KTM’s 1290: why they call it PR ‘spin’
KTM test rider and ex-500cc GP racer Jeremy McWilliams says the new 1290 Super Duke is the torquiest bike he’s ridden. KTM claim it makes more at 2000rpm than the 990 Super Duke at peak (70 lb.ft). That’s a lot of big torque talk.
Torque is often wrongly thought of as a measure of engine performance at low rpm. Big V-twins have ‘lots of low-down torque’, and inline four sportsbikes ‘lots of top-end power’, as if the two are discrete and opposite. They are different, but not opposites...
KTM’s 1290: why they call it PR ‘spin’
KTM test rider and ex-500cc GP racer Jeremy McWilliams says the new 1290 Super Duke is the torquiest bike he’s ridden. KTM claim it makes more at 2000rpm than the 990 Super Duke at peak (70 lb.ft). That’s a lot of big torque talk.
Torque is often wrongly thought of as a measure of engine performance at low rpm. Big V-twins have ‘lots of low-down torque’, and inline four sportsbikes ‘lots of top-end power’, as if the two are discrete and opposite. They are different, but not opposites. Torque is the primary measurement; power is calculated from it. Think of it like this: torque is the size of an engine’s punch, power is how fast it can throw it. They’re not exclusive.
Torque is a force making an object turn around a centre, such as twirling a spanner, turning a door knob or, in our case, pistons and con-rods spinning a crank. When a dyno technician talks about torque, that’s what he means (unless he’s bolting down a cylinder head). In the UK 1 lb.ft (or 1.4 metric Newton-metres) is defined as one pound of force acting one foot from its pivot. At 2000rpm, the 1290 Super Duke’s crank will turn as if it had a one foot lever with 32 bags of sugar piled on the end.
But that’s a snapshot. Engine torque changes with revs, as per a curve on a dyno plot. Two things matter: the shape of the curve, and the quantity of torque. The shape (and where peak torque occurs) is influenced by fundamentals like the number of cylinders, their layout, the bore, stroke and cam timing. If you’re designing a new engine, these are the foundations for its character. KTM based the 1290 engine on the Adventure 1190, so the shape of its torque curve is likely to be similar.
But quantity of torque derives mainly from engine displacement: ‘ain’t no substitute for cubes, although volumetric efficiency (how well fuel and air get into and out of the combustion chambers) and thermodynamic efficiency (how well it burns it in between) also matter.
But even with the 1290 actually clearing 1301cc, it’s basically a bored-out, stroked 1190 which KTM say makes 106 lb.ft at 6500rpm (90 to 95 lb.ft on the dyno). The nearest comparable V-twin is the Panigale R, at 90 lb.ft. But it’s unlikely the 1290 makes 70 lb.ft at 2000rpm as per the 990 Super Duke at peak, because it’s so far off peak efficiency. We can’t prove it because we dyno test in fifth gear and anything under 3000rpm stalls at full throttle. But so will the bike on the road, so it’s a spurious claim.
Either way, if the 1290 is the torquiest bike McWilliams has ridden, you wonder how gutless Kenny Roberts’ 2005 Proton V5 MotoGP bike was. And Jezza might like to try Suzuki’s Hayabusa, BMW’s K1600, Kawasaki’s ZZR1400, Honda’s GL1800 Gold Wing. And especially Triumph’s 2.3 litre Rocket III.
Because now, at 150 lb.ft, you’re really torqueing.
Kevin's funeral was held on Thursday 28th February 2013 and was well attended by family, friends and colleagues.
The Telegraph has very kindly established The Telegraph Kevin Ash Fund to assist with the education of Kevin's three daughters.
If you'd like to make a donation then you can use the PayPal 'Donate' button below which will allow you to donate from your PayPal account, or via credit or debit card. A small percentage (about 3.4%) will be retained by PayPal for the service.
Kevin's family have been touched by the generosity and messages of support from people using the website and would like to express their gratitude to those who have contributed in any way.
The donations keep coming in, thank you so much, and the family especially like it when you leave a message.
Home | facebook.com/KevinAshFund | twitter.com/KevinAshFund | © 2014