KTM 790 DUKE (2018 - on) Review
At a glance
|Owners' reliability rating:|
|Annual servicing cost:||£190|
Overall ratingNext up: Ride & brakes
KTM have got it so right with its new 790 Duke. Just like the cream of the middleweight naked crop it combines calm practicality with playful excitement.
- Related: 2020 KTM 890 Duke R revealed
It can be a track tool one day and a commuter the next. Its new LC8c engine is a peach, the chassis predictably balanced and it’s all topped off with superbike-spec electronics. After 24 years of the KTM, why didn’t they think of this before?
Ride quality & brakesNext up: Engine
A new tubular steel dual backbone frame is shrink-wrapped around the new engine, so there’s not an ounce of flab. The 790 Duke is as muscular as a pit-bull and weighing just 189kg dry, weighs about as much as its dinner.
With its narrow hips, small riders will find the KTM easy to get on and plant feet down, even with a 825mm high seat (there’s also a 805mm accessory seat and 780mm lowering kit). There’s loads of legroom for six-footers, too. The bar position is natural in its standard position and its bath time-comfy, even after a day’s riding. But as you’d expect from such an unashamed, exposed naked, wind protection is non-existent and your neck feels every mile an hour.
As KTM’s nickname for the 790 Duke suggests, you can go nuts on ‘The Scalpel’. It happily slices through tight twists on the road and will hold its own on a small track, like Brands, Cadwell or Mallory. The chassis is balanced, stable, predictable and the brakes consistently strong. A canted forward riding, feet-back riding has a faint streak of wild supermoto about it.
With little to no means of adjusting the forks and shock the suspension will always be a ‘one size fits all’ compromise. It’s on the firm side of push, but even if there were clickers to play with, the set-up is so bang-on for most road conditions and even the track, you probably won’t bother anyway, unless you were particularly heavy, or extremely fussy.
Cornering ABS lacks a little initial feel, as do most brake-by-wire systems nowadays, but the electronics never intrude unless absolutely needed. The slick autoblipper and quickshifter enhances an already sweet gearbox and you only need to use the light-action slip-assist clutch when you’re pulling away or stopping.
Happily the KTM is less ‘scalpel’ and more ‘butter knife’ when you just want a normal, predictable, motorcycle, for the times you’re just riding to work, or getting caught in the rain. It never strains at its orange leash, or tuts disappointingly when you’re not surgically dissecting pieces of tarmac. The 790 Duke is as calm, reassuring and easy as the best of the middleweight nakeds.
EngineNext up: Reliability
A new 799cc LC8c (‘c’ for ‘compact’) motor is the Austrian firm’s first parallel twin. It’s pared to the bone and impossibly small. How such a tiny lump of metal, with bits whizzing around inside, can produce such grunt (64ftlb of torque) and free-revving power (105bhp) is astonishing. Crammed with forged this, lightweight that and DLC-coated the other, the racy, but refined motor looks no bigger than a single.
Unlike a ploddy one-pot, the new engine is as refined and vibe-free as an inline four, but its 75-degree crank offset and 435-degree firing intervals give the twin an added dash of drama. A deep, gurgling V-twin-like growl accompanies you as you whip out of corners and surge through the revs. Off the throttle the KTM gurgles and spits like a race bike. Even with its Euro4 exhaust the 790 Duke makes a wonderful, rhythmic din.
Reliability & build qualityNext up: Value
It’s too early to say how the 790 Duke will be years down the line, but its rolling chassis is made from tried and tested components and the motor has been subject to over half a million miles-worth of testing.
Value vs rivalsNext up: Equipment
The 790 Duke is cheaper than the MT-09SP and a Street Triple R and pricier than the value-tastic MT-07, MT-09 and base-model Street Triple S, but KTM gives you an awful lot of bang for your buck.
Standard equipment includes electronics not even standard on some Japanese superbikes, let alone middleweight nakeds: lean-sensitive ABS, traction and engine braking control, an up/down blipper and four riding modes (Sport, Street, Rain, Track). There’s also a colour TFT screen with blue tooth, WP suspension, a steering damper, LED lights, adjustable levers and handlebars and a steering damper. You also get a machine that’s the result of over half a million miles of testing, by 60 orange-shirted engineers and test riders, including former MotoGP legend Jeremy McWilliams. KTM are spoiling us.
In other areas the 790 is built down to a price: WP forks are non-adjustable and you can only twiddle the shock preload. It has own-brand four-piston radial brake calipers (actually made by Spanish experts J.Juan – as seen on Rea and Syke’s WSB leathers) and Maxxis tyres.
|Engine type||Liquid-cooled, 8v, parallel twin|
|Frame type||Tubular steel dual backbone|
|Fuel capacity||14 litres|
|Front suspension||WP 43mm non-adjustable USD fork|
|Rear suspension||WP Single rear shock, adjustable for preload|
|Front brake||2 x 300mm discs with four-piston radial caliper|
|Rear brake||240mm single disc with single-piston caliper|
|Front tyre size||120/70 x 17|
|Rear tyre size||180/55 x 17|
Mpg, costs & insurance
|Average fuel consumption||-|
|Annual road tax||£93|
|Annual service cost||£190|
|Used price||£5,400 - £7,500|
How much to insure?
|Warranty term||Two years|
Top speed & performance
|Max power||105 bhp|
|Max torque||64 ft-lb|
|Top speed||135 mph|
|1/4 mile acceleration||-|
Model history & versions
2018: 790 Duke launched, featuring KTM’s first parallel twin cylinder engine and a full suite of electronics.
MCN Long term test reports
MCN Fleet: Your KTM 790 Duke questions answered
Q Do you miss having adjustable suspension? Johnny Hinds, on email In a way their absence of any damping adjusters is liberating, particularly at trackdays. This is an uncluttered motorcycle with a heart of gold and a straightforward attack plan: just get on with it, idiot, it seems to say. Turn the…
Owners' reviews for the KTM 790 DUKE (2018 - on)
16 owners have reviewed their KTM 790 DUKE (2018 - on) and rated it in a number of areas. Read what they have to say and what they like and dislike about the bike below.
Summary of owners' reviews
|Ride quality & brakes:|
|Reliability & build quality:|
|Value vs rivals:|
|Annual servicing cost:||£190|
Great all rounder. Low speed fueling in town is rubbish, bike runs too lean due to the blasted euro4 emmisions regs but is great above 35mph. Quick shifter is great fun. Bike is light to handle/park. Very nimble superb handling in the twisties. Easy to get to 120mph but after that wind blast is a bit severe.
Could do with a lot more feel and initial bite but they stop the bike and are consistent.
Amazing. Feels like a cross between a single and a V-Twin. Torque all over. Plenty of power. Quick enough. Gearbox is great. Quick shifter is good fun.
Mine has been very reliable so far.
Changed Maxis tyres for Michelin Pilot Road 5 which are great in the wet. KTM bar end mirrors went all floppy so went back to stock. Akrapovic slip on only worth it if you remove the welded in DB killer, then it’s awesome, otherwise look elsewhere. The large digital speedo is very easy to read. Blingy orange optional powerpart levers look good.
Buying experience: Paid main dealer £8000 in 2019 for a 6 month old 2018 that had £2k worth of extras on it from previous owner with 400 miles on the clock.
Ktm have covered so much with this model and parting with your cash this bike makes biking fun.
The riding position is excellent. Brakes are awesome and with the engine braking stopping power and bite are faultless. Can do 2 hour rides without any aches or feeling tired my previous old school superbikes can make a man weep after 40 minutes
I’ve never ridden a parallel twin with offset firing order and this bike sounds amazing even with a standard pipe. It spins up super quick and fires you out the corners. It’s usable everywhere and you forget this is just shy of 800cc it looks tiny. Engine breaking works well in twistys.
It’s a super new bike and won’t see winter salt but the bike looks new. Under the headstock slight corrosion but only surface.
Similar if not cheaper than my previous super bikes
Let’s start with getting rid of the standard mirrors and opt for genuine ktm bar mirrors as the standard ones look awful and do not work well. Change the Maxxis tyres yesterday they are way to budget for this bike anything under 15c they slip bad. And a tail tidy. The add ins are endless. The digital dash is brilliant and all the settings and modes this bike does things top end superbikes don’t, excellent quick shifter but only when you are on the gas. And changing riding modes truly changes the bike in each one.
Buying experience: Bought it second hand only one years worth of use. On for £6400 paid £6000 the overall value of this bike cannot be overlooked.
Annual servicing cost: £120
Started leaking oil on head gasket after 600km.....constantly pissing radiator fluid
Version: Doris Day Edition
Annual servicing cost: £200
Great all round naked roadster with a gem of a motor with an electronics package to match the best of them. I would recommend this bike to anyone looking for something fun and capable that can easily be adapted to suit an individuals specific requirements.
Best on smoother roads as the suspension is quite firm which is great for sportier riding but can be a little choppy otherwise. Brakes are quite good but lack a little feel and initial bite and need a firmer hand to stop quickly from higher speeds. Stock Maxxis tyres need a lot of warming up before they offer decent grip and again lack feel when pushing on. There are fixes for all these things - at a price!
Superb performance with a good spread of torque and enough power for any situation combined with excellent fuel economy. The only slight niggle is a little nervousness on a constant throttle at lower speeds particularly in Sport mode. There are fixes for this - at a price!
For sportier riders change the tyres to Michelin Pilot Power RS/4 or Bridgestone S22 Front brake pads to EBC HH and steering damper fluid to15-20wt Join a forum to get more out of ownership : https://www.790dukeforum.com/forums/
Annual servicing cost: £187
This is without doubt the most fun bike I have ever owned (I've owned 28 over the years including this one). Every ride makes me grin like a Cheshire cat. Ergonomics are brilliant (usual KTM adjustability), the engine is a peach and the electronics are amazing at this price point. Cannot recommend it highly enough
Excellent setup straight from the crate. Lack of suspension adjustment is not really an issue as it is so good as standard. Brilliant B road scratcher. Great for track days. Even tours and commutes with a Ventura rack fitted. Absolutely brilliant all rounder.
Amazing motor. Great punch, perfectly geared. Lovely sound too. Electronics are amazing. Up / down quickshifter is brilliant. Riding modes are easy to access and the controls and dash are nice and clear and easy to use.
Output shaft oil seal failed early on as the bike was delivered with the chain set too tight. This was fixed under warranty at the second attempt. Dealer was good.
KTM dealer labour rates are a bit steep.
Electronics at this price point are class leading. KTM Powerparts catalogue is extensive. I fitted the 20mm taller Ergo seat which gives me a little more leg room and is a bit more comfortable than the stock seat. Also fitted a Givi Tanklock Tankbag and Venture luggage rack for touring and commuting.
Buying experience: Gear 4 in Market Deeping were great. Competitive pricing. Decent PX. Good service.
Version: DUKE Black
Annual servicing cost: £178
Many cheap products
The j.juan brakes and Galfer disk work satisfing together.
Gearbox/Quickshifter are capricious!
The didn’t solve the problems with the Quick Shifter so I paid a lot of money for only changing oil and filter....
MAXXIS Tyres are OK on dry roads, at wet the are unpredictable.
Buying experience: 11990€ in the Netherlands we have extra taxes on motorbikes
Appauling it has spent more time in a workshop being fixed than what I've been able to ride it continuesly has issues listed below and KTM couldn't give a monkey's about you once they have you're money i have never come across such bad customer service
When it works it's good fun but it has spent more time in a garage being fixed than what I've been able to ride it
Again when it works it's good but it is weak as continuously breaks down
Absolutely appauling build quality in 8000 miles i have had 5 oil leaks, thermostat, thermostat housing, 2 sets of clocks, panels, rear brake assembly, warped disc, head bearings, and continuesly cutting out regardless to speed etc, subframe bolts and the loan 790 that has only covered 342 miles has an oil leak from the sump gasket and also cuts out it has spent more time in the workshop than what i have been able to ride it yet KTM says it's still fit for purpose that was when they eventually got back to the dealer after ignoring 5 emails from myself
Lots of technology however i think KTM need to focus more on the basics like making a bike that doesnt break every 150 miles
Buying experience: Dealer was extremely helpful which is more than i can say for KTM UK customer services as they ignore emails and dont respond at one point they were even ignoring the dealer i brought it from
Annual servicing cost: £198
Brilliant to ride, comfortable, good on fuel, fast and so so much fun
The brakes are plenty good enough for me and the ride quality is really good in my opinion. It's so much fun to ride that even with some initial quality issues, I will get another one in due course. We recently did 2000 miles to the Black forest and had an absolutely brilliant time, the bikes were brilliant. Very comfortable and really good on fuel.
The engine is outstanding and easily keeps up with larger capacity bikes. It's a very lite bike and is capable of embarrassing bigger bikes in twisties.
Soooo much fun but some reliability issues. Failed rear shock on one bike, leaking fork seal and warped front discs on the other
My wife and I both own 790 dukes and have just had the 12 month service completed on both. My wife's bike needed a new rear shock as it had leaked all of the oil from it. My bike needed the front discs replacing as they were warped (I'm not heavy on the brakes at all. ). It also required new seels on the front shocks as one was leaking quite badly. Everything done on warranty - dealer service was excellent
Loads of electronic wizardry, really good
Buying experience: Colwyn Bay KTM were (and continue to be) excellent). Our bikes were bought from the main dealer
Annual servicing cost: £220
Fantastic bike, but a few reliability problems let it down
To drive this bike is amazing, you'll always finish your trip grinning from ear to ear! Very comfortable and very quick!
The power from such a small (physically) engine is unreal. Even with anti-wheelie on the bike still easily lift the front wheel.
Rust has formed on the triple clamp after just 3 months and exhaust has a hole in it awsell as liquid leaking out of the lambda sensor. Since the maps were updated it cuts out when cold but completely fine when warmed up. KTM however, are rectifying all problems under the warranty.
Great on fuel. A yearly service costs £220 which I find quite expensive.
Comes with plenty of toys as standard. The quick shifter is great as the power delivery never stops and the pops and bangs when you shift down with the blipper make slowing down highly enjoyable.
Annual servicing cost: £172
Potentially brilliant bike let down by build quality.
Brakes are good, but the unadjustable suspension is awful on our bumpy English roads, any small road imperfections cause the forks to crash and jar you hands. On smooth roads it’s fine though.
The best bit of the bike in performance terms is the lovely quick shifter/blipper. The bike is massively let down by three different oil leaks to date in under 700 miles. It’s sad but It may be the first and last KTM I purchase as it was also supplied brand new with lots of other cosmetic faults. Scratched tank, scratched subframe, damaged clutch lever, peeling graphics...........REALLY POOR.
Multiple quality issues.
Not the cheapest first service.
Great equipment as standard but a comfort seat really made a good addition.
Buying experience: Purchased new.
The KTM is a fantastic piece if kit and very good all rounder.
It's a very easy bike to ride, a bit like a 125 that's beefed up. Very enjoyable and fantastic brakes.
It has a lovely sounding engine and pulls very well throughout gears and rev range.
I have 5700 miles on mine it now has its second oil leak as well as overheating issues because it goes through an entire reservoir of coolant in two days. My heads up display has had 11 cracks appear over night and I've had to replace the front sprocket as the first one fell apart plus a set of fork seals which were leaking when i picked the bike up.
This would be a 5-star rating, but the Maxxis tyres that come on it are pants if there is any moisture and they don't hold any heat.
Great fun all rounder !
Brakes initial bite is quite soft, but plenty of power and great feel.
Love the sound and all the mechanical clattering and the burbles and gurgles on the overrun
So far so good. Never had a KTM before.
Decent service intervals
Fantastic electronics package, quickshifter, auto blipper, modes etc etc..great
Buying experience: Fantastic deal from 'The Potteries Motorcycle and Scooter'
Version: Black one
This is the best bike I have owned. Had numerous bikes but never been able to exploit their full potential on the road because I am mildly sensible. Not this one, I ride it like a twot and it’s so easy. Smile, smile, smile - the modern RD350 but si much more.
The brakes work and I ride it without worrying about what setting it’s on because I’m having so much - FUN !
A modern classic,game changing,lovely bit of tech ! I have a 1999 R1 which I’m moth balling because the KTM is so good.
Nothings fell off yet !
Quick shifter and auro blipper work really well, makes a BMW look agricultural. No idea what I’ll do with lean ABS and launch control but got to be worth a go !
Buying experience: Gear4ktm - Paul or Luke are the men. Paul - Waiting for my touring screen to do the Alps and beyond.
I’ve down sized from the 1290 Super Duke by accident as was given a 790 demo bike while mine was serviced and loved the engine and gearbox from the off. It’s so much fun and I feel like I need to attack each corner and it never fails to put a big cheesy grin on my face.
Not the most competent brakes and think it’s because I’ve been spoilt previously with Brembo set ups.
I’ve had no problems as yet and only had it 2 months, 1000 miles. So far runs like a dream.
I still find it drinks a lot but I tend to be in track and sport mode and riding like my hairs on fire so I put the bad fuel economy down to me.
Has all the whistles and bells and I absolutely love it.
Annual servicing cost: £250
What a bike! Does everything with ease, very confidence inspiring keeps up with any superbike round the twisties.
Ride quality is superb, the engine is so sweet. No vibration at all. Brakes are sharp.
Although it's got less power than my last bike, I love this engine, so much punch! Shame they didn't add like another 2-3 thousand rpms to the rev limit though because it feels so sweet, high revs it just runs out a bit quick.
Couple of small issues, launch control doesn't work.. Paint gone funny on the body around the tank and coolant level keeps going down but currently being fixed under warranty.
Parts are fairly expensive, fuel consumption is fantastic though. Only had first service which was about £90 just for parts. That's an expensive oil filter plus oil.
The best parts of the bike are the handling (probably thanks to the super clever traction control and cornering ABS) and quickshifter up and down, the bike literally makes me look like a pro.
The bike is really nice, unfortunately I would not recommend the bike due to the fact it developed an electrical fault within 6 hours of riding it away from the dealership.
Bike rode nicely before it broke down.
Had to have it recovered before i even got it home due to an electrical fault, I literally had the bike 6 hours. This obviously gives me great concern going forwards.
Good overall value given the amount of tech on it.
Bags of equipment, mirrors are crap but they are on most new bikes.
Buying experience: Purchased from a dealer, new.