2018-2020 KTM 790 Duke Review: KTM have got it so right with its 790 Duke, but it is flawed

The brakes are wooden but different pads could help that. The JJUan master cylinder is not great, it leaks a little dot fluid from the lid and the lever feel is quite spongy. JJuan is the spanish company that makes some of the KTM calipers and other brake components. I think the suspension for a I unadjustable unit is totally acceptable. They work well.

It's a nice engine, happy to be revved and has good bottom end and mid range power. Doesn't seem to create a lot of vibrations either.

Engine cutting out at slow speed. Left switchgear not very protected against rain ingress, indicator light stays on when the switch gets wet. Oil leaking from rocker cover. Coolant doesn't want to stay on the inside of the engine overheating problems due to leaks. Discs warped, new ones fitted under warranty then they warped after 3000 miles. KTM replaced the front wheel and new discs and this sorted the issue. They said the bolt holes in the wheel hub is off by around 1mm so the disc is never central with the caliper.

Running costs is a 3 out of 5 because if you need to spend money fixing problems it's not cheap. It's good on fuel. Had the bike serviced by independent garage and it cost me £150 this included valve clearance check.

As mine is an early model 790 it has the tech pack as standard but if I had to pay Ktm a couple of hundred pound for that track pack I would have given a much lower score in this category. Everything for the track pack is already on the bike, KTM just electronically locked it behind a pay wall. All they do is plug in a computer in to the ECU and choose enable optio.

The 'Scalpel' is an apt nickname, it's such a lovely balsnce of power and grest handling for the road. I've owned 12 bikes over 25 years of road riding and this is probably one of my favourites. The suspension still needs set up for my weight (I'm clueless in this area) and some new rubber, but it's still amazing through bends and inspires confidence but new rubber and a proper set up, together would be transformative.Brakes are great but lack a bit of feel, but overall t's such a useable, friendly but feisty, fun package 📦 ✨️ Definitely a keeper!

This is the best bit of the bike, 790 parallel twin putting out great bhp and torque, perfect for the road. I've added a Black Widow decat pipe and silencer along with a performance air filter and it's turned into a bit of a mini beast!

Bought second hand, a few rusting bolt heads indicating it's seen a couple of winters but on the whole it's in great nick and cleans up really well. Strong build quality, although the light and turn switches feel slightly 'budget'. No electrical gremlins or rattles.

Servicing is fairly straight forward on the parallel twin and it is very frugal in Street and Rain mode ...and Sport as well tbf. Feels like it should be guzzling more by the way the engine puts down usable power. Great balance 👌

See above. The Black Widow is a proper bargain btw and they're available for a chat when purchasing. Looking forward to some new Metzeler tyres. Lots of extras available to bother your wallet/purse!

I fitted aftermarket rear shock and a racing cartridge.

Would love brembo breaks as they are the best but they are ok

All I can say is every time I use the bike I end up with a BIG smile, I love it and don’t need any more power. The 0-60 and 0-100 is unbelievable. It performed great on a track day.

The paint is flaking on the engine all over it’s like they only showed the bike the paint to show what it’s supposed to look like. I had loads go wrong in the first 2 years fortunately it was under warranty apart from the warped front break discs

The original tyres only lasted 3000 miles but replaced with Michelin road 5 and the lasted over 10000 miles

Love the different riding modes. Don’t bother paying for the Bluetooth to be added to the bike , not worth it. Get Michelin road 5 tyres they are great

Really jerky at low revs (below 3k). It demands to be ridden faster. You get used to it, but it is a shame that it is so bad at slow speed/town. Once moving, suspension and brakes work very well

Great character, some reliability issues but they don't take away from the engine enjoyability once resolved.

Leaking valve cover. Shouldn't happen with a modern bike, although not an expensive fix

54 mpg and sporty is a win

Plenty more than 890 Duke because you don't have to pay to unlock any features . Really spoilt with features and plenty of accessories available. Exhaust limits luggage on the one side, but there are ways around that.

As a non R the suspension is a bit on a harsh side once you start to push the bike. Front brake works very well but it takes quite a lot of movement on the lever before the pads start to bite but once they do it has good modulation. Rear brake works as you would expect. I have ridden a below freezing for 3 hours on the motorway on my D790, the standard seat seems fine and generally there's not much vibrations.

Put this in to rain mode and docile, relaxed and gentile. Put it into sport mode and the charismatic of the bike totally changes, it becomes a bit of a hooligan machine, quite happy to lift the front wheel in the first 3 gears. What I really dislike is the standard fueling, I could only filter in rain mode because anything higher would snatchy and for that reason I ended up buying the "boosterplug" which now means I can use street mode and have full power when riding in the city without switching back down to rain for filtering. Standard exhaust might be ugly but it sounds great.

Mine kept cutting out, then I was recommend to get a lithium battery and it solved the issue, maybe they are a little bit sensitive in regards to voltage. Once the voltage drops a little bit it can flag up a few errors. It only cut out at very slow speed, filtering in traffic. Since adding the lithium battery I have had 0 issues with the bike. Seems solid enough in regards to build but feel like power coating of engine casing could be better and more robust.

This bike is no different to service than your normal Jap stuff. Mine averages 55mpg so I won't complain, cheap bike to run so far.

I think for the money at the time it was the best equipped bike in it's class. I don't really alter much apart from the modes, quick shifter up/down works very well. Headlight is maybe the best I have used and the dash is crystal clear. Dash menu is also very easy to use.

Best bit - it's a peach!

It shouldn't be as good but super light revving and instant, predictable addictive power - best fun I've had for many years

Few bolts off colour but use of protective spray and regular cleaning keeps it looking tip top

Parallel twin, easy to work on and regular service and MOT are standard price - bargain for the fun factor

Balance of super handling and power - it's like you plug in Avatar-style!

Only 4500 on it so low mileage but all good so far .no problems

Brakes on the 790 could be better, spongy slightly after a long ride - the 890R has brembos which probably solve this. Handles better than your ability and actually very easy to ride, you could even have as a first big bike starting out only on Street mode before graduating to Sport mode

All the power you need and sounds amazing

Absolutely no problems in over 2000 miles, always started but some surface marks on engine

Each yearly service was £200-£300. The 790 was always good value, but the new 890 is not good value, would be better to just get the 890R instead with the Brembos instead of a base 890 (just buy a used 790 instead)

Came with engine modes and quickshifter included - you'd pay extra with a new 890

Front brake a bit poor effort compared to my previous honda . New brake pads made this better

Brilliant engine 3rd gear just keeps giving .bit snatchy under 25 mph

All OK but only got 2500 miles on it

I use my bike for quick blasts, longer runs, and touring. It does all those well with some small additions, carrier, occasional use of a top box, added a USB power socket.

Absolutely brilliant, a little jerky at slow speeds, but good clutch control can obviate this.

Water ingress in indicator switch gear.

Switched to Michelin Road 5's, very good.

Quick shifter absolutely fantastic

The KTM runs and rides fantastically, a true testament to "budget" middleweight naked bikes. The frame is stiff, but not stiff enough to render the suspension and tires useless. As I mentioned previously, it's a perfect hybrid of sporty naked middleweight and supermoto. In terms of pure mechanical grip, this is up there, considering it has a non-adjustable front end. The Duke is always up for a challenge, taking tight and technical bends with ease and begging for more. My only issue in terms of pure ride quality are the tires, the front suspension and the breaks...that's it. The front suspension is a non-adjustable set of WP forks. They are fixed in a damn good spot, to KTM's credit, but for someone who looks to exploit a bike for a little more performance, I felt that the front end was a let down. The tires are... different. They aren't terrible, but for a British road-goer on a wet and cold road, they aren't the best. I had the pleasure of experiencing these tires in the summer and they were fantastic, but the chassis and the front suspension definitely flattered them. The breaks are pretty good, considering they are KTM's own breaks. You have twin disks at the front and a single baby rotor at the back, standard. The ABS is what's actually the more impressive piece of the braking package. KTM use Bosch as their supplier for their bike's software, a match made in heaven if you ask me. The ABS is a brilliant addition to this bike as it offers a better safety net for newer riders as well as an adjustable side for the more seasoned rider. The thing that bugs me about this system, however, is the intrusive side of the ABS. For me, personally, it's far too intrusive for normal road riding. The back break is constantly twitching under my toe and the front ABS is dim-whitted a lot of the time. With features like Supermoto Mode or ABS OFF, the problem can be resolved. Credit where credit is due though, cold tires on a slippery road during winter is the ABS specialty; I'll always thank the system there.

There isn't a lot to say about the engine, other than perfection. As we all know, British roads are becoming more and more of a camera fest; the 1000cc sports bike is quickly becoming a thing of the past as average road users cannot find a use for such amounts of power. KTM's LC8c engine is a different story; producing 105 horsepower and 64.2lb-ft, the little parallel pumper goes a long way in terms of street cred and top trumps. In reality, the KTM will probably look under-powered when compared to the 765 Street Triple R and the MT-09SP, but there won't be a lot between them in terms of dynamic speed and acceleration. I tested this by pitching a 790 Duke (bone stock) against a 2011 Triumph Street Triple 675R (Triumph headers, no cat and some spicy aftermarket exhausts)... The 790 walked away with ease. An unfair test, maybe? But it was a practical demonstration of torque and displacement over pure horsepower. There are no lumpy traits to the engine, thanks to KTM's wizardry with various balancing shafts and firing order. Thanks to these efforts from KTM, we now have an 800cc parallel twin that is completely smooth with a brilliant ride-by-wire system and electronics package. The engine itself, is a peach. The engine, strung together with all the best elements of this bike, is an utter animal.

I was pleasantly surprised with the standard of quality at which the bike is at when I first saw the bike in person. Everything from switch gear and handlebar controls to the paint finish on the frame, tank and swingarm. The KTM doesn't feel as budget as it's cost may appear to be. The plastics are of really good quality, to be expected as KTM produce outstanding motocross plastics for their bikes too. The frame feels really good and is good to look at; no rough welds or uneven metal splatters on any of the joints. The engine, when running, produces a lovely grunt and sounds very refined; ticking over to the beat. The electronics package is what makes this bike feel so premier, but I'll get onto that a little later.The reliability of the bike is sound, no major faults or anything work taking notice of. The bike, as it comes from the showroom, is as stock as stock can be. The fueling is iffy, the quickshifter can be a bit dim-whitted and the idling can be too low. After the 600 mile service, however, the bike did not miss a beat. Everything worked as it was supposed to. The fueling improved (with a little help with a change of climate too), the quickshifter was absolutely crisp and the idling speed was bunged up a few hundred RPM to assure there were no stalling errors. KTM did an outstanding job fine tuning the bike to how I like it.

In terms of value, I genuinely don't think there is a lot out there for the same money that will out-perform the KTM. From the electronics package, to the stiffer chassis and suspension which screams supermoto/supernaked lovechild, the bike feels top class for it's price and performance. The 790 went through a summer deal offer during the summer of 2020 which saw the price plummet to a juicy £7500, a big saving on the grand scheme of things. The KTM has a lot to offer when it comes to parts, software and quality, which is why I rate it so highly.The running costs for this bike are around standard for a regular street bike: - The fuel consumption is neither here nor there when riding the 790 casually, however, an eco trip will boost it's range by a considerable margin. On the other end of the spectrum, if you decide to ride the bike as KTM intended it to be ridden (with a smile), the fuel consumption is up there with the be... sorry, worst. - Services on the bike from the dealership range between £80 to £100 depending on what you want from the boys at KTM, as well as how often you want to have it serviced too! - Insurance is really dependent on where you live and your age, as per. For a new rider fresh from the A2 batch, it'll probably be a little pricier as insurers will look at your age along side the bike. - KTM will tax your bike if bought brand new as a gesture of thanks for buying their product. After a year, the bike will share a similar tax bracket to that of an MT-09 or a 765 Street Triple.

The 790 Duke comes with a lot of gubbins (I mean, a lot); this is the unique selling point of this bike. Thanks to near MotoGP grade electronics, KTM's refined mechanical mastery and a perfect balance, the 790 has a lot of aces up it's sleeve. Let's see, shall we? - Bosch electronics (software and hardware). The 790's electronics package is through the roof. From four rider modes (rain, street, sport and track), to multi adjustable ABS, slip control and throttle sensors. Launch and anti-wheelie control, traction control and lean angle sensitive ABS too. The electronics package is worth a review on it's own. - WP front and rear suspension; fixed state on the front and simple adjustment at the rear. - Steering dampener. It's safe to say the 790 is well equipped, far more than it's peers within the market, which provides the bang for your buck characteristic that this bike really does have!

Great all rounder . Guess that why sport bike riders buy these . Tank bag on & you can easily tour . Lots of options like rear racks . Heated grips & the like to make it easier . Not pillion friendly but what bike is ? Unless you buy a barge tourer like bike. Fuel consumption good & easy 130 miles range & that long enough for me Bike can visit the shops.tour or do a fun track day .

Engine is a bit rattly but has lots of low down torque & can rev all the way to the red line with ease . Nice strong performance from a twin . Not silky smooth like a four but character is fun to use . As mentioned euro compliance means like all current bikes they run very lean . So part throttle & low speed can be a pain . Fitting powerboost plug or similar improves this aspect .

Not Japanese reliability or quality sorry to say so buy accordingly . Coolant hoses / clips leak . Thermostat housing area common fail Radiators can fail leak at seams . Oil leaks from poorly fitted joints . Sensors & wires not very well routed/ secured .ie . Abs wires rear . If Ktm spent 10 minutes more just tidying up & re-routing wires properly tightening then so much better . Engine like all new euro compliant bikes . Run rough at low speed /jerky . Powerboost plug or other resolves this issue .shame manufacturers cannot do this or offer option of better quality mapping . Not just track rain etc ! But legislation is what it is . Paint can scratch off underside of rear swing arm /chain route/adjustment is poor . Brake discs front warp (most done under warranty ) but be aware . Continuous ecu software updates via your Ktm dealer to resolve a few other issues . Failure of quick shift etc . Immobiler fitted as std & other electronics mean a healthy battery essential recommend optimate . Tyres std fit are not that good . Wear quickly so budget for replacing them with better quality .

Lot of cash for an oil. filter & mesh screens to be replaced . But Major svc interval & valve clearance costs mean I won’t be getting those done for a while .

All electronics are here . Quick shift. Led lights abs etc . Accessories heated grips . Seat pads . Touring racks all available. Tyres maxxis ok but wear quickly so budget for replacement. All major makes available just personal preference .

Suspension is firm but takes the edge off bumps. Perfect for all roads, with surprisingly low wind blast and noise on the motorway. Riding position and saddle are very comfortable and there is plenty of room to move around. I have done up to 200 miles and 3 hours without pain.

Good spread of grunt and power makes makes it delightful on twisty roads and effortless on the motorway, when 6th gear comes into its own with more than enough power on hand.

No problems. The parts seem well made and controls very nice. At first the quick shifter was harsh and the bike was jerky at low speed. Now at 1500 miles, both are smooth and easy.

70mpg running in and then 55-60 mpg. It has standard items which are extra on the 890. Since that arrived it has become even better value.

The metal tank allows a magnetic bag for popping down to the shops, and in spite of high exhaust outlet an expandable SW Motech bag goes fine on the pillion seat.

I gave it a 2 as the ride is great when it works. But the risk of it cutting out mid ride ruins it.

Cuts out while riding. Electronics fail.

Absolutely riddled with faults (see overview).

Once it is out of warranty, costs will be high, fixing all the faults.

Launch control doesn't work. Traction control warning light after only a year of ownership.

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.

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.

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/

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.

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.

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

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

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.

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.

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.

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

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 !

Not the most competent brakes and think it’s because I’ve been spoilt previously with Brembo set ups.

Brilliant!!!

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.

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.

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.