SUZUKI TURBO GATHERS PACE
Turbocharging is set to become widespread on future bikes as manufacturers combat emissions limits while striving for improved economy and performance. And Suzuki will be at the forefront of the forced-induction revolution as a production version of the Recursion concept bike is creeping ever closer to showrooms.
Since the Recursion broke cover at the 2013 Tokyo Motor Show, Suzuki havenõt denied a production turbo bike will follow it. Two years later, at the 2015 Tokyo show, a near-production turbo engine, the XE7, was unveiled. Now patents have emerged that show how the two will be combined into a production machine.
Suck, squeeze, bang, blow
The Recursion used an SOHC, 588cc parallel twin with a turbo mounted behind the front wheel. Blowing through an intercooler mounted under the seat it made 100bhp and an impressive 74ftlb of torque.
The XE7 engine is better still. While no figures have ever been revealed, itõs a similar size to the Recursionõs engine and uses a DOHC head, hinting at more performance. Itõs also packaged better, with the intercooler mounted above the cylinder head to fit the whole thing into a smaller space. Importantly, the 2015 XE7 show engine was production-ready; there were even visible part numbers cast into some of the components.
Performance is hard to guess at since tweaking boost can make vast changes to the power of a turbo engine. Expect at least 600cc sportsbike power levels combined with as much torque as a 1000cc superbike, all delivered at relatively low revs. One new patent hints at a five-speed gearbox; the wide torque spread could make any more than that unnecessary, and fewer gears will allow larger, stronger ones to be used.
Suzuki have filed more than a dozen new patents relating to details of the new turbo bikeõs frame, engine balancer shaft and the cooling system. Gone is the Recursionõs aluminium chassis, replaced by a steel trellis that lets the additional pipework of the forced-induction system snake through holes in the chassis.
While the patents show Recursionstyle bodywork and a single-sided swingarm, these elements arenõt key to the patented ideas and could be changed for the production bike. In terms of appearance, for instance, the final bike is sure to get a pillion seat.
Having revealed steps towards its turbocharged future at each of the last two Tokyo Motor Shows, in 2013 and 2015, it will be no surprise if Suzuki reveal the finished production bike at the 2017 event this October.
Recursion concept edges closer to reality
Parallel twin XE7 engine could make as much torque as a litre superbike
Latest patents show steel trellis frame