Something different in hydroformed aluminium from BMC

This is only the second BMC bike we’ve ever had in to test at road.cc – the other was the SLC01 Pro Machine nearly two years ago, and, if the truth be told, we’re pretty excited about getting aboard the Streetracer SR01 and finding out what kind of ride the Swiss technology has to offer. In many respects the SR01 is a similar design to that SLC 01 made from aluminium rather than carbon.

At £1599.99 the SR01 counts as a high end aluminium bikes these days, and it justifies the tag being built around one busy alloy frame. There’s a lot going on here. Check out the seat tube cluster, for example. Essentially, the top tube splits a few inches before reaching the seat tube, the upper section continuing on in a straight line, the lower section curving downwards to connect right opposite the seatstay junction.

This produces a frame shape that’s vaguely similar to GT’s Triple Triangle design although the difference is that GT extend the seatstays to cross the seat tube before joining with the top tube – so, structurally, they’re completely different.

It looks kind of interesting, but what’s the point of BMC’s configuration? They reckon this design, which they use on their high-end carbon road frames and many of their mountain bikes too, ideally distributes forces through the frame. We can’t imagine it making much difference to the ride, but we’ll see when we hit the road. Our 54cm test bike tips the scales at 8.86Kg (19.5lb) a respectable weight, if not a startling one.

It’s not just at the seat cluster where the designers have been busy. The 7005 series alloy has been hydroformed here, there and everywhere. The top tube is flat topped and square edged, for instance, while the chunky seatstays go from box section at the dropouts to tall and pointy by the time they reach the bottom bracket. And what you can’t see is that the tubing is triple butted – meaning that the walls at the two ends are a different thickness to the centre section and to one another – to provide strength where it’s needed while keeping the weight down. Like we said, busy.

BMC’s own SE48 fork comes with straight carbon blades while the drivetrain is mostly from Shimano’s second-tier Ultegra lineup - with a 105 cassette, which is good kit at this price point. The compact chainset is matched up to an 11-28T cassette so we’re guessing that coaxing the BMC up the climbs isn’t going to be too painful, while 105 brake callipers have always looked after us properly in the past so we aren’t anticipating any problems on the way back down either.

Back in the day, the first generation of this frame design was noted for its uncompromising stiffness - one tester who rode the original Team Machine wryly noting that if Tyler Hamilton could ride this for nearly 3000Km around France he truly deserved his king of pain nickname. Since then BMC have refined their designs to make them much more comfortable to ride - in fact rider comfort should be fairly high in the mix on the SR01 as it's part of their Sports Series aimed at the leisure and fitness rider and those getting in to more serious road riding.

Aluminium frame-building technology has moved on a long way from the days when alloy meant harsh and BMC has played its part in that process. These days top end aluminium frames can be tuned to deliver the desired ride characteristics. Interestingly the SR01's seatpost is aluminium - where you might expect to see carbon to take a bit of extra sting out of the road, so BMC must be pretty confident of the ride.

By the way, here’s a little fact for you. What do you reckon BMC stands for? Bicycle Manufacturing Company. We didn’t say it was interesting, we just said it was a fact.

BMC Streetracer SR01

For more info go to www.evanscycles.com/products/bmc/streetracer-sr01-2011-road-bike-ec024691?query=sr01

Mat has worked for loads of bike magazines over 20+ years, and been editor of 220 Triathlon and Cycling Plus. He's been road.cc technical editor for eight years, testing bikes, fettling the latest kit, and trying out the most up-to-the-minute clothing. We send him off around the world to get all the news from launches and shows too. He has won his category in Ironman UK 70.3 and finished on the podium in both marathons he has run. Mat is a Cambridge graduate who did a post-grad in magazine journalism, and he is a past winner of the Cycling Media Award for Specialist Online Writer.