2025 Suzuki DR-Z4SM Review

There are very few motorcycles that make me laugh quite as much as a supermoto. This most underrated form of riding has been forgotten by all but two mainstream manufacturers. However, thank god, Suzuki has the courage to put a factory-built 17-inch-wheel dirt bike on the street for us to buy, rather than requiring us to convert a dirt bike ourselves and suffer the pitfalls of our own shoddy workmanship.

Photography by Kevin Wing

Suzuki has been in this street supermoto game for an impressive 20 years, with the DR-Z400SM beginning life way back in 2005. In that time, the model has seen gradual updates, but it hasn’t received a full makeover until 2025 as it moves lockstep with the DR-Z4S dual sport our editor Kit Palmer tested at the world launch  in Oregon back in June of this year.

To make a (very) long story a little shorter, the $8999 2025 4SM shares about 90 percent of the upgrades the Z4S came to the market with earlier this year. Suzuki is claiming 37.5 horsepower at 8000 rpm and 27.9 lb‑ft at 6500 rpm from the 398cc single-cylinder motor, which is slightly less than the outgoing model that wasn’t Euro5 compliant.

The engine receives a new intake, cylinder head, cam profile, titanium intake valves, sodium‑filled exhaust valves, dual iridium spark plugs, a new piston, crankcase that no longer needs the kickstart bosses and hole, and it’s all fed through a 42mm throttle body with the mixture sparking off a 10‑hole injector.

Increased low-down torque was the aim of the game with the new 4SM, making it a more rideable proposition for general street riding and traffic-light GPs. Interestingly, Suzuki claims the new motor has a reduction of mechanical losses by 20 percent at 8000 rpm, which shouldn’t be too hard to achieve given the previous motor can trace its heritage back to 2005.

Die-hard fans of the DR-Z range have been howling for a sixth gear for a long time, but Suzuki decided against it, citing weight and manufacturing-cost concerns.

As such, the engine’s go is transmitted to the tire using the same five-speed transmission as before, and this proved to be one of the bike’s major flaws when we conducted freeway riding, or any riding north of 60 mph for that matter, as the revs felt too high, and a lack of top-end acceleration hurt the SM’s potential. Oh, and we can’t even tell you what revs we were doing at 60 mph, because there’s no rev counter on the 4SM’s dash.

Suzuki has tried to reduce the impact of not having a sixth gear by giving the 4SM a smaller rear sprocket for taller gearing (41 teeth compared to the 4S’s 43 teeth, although both use the same 15-tooth front sprocket), but the lack of a sixth gear is still a glaring omission from Suzuki’s engineers.

As for the clutch, it is now a slip-and-assist type that uses Suzuki’s Clutch Assist System (SCAS) for a light lever pull. Performance junkies will note there’s no quickshifter, nor the option of upgrading to one in Suzuki’s aftermarket catalog.

Regardless of the missing quickshifter, the 4SM still gets a big upgrade in the electronics department with the fitment of the Suzuki Intelligent Ride System (S.I.R.S.). This includes the Suzuki Drive Mode Selector (SDMS) and the Suzuki Traction Control System (STCS), which features the same G (Gravel) mode as on the 4S but with a different level of slip (i.e., more electronic intervention). And, like the orange archrivals from Austria, the 4S now has ABS that can be turned off on the rear, but being a street model, it is always engaged on the front wheel.

The bones of the 4SM have also been drastically altered. Gone is the steel tube single cradle frame; in its place sits an all-new, twin-spar steel design with the engine’s oil now in the frame.

Suzuki is claiming a 9.3 percent increase in torsional rigidity with the new chassis, with suspension now inverted 46mm KYB forks up front (adjustable for compression and rebound) and a fully adjustable KYB monoshock out back. Wheel travel has gone up 0.8 inches up front and 0.7 inches at the rear.

Braking hasn’t changed, with the Nissin twin-piston caliper gripping a 310mm disc up front and a single-piston caliper stopping a 240mm piston at the rear. And although the wheels haven’t changed, Suzuki has fitted the 4SM with Dunlop’s Sportmax Q5A rubber.

Ride Impression

A supermoto between traffic lights is one of motorcycling’s great joys, and here the 4SM delivers beautifully. The 4SM is perfectly designed as an inner-city zip-around bike and one that will happily carve your local twisty with the best of them—and if you keep your riding to those areas, the 4SM is hard to fault.

Baseline suspension settings are extremely soft, and if you want to get out there for a rip, you’ll definitely want to jack up the rear preload and stiffen the fork. The good news is that the 4SM responds to a few clicks on the clickers here and there, which bodes well for the overall quality of the KYB suspenders.

The 4SM is very light on its feet thanks to the surprisingly competent Dunlop Sportmax Q5A. Compared to the Michelin units found on the KTM 390 SMC R, the Dunlops have a more tactile feel thanks to being slightly softer in their carcass. All this means it’s easier to feel what the Suzuki is doing underneath you.

The chassis is light and agile, allowing you to pick and choose your line with the same ease as a minimoto, not a supermoto. This is the appeal of a bike such as this: it’s incredibly easy to use and use well. It won’t scare you and offers enough performance that riders of almost any skill level can enjoy.

One could argue you don’t need adjustable riding modes on the 4SM, and that person would be dead right. They are completely superfluous needs on a sub-40 hp motorcycle, but having the adjustable traction control and switchable ABS is a good feature.

The 398cc motor’s increased low-down torque is noticeable on the street; cruising from stop sign to stop sign is a little less urgent compared to the previous iteration, so it gives you a more relaxing ride in this instance.

However, a lack of sixth gear is a major problem given how buzzy the motor becomes at freeway speeds. No amount of gearing change is going to make up for this, and given KTM has a sixth gear on their 390 SMC R, Suzuki will want to rectify this in the near future.

The lack of a sixth gear also hurts the motor on the racetrack, as it begins to run out of steam a little too early for my liking. Overall, the gear ratios themselves are nicely spaced—there’s just not enough of them.

Another area of concern is the discomfort of that seat. Yes, I know it’s a dirt bike seat and all, but my god, it is seriously painful after an hour on board. This further leads the bike toward short, sharp journeys where there are a few wheelies and back-ins to be had—and for that, few match the 4SM for outright laughs.

However, the big elephant in the room is, you guessed it, the price. At $8999, that is a massive difference over its nearest rival in the KTM 390 SMC R, a machine that has a lot more features for $5499, including a TFT dash that has phone connectivity and can therefore give turn-by-turn navigation, a 12V USB-C socket (this can be added in Suzuki’s aftermarket catalog) and—a sixth gear. I know we’re not comparing the two directly in this article, but potential buyers certainly will be, so I guess a head-to-head test is in order.

What the Suzuki has on its side is its rock-solid build-quality reputation, with the whole bike being made in Japan at the Hamamatsu factory. These are similar to Honda’s XR in that you can’t kill them with a brick, and they are a legacy built over decades.

I personally feel the 4SM is about $1000 too much, given what you get, but I am not involved in any of Suzuki’s marketing and pricing. However, there’s a good chance this 4SM will be the one left standing in another 20 years’ time thanks to that famous reliability.

Regardless, it is great to see Suzuki has kept the supermoto faith all these years. Time to go for another skid.CN

VIDEO | 2025 Suzuki DR-Z4SM First Ride Review

 

2025 Suzuki DR-Z4SM Specifications

Click here to read the 2025 Suzuki DR-Z4SM Review in the Cycle News Digital Edition Magazine.

 

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