For the third year in a row Bombtrack bikes are helping make the Singlespeed Cyclocross European Championships (SSCXEC) happen. This time the race will happen late in the season in Berlin, coinciding with the upcoming Berlin Bicycle Week and the Berliner Fahrradschau (BFS or the Berlin Bike Show) in a couple weeks time. Growing each year SSCXEC joins the opening night junkyard cross race of BFS, with more racers registered than ever before. To celebrate the race coming to their home country, Bombtrack decided to build up a custom bike to showcase the unique nature of single speed cross. The custom bike will be exhibited as visitors attend the growing urban and lifestyle show, and when everything wraps up it will get go home with a lucky cyclist. Take a closer look at the one-off build after the jump and see how you might be the one to ride away with it…
While SS CX remains a smaller scene in Europe, it certainly is growing. The diversity of the riders gets well represented in this project bike that pulls in components from around Europe, the US, and a bit of Asia.
As soon as Bombtrack decided to build up the project showbike, it wasn’t long until several companies chimed in to take part. A lot of specialist components add up to an eclectic bike that serves as a good representation of the one-of-a-kind bikes you usually find at the start (and on the podium) of singlespeed cyclocross races.
The bike starts off with Bombtrack’s own Arise frame in a size 51cm, with a custom Berliner Fahrradschau x SSCXEC paint scheme. It adds in the classy Wound Up Composites Gravel X carbon fork with its alloy crown.
Wheels are built up with Fast Forward F4R FCC 32hole carbon clinchers laced to Bombtrack Arise hubs with double-butted Sapim Race spokes and 14mm Hexagonal nipples. Rubber duty is taken care of by Challenge 36mm open tubular Gravel Grinder clinchers.
Cockpit is a mix of a Bombtrack Arise bar, Deda Zero 2 stem and seatpost, and San Marco Aspide saddle. Headset is a Ritchey WCS, brakes are TRP Revox Carbons pulled by Tektro lever, and housing is Jagwire CGX SL in braided gold.
The drivetrain is especially unique with a 38T Osymetric 38t ring on Rotor 3D cranks turning a Dartmoor Core chain on a Surly 15T cog around a Rohloff chain tensioner and through an NC 17 chain guide. No chance of dropping a chain here, we’d guess. Looks like someone at Bombtrack might have lost a race this season after their chain came off.
As for the Singlespeed Cyclocross European Championship event itself, the race will be held on the evening of Friday, March 18 to kick of the Berlin Bike Show’s opening night party. The course is built through the sandy and sketchy junkyard behind the Station Berlin venue and loops inside the hall and across the indoor BMX and jump course before running back up a set if stairs and out of a side emergency exit. Every year we have been at the show it has been an excellent course both to race and spectate, and the races end just after dark on the poorly lit and dodgy track. More info about the race including how to register can be found at: BerlinBicycleWeek.com
And to win the bike, just follow Bombtrack Bicycle Co. @bombtrackbicycleco, Berlin Fahrradschau @fahrradschau, and Berlin Bicycle Week @bicycleweek on Instagram to see how you can post your entry to take the bike home yourself.
Hey guys, thanks for sharing this bike.
Manuel from Bombtrack and me put quite some thoughts into the drivetrain. Bombtrack teamrider Stephan Vis is running a similar setup on his Arise. On most singlespeed bikes the chain tensioner is the weakest part. For my own bikes I would prefer a derailleur over most chain tensioners. Thats why the drivetrain seems to be a little over the top, but we prefer a not-dropped chain. Also we wanted to show the visitors at the Berliner Radschau whats possible when riding a singlespeed setup. We were however positively surprised when we got the Rohloff chain tensioner in our hands, which I have never ridden before. Personal I would probably pass on the NC17 chain guide, but one would have to test it in the field, an option we unfortunately didn’t had. Now after the photoshooting is done, I can’t wait to take this bike out for a spin.
Although we had a very tight schedule on this build, we really enjoyed piecing this little crossbike together, especially with a ton of parts you don’t see to often in the shop.
One last thing, this Arise was build up by the Bike Syndikat. I would be more than happy to answer any questions readers have concerning the build.
Thanks again
Marcellus
Bike Syndikat
Why? Why any chain tensioners other than at the dropout, let alone two extra? Is it (falsely) because of the oval chainring? Still unnecesarry. Even with a non-round chainring the number of teeth doesn’t change and it operates like any other SS. Is it to prevent dropping a chain? Who’s dropped a chain riding SS? The bike may be beautiful but I wouldn’t know because I couldn’t look past that drivetrain monstrosity.
No, that is not entirely right. First of all, the Osymetric chainring is not only oval. Second, even if the number of teeth stays the same, the position of the teeth where the chain leaves the chainring doesn’t. After all, when you turn the crank, you can see the chain tensioner moving and that means the tension of the chain changes. I can fully understand that one finds it unpleasant to the eye though.
If it were a true oval chainring it would not change the chain tension at all
From personal experience with non-round, non-oval chainrings, the tension varies enough (from loose to very tight) that you’d get more even tension with a tensioner.
Ugliest drive train ever winner!
Wouldn’t think the added risk of having to use a tensioner and guide would make the oval ring worth it. The beauty, efficiency, and durability of a SS setup is lost on this convoluted mess.
Not really sure such a complex setup is needed. I’ve run an AbsoluteBlack oval ring on my SS mountain bike with sliding dropouts for the past few months using just a typical Surly rear cog and have yet to drop a chain in hundreds of miles. Set the tension when the oval is pulling the most chain (vertical). There isn’t enough slack in the chain when the tension is at its lowest point to overcome the narrow/wide teeth.
Yes, I am kind of thinking the same. I think it would work without the chain guide, maybe even without the chain tensioner. But we wanted to show what is possible and what opportunities there are even within a single speed drive train setup. After all this is not supposed to be the worlds most cleanest and beautiful bike.
Haha, the drivetrain aestheticians sure are irritated. I like it–looks like a few of my former and current fubar rides.
if you are dropping your chain on a single speed on a dedicated SS bike you are doing something wrong. This bike has slider dropouts. No need for a chain tensioner.
Maybe I’m missing the point but any which way you cut an oval chainring in half, through the centre, will have the same amount of teeth on each half. Meaning that the length of chain will be constant. So, weird as it feels, you shouldn’t need a chain tensioner if you’ve pulled the wheel back correctly in the drop-outs.
You are right, the amount of teeth stays the same, but not the position of the teeth. This is not a Rotor Q-Ring, but an Osymetric chainwheel, which is far more away from the from of a circle than the Rotor chainwheels. Running a Rotor chainwheel without a tensioner doesn’t mean you can run an Osymetric chainwheel without tensioner. But like mentioned above, I can fully understand anybody who misses the clean lines and mechanical simplicity Singlespeed is about.
Hi.
This year course in Berlin will stay the same ?
I’m surprised the oval ring on a single speed setup is so difficult to understand. Perhaps a visual aid will help.
so fresh to see someone putting emphasis on function – they seem not to restrict themselfes within the cage of aesthetics. would love to try that one out… and it actually looks not too bad, bit thats a matter of taste – and for those who care..greetings from the Baltics!
holy i really would love to give it a test-ride d*mn. it seems oval chainrings get trendy again these days, i stumble over them everywhere curently, rotor and oval too… any experience anyone?