in sidewall bulge, light bulb effect, whatever you want to call it.
The problem with this bulge is its effect on the tread shape, tending to flatten it off at the upper section, which increases roll resistance, effectively wasting grip where it’s not needed. Think of your bike in the fully upright, power-on position - you’ll realise that in this scenario you don’t need excess amounts of grip, just plenty of contour hugging micro-deformation in the tyre carcass to smooth out the surface and waste the minimum energy in bouncing off the road.
Conversely, those bulging sidewalls round off the tread area’s all important shoulders, delivering a much smaller contact patch where the very broadest contact area is precisely most needed - think of your bike leaning into that high speed corner coming down your favourite alpine col. Or that streaming wet town centre junction in the middle of your training ride.
So what does all this matter?
At the end of the day, the entire purpose of your wheels - in fact, it’s the one and only purpose of your entire bike! - is to connect you to Planet Earth: as fast, as securely, and with as much feedback and fun thrown in as physically possible.
To do this well, it all boils down to how your tyre is served up and delivered to the road, the trail or the boards. Nothing simpler than that. So the shape of the tyre tread, as well as the amount of pressure required to hold it in place, and how these two factors combine to influence tyre performance is something that I’ve spent a great deal of time thinking on and investigating.
And it was with this simple aim of creating the perfect tread profile - smoothly arcing from one edge of the rim to the other, without any requirement for excessive air pressure, nor bulging sidewalls - that the DM8 series was born.
What all of this means to you, out on your bike is more speed, more grip, more comfort, and more safety. And all of this with less effort.
DM8s come in three depths and two build variations. From the ride anytime-any place-anywhere Flyweight 38mm DM838s, through the all-rounder Rouleur 45mm DM845s and the flat-out Speedster 58mm DM858ss.
Each wheel can be built with standard road hubs for rim brakes and QR axles, fixed gear for track and Red Hook racers, or with the latest centre-lock disc brake hubs shown above, for your go-anywhere, gravel, adventure, CX or any other type of bike built with thru axles.
Custom options for road builds include your choice of hub colour from several options and finishes, including these rather fetching, but very limited run in hand polished bare alloy.
Track hubs are fixed/fixed at the rear, and any colour you like so long as it’s black. But it’s entirely your choice to go super stealth with these shot peened matt hubs, or super sexy with the deep gloss version.
On road builds, I can increase your rear wheel’s torsional stiffness by choosing the Supersymmetry R55 rear hub - it adds a few grams over my standard asymmetric R50 hub, but the deep non-drive side flange adds big benefits for heavier and more powerful riders.
DM8s weigh in from 1470g a pair, so these bad boys pull off that magic trick of being super fat without being heavy.
Priced from £990 - £1099 a pair, they won’t leave your wallet entirely empty - unlike many better known, but lesser performing, over-priced wheels you could go and get yourself instead from any of the usual suspect big boy wheel brands.
The DM8 series wheels represent everything I’ve learnt about engineering, making and riding great wheels, so naturally I love ‘em. And I’m convinced you will too.
But who cares what I think? It’s much more fun to take a look at what the riders who’re already spinning their own DM8s have to say by hitting this button above.
Are you ready to Spin On These?
I’m ready and waiting to make you the best wheels you’ve yet to ride - so if you’ve seen enough already…
To wet your appetite for a new life of effortless speed, demon handling and sublime comfort out on your favourite road or trails…
Here’s some of the wheels I made earlier …
Pro triathlete Joel Jameson rides Sarto Lampo and the DM845 Fat Boys
British national multiple road, track, hillclimb, mtb and CX champ Lewis Askey, out for another spin and another win on his custom disc DM845s
Pro triathlete and 9th at the 2016 ITU Long Course world champs, Catherine Jameson races on her DMX960 and DM858 Fat Boys
Double British Elite national TT champion Hayley Simmonds rides her Fat Boys at the 2015 Women’s World Road Race Championships - on her way to putting team mate Lizzie Armistead onto the top step of the World
World Men’s Road Race Champ Maurizio Fondriest and friends
Newly crowned 2016 British Ladies triathlon champ Catherine Jameson on her way to 9th in the 2016 ITU Long Course World Champs
Dutch Junior National team rider Ide Schelling at the 2016 Men's World Road Race Championships finished 7th on these custom DM858 / DMX990 pairing