Sensa are new to the UK, but Dutch riders will know that the company have a history stretching back 20 years. Mail order specialists Merlin Cycles have had a good track record in the past with their own line of bikes – so Sensa have a lot to live up to.
The Catena TNT Special props up the bottom of Sensa's 29er hardtail line, blending a sensible looking collection of parts at a price that won't break the bank. But is it any good?
Ride and handling: Easy rolling big wheeler
The cliché that a bike is greater than the sum of its parts works the other way too – a single component can make or break a bike's performance. The Sensa has a fundamental flaw that seriously undermines its usefulness as a trail bike, and that's its oddly narrow handlebar. At 585mm (23in) it's around 100mm (4in) shorter from one end to the other than most handlebars on the market today. That's an enormous difference.
More importantly, it's a difference that affects every aspect of the Catena's handling. Narrower bars reduce the rider's control at speed, in bumpy trail conditions, on technical climbs... you get the idea. Because there's less leverage, arm and shoulder muscles must work harder to keep the bike pointed where you want it to go. More is more where handlebar width is concerned. Most of the bike industry worked this out years ago, which is why you'll struggle to find a bike with a bar this narrow anywhere in the shops.
It's a shame, because although the Sensa is no class leader, in other respects it's an averagely competent entry-level 29er. It rides lighter than its all-up weight suggests, powering up climbs willingly enough and shrugging off momentum-robbing trail obstacles in exactly the way you'd expect from a big-wheeler. Descents, though, become an exercise in hanging on and letting the fork and large diameter hoops do the heavy lifting.
Sensa Catena TNT Special: powerful climber, less fun on the descents
Frame and equipment: a mixed bag
Most of the frame design trends of the last few years are present and correct in one form or another on the Catena. Hydroformed tubing? Check – the impressively fat down tube and subtly flared top tube make use of the fluid-and-pressure based manufacturing process to reduce weight and increase stiffness. Snaky stays? Yep – although clearance at the top of the seatstays is on the tight side for a fat tyre in muddy conditions.
Curiously, there are threaded eyelets at the top of the seatstays to accept a rack, but none on the (rather neat) dropouts. Also conspicuous by its absence is the current frame must-have – a tapered head tube. It's nothing to lose sleep over, particularly given the acres of aluminium around the Catena's head tube junction. It should be plenty stiff and strong enough as it is. We're more concerned with the seemingly trivial lack of clear tape on the wide down tube's underside, an area prone to chips from stones and rocks flicked up by the front wheel. It's an easy DIY fix though.
Holding the front wheel is a coil-sprung Suntour fork with a relatively conservative 80mm (3.1in) of travel. There's a lockout on top of the right hand leg, though the dial on our sample was so loose we were initially concerned that it could rattle its way to the locked out position in use. It didn't, but it's very easy to inadvertently nudge. We'd rather have adjustable rebound damping, on balance.
Shimano's superb mid-range SLX rear mech heads up the component spec list. Rear mech upgrades are a popular tactic to draw attention away from areas that might have suffered at the bean-counters' hands, but this is an upgrade worth having – the SLX mech is accurate, reliable and durable.
Nine closely spaced ratios at the rear avoid the big jumps that plague 8-speed set-ups, but lack the dinner plate-sized low gear of the (better) 10-speed alternative. On the Sensa you'll be reaching for the granny ring earlier. Shimano's budget hydraulic discs aren't the best we've ridden, either. They improve a bit once they've bedded in, but never quite lose their wooden feel or lack of bite.
Finishing kit is all own-brand stuff. It's mostly fine, though the close, shallow tread of the tyres isn't likely to work well on damp British trails. And the handlebar is bizarrely narrow... it'd be simple enough to switch to a wider bar – and it'd make the Catena a better bike in spite of the brakes' and fork's distinctly average performance. But we just don't think you should have to do that on a machine costing £600.