Kraftfahrzeuge Trunkenpolz Mattighofen (or KTM as it is commonly known) started life in 1934 in Austria when Hans Trunkenpolz opened a repair workshop in Mattinghoffen. The workshop first began supplying motorcycles in the late 1930s and, by 1951, development of their first production model, the R100 had begun.
KTM’s success at producing small-capacity racing bikes through the 1950s, 60s and 70s translated into off-road success in the 70s, winning multiple motocross and enduro championships.
By the nineties, KTM (now known as KTM Sportmotorcycle GmbH following bankruptcy of the original company in 1991) was predominantly known for their wide range of off-road motorcycles, but released their first road going motorcycle of the modern era in 1994 with the Duke LC4 620. Released as the ‘fun bike’, the 620 was made with 80% enduro parts, was powered by a single-cylinder engine and weighed 145kg.
The energetic and free-revving singles used in the Duke up to the 690 make for an excellent exhaust note and give the bike a charismatic, charging puppy energy. Lots of low-down grunt has you barrelling out of every corner regardless of the gear you are in or blitzing past traffic in a city centre.
KTM Duke I and KTM Duke II
The KTM Duke was the first bike KTM produced purely for use on the road. Sharing 80% of its parts with the LC4 620 enduro machine, the Duke produced 50bhp and 42ftlb of torque from its 609cc single, but with shorter-travel suspension and smaller laced wheels.
All of this added up to a package that was raw and exciting to ride, especially given the Duke’s low, 145kg weight.
The KTM 640 Duke or Duke II was a completely redesigned motorbike that built on the first Duke’s winning formula. It used the same 625cc engine as the last edition Duke I but added a new, constant pressure carb and dual exhaust.
This version ran until 2003, when a redesigned model was launched with a more powerful, 55bhp engine. At the time of launch, the redesigned Duke II was the most powerful street-legal single-cylinder money could buy (a mantle now taken up by the 74bhp unit in the KTM 690 Enduro R and Husqvarna 701 Svartpilen).
KTM 690 Duke
In 2008, the KTM 690 Duke was introduced, representing the biggest change to the model since its conception. Aside from a drastic restyling, the carb made way for a new injection system, the displacement grew to 654cc, a slipper clutch was added and selectable rider modes were available for the first time.
In 2010, the KTM 690 Duke R was introduced with an extra 5bhp and half a kilo of weight saving.
KTM relaunched the 690 Duke again in 2016 with even more power from its single cylinder engine. A reworked cylinder head and bore/stroke ratio mean 73bhp is squeezed from the same 690cc capacity.
The engine is incredibly free-revving for a thumper too, with peak power coming at 8500rpm, where many singles would be bouncing off their limiter.
KTM 125 Duke and KTM 390 Duke
Many motorbike manufacturers build bike ranges that cater for riders at all stages of their motorbike licence progression, and KTM are no different. The A1 licence-friendly KTM 125 Duke was launched in 2011, followed by the KTM 390 Duke for A2 licence-holders in 2013.
In 2017, and with a new raft of competition in the A1 market, KTM launched a remodelled 125 Duke that took its styling cues from the KTM 1290 Superduke R. The new bike also got a new TFT dash (market-leading for a bike of this type at the time), a bigger tank and improvements to the already strong brakes and suspension.
KTM’s Duke option for A2 licence holders sits in the middle ground between the 125 and the focused 690 models. The KTM 390 Duke uses its 373cc single to produce 44bhp, and that’s enough for a lively, engaging experience around town.
KTM 790 Duke
In 2018, the KTM 790 Duke was released, boasting 105bhp from the manufacturer’s first ever parallel-twin engine. KTM engineers nicknamed the bike ‘The Scalpel’, and it really deserves the mantle.
In the right hands, the 790 would clean up at a track like Cadwell Park with its tight turns and relatively short straights, but it is also a formidable weapon along any twisty B-road.
KTM Super Duke
KTM went to the drawing board and in 2005 unveiled their answer to the growing craze for naked superbikes, the 990 Super Duke. MCN declared at the time, "There is surely nothing more frenetic on two-wheels than the KTM 990 Super Duke short of sticking a nitrous kit, a jet turbine and a flame-thrower into the frame of a fold-up bicycle."
KTM 1290 Super Duke R
In 2013 the 1290 Super Duke R was unveiled with 160bhp (originally claimed to be 180bhp) and an astonishing 99ftlb of torque available from its 1301cc V-twin engine.
The 1290 sounds like a terrifying prospect but it’s actually a light and easy to ride naked machine, especially when you consider that it was the most powerful naked bike on the market at the time it was released.
The 1290 Super Duke R was upgraded in 2017, and MCN Chief Road Tester, Michael Neeves was looking forward to getting his hands on one at the launch. "The tweaks to the new Super Duke R move it a big leap forward. It’s still ballistic on track and surprisingly civilised on the road, but the new electronics add extra safety and speed to the party, too. The KTM is now ready to take on its rivals."
1290 Super Duke GT
With 173bhp on tap, the KTM Super Duke GT is more powerful than you might expect for a bike with an upright riding position and hard panniers. As well as all this power, you also get traction control, cornering ABS and WP semi-active suspension, heated grips, cruise control, quickshifter (up only) and tyre pressure sensors – all as standard.
The GT’s touring credentials are beefed up with a 23-litre fuel tank, which gives the bike a 225-mile range (dependent on your right wrist).
KTM Duke rival motorbikes
The various iterations of Duke throughout its evolution have faced competition from various manufacturers. The Duke I and Duke II sort of ran against bikes in the newly forming adventure market such as the BMW R1100GS, Honda Africa Twin, Yamaha XTZ660 Ténéré, Cagiva Elefant and Triumph Tiger 900, although the KTM’s supermoto influence and smaller-capacity engine meant that it was never a perfect fit.
The Duke 690 faced competition from bikes like the Yamaha XT660X, which ran a similar capacity four-stroke single (but only produced 47bhp) and later the parallel-twin Yamaha MT-07. Later incarnations also had to contend with more focused supermoto offerings like the Ducati Hypermotard and Aprilia Dorsoduro.
It woud also be worth considering the economic and characterful Suzuki SV650. Although the Suzuki is a V-twin naked sportsbike, the power output is similar and it ticks a lot of the same boxes as the Duke.
The 990 and 1290 Super Dukes fall into the super-naked category where the Yamaha MT-10, BMW S1000R and Honda CB1000R ply their trade. It also falls into the sights of sports tourers like the BMW S1000XR, Ducati 1200 Multistrada and Kawasaki Versys 1000, especially in GT spec.
There are plenty of naked 125s on the market to rival the Duke 125, the Yamaha MT-125 is the most obvious, but there are also the Honda CB125R, Kawasaki Z125, Aprilia Tuono 125 and Suzuki GSX-S125.
Likewise, in the A2 licence category, there are plenty of options to choose from. The Yamaha MT-03, Kawasaki Z400, Honda CB300R and BMW G310R are obvious contenders.
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