Pipedream Skookum 29er Titanium frame - first ride £2699
8th Jun 2013 | 07:00
Singlespeed titanium hardtail with belt drive
BikeRadar rating:
The belt-driven Skookum proves that chain-driven transmissions aren’t the only game in town
We’d known for a little while that hardtail specialists Pipedream Cycles had one of their Skookum 29er Titaniums lined up for us. So we weren’t surprised when an email arrived asking us what spec we’d like. “We assume you don’t want the belt-driven singlespeed build?” said the email. Belt drive? Yes please, actually. We’ll take one of those.
No, we’ve not taken leave of our senses. Belt-driven bikes have been around for a few years, attracting a very small following, but a following nevertheless. Last year’s epic Great Divide Race winner, for example, rode the spine of the United States on a belt-driven bike.
It’s not a new technology. It uses the same tried and tested manufacturing techniques that your car’s cam belt relies on. In the bike world, though, it’s a brave riposte to the dominant and well-established chain-driven transmission – which is itself hardly high-tech.
Would it work? Would we miss the ritual of chain cleaning? More importantly, would everyone laugh at us?
Ride & handling: So quiet and smooth you forget it’s a belt drive
Transmission aside, the Skookum 29er Titanium acquits itself well on the trail. The large diameter, plain-gauge tubes deliver plenty of rigidity for getting the power down, but you can still feel the benefit of titanium’s comfortable ride quality.
Handling is rapid for a big-wheeler, thanks to a steep head angle of 71 degrees, and it can want to tuck its wheel under if you push the front too hard and lose grip. It feels more XC than this rather burly build suggests.
It’s not cheap, but a belt-driven Skookum Ti certainly has its appeal. Light, fun and low on maintenance, it’s bound to attract attention. Throw in a geared hub and it could, just possibly, be the ultimate go-anywhere bike. And you’d never need to buy a bottle of chain lube again...
Frame & equipment: Titanium with lots of kit options
The Skookum is essentially the same as the well-established, 26in-wheeled Pipedream Sirius trail hardtail, but with those big ol’ 29er hoops and tweaked geometry. Oh, and a shorter fork – it’s designed to play nice with 80-100mm of travel, as the big wheels can help make up the difference in easier rolling over obstacles, anyway.
While we’re on the subject of forks, the X-Fusion supplied with our test bike makes a pleasant change from Fox/RockShox ubiquity, though it’s not without its flaws. The thru-axle quick release on our sample sat at an awkward, forward-facing angle when fully tightened.
The fork also has to hit rocks and roots reasonably hard and fast to work, and at lower speeds it’s a bit constipated. Big wheels and the comfort of titanium tubes take the edge off, but it’s a bit off the pace. While we’re grumbling, the front hub on our test bike had stupid dust caps that fell off every time we took the wheel out, and were a faff to keep in place as you refitted it.
Back to the frame. Chains can easily be split to thread around a bike’s chainstay, but you can’t split a belt. Instead, you need a gap in the frame to allow the belt to be fitted, which of course brings design challenges.
The steel version of the Skookum has a coupling in the dropout where it meets the seatstay, but it’s not quite so straightforward with the titanium frame, which instead features a threaded coupling – a bit like on a climber’s caribiner – partway up the driveside seatstay.
Threaded coupling on the seatstay allows belt fitting
The frame comes with a tool to fit it, and once it’s unscrewed it’s easy to spring the frame apart enough to pop the belt in or out. It’s a one-person job and, although it’s counter-intuitive to ‘break’ a frame in this way, it’s perfectly safe. You won’t notice the coupling in use.
You can spec the Skookum with a variety of options, including eccentric bottom bracket (Pipedream recommend the slotted dropouts as a better chain tensioning solution) and cable routing for a geared Shimano or Rohloff hub.
You can have a standard transmission – with chain – too. Our test bike’s 44mm head tube, belt coupling and sliding dropouts pushed the frame price from £989 to £1,175.
The actual belt comes from bicycle belt drive specialists Gates Carbon Drive. The company claim less maintenance and greater cleanliness over chain-drives, plus a smoother ride, more than twice the lifespan and lower weight; claimed weight for a typical belt is under 100g, against more than 200g for a chain.
Early belt drives used guides at the outer edges of sprocket and chainring to keep the belt in place, but the problem with edge guides is that they’re prone to mud build-up. The Pipedream uses the newer CenterTrack system, with – you guessed it – a raised central ridge on sprocket and chainring that mates with a slot running the length of the belt.
Trail conditions during our time with the Skookum remained stubbornly dry and mud free, so we’re in no position yet to comment on how well it works through a typical British winter. Or summer.
Gates say that heavy clay is known to cause problems, but claim it’s fine in normal mud. It’s certainly quiet and smooth, though arguably no better than a well-maintained chain setup. The difference is that it doesn’t need lubrication, ever.
A central ridge along the sprocket and chainring guide the belt
On our first ride out we didn’t have the belt tensioned enough and suffered a bit of slippage as a result. No problem – a couple of minutes with a multi-tool and we’d tightened the adjustable horizontal dropouts.
No more belt slippage, though the pawls in the freehub scrabbled and slipped a couple of times on steep climbs. The rear wheel still slots in and out of the vertical drops, though you need to check that it’s properly seated before doing up the quick-release.
This article was originally published in What Mountain Bike magazine, available on Apple Newsstand and Zinio.
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