The ROTWILD R.X735 ULTRA – In our huge “Best e-mountainbike of 2023” group test

Despite using a powerful Shimano EP8 motor and big 720 Wh battery, the ROTWILD R.X735 is still one of the lightest bikes in its category at only 21,2 kg. The Swiss deer combines 150/144 mm of travel, front and rear, and retails at € 12,499. How does it compare to the competition?

**ROTWILD** R.X735 ULTRA | Shimano EP8/720 Wh | 150/144 mm (f/r)
21.2 kg in size L | € 12,499 | Manufacturer’s website

On their website, ROTWILD divide their bikes into two categories, called the EXTENSIVE and AGGRESSIVE Series. Designed to be the ultimate trail machine, the R.X735 falls into the latter category, which focuses on maximum efficiency, agility and intuitive handling. According to the Swiss manufacturer, the R.X735 is aimed primarily at sporty riders who want to feel the tiniest feedback from the ground. In ROTWILD’s portfolio, the R.X735 sits right in between the R.X375 with its small 375 Wh battery and the powerful R.X750 ULTRA from the EXTENSIVE Series – yep, that’s a hell of a numeric anagram! With its angular silhouette and bright-red finish with black and golden accents, the R.X735 ULTRA is distinctly recognisable as a ROTWILD. The square edged carbon frame relies on an aggressive design language, which suits the trail-heavy application range of the bike extremely well.

For an overview of the test fleet head to the group test: The best eMTB of 2023 – 30 models in review

When you’re in a hurry – what sets the ROTWILD R.X735 ULTRA apart from the competition?

At the heart of the R.X735 ULTRA lies a powerful, 85 Nm Shimano EP8 motor, which is beautifully integrated into the frame and provides unintrusive assistance – except for the distinctive metallic clunking noise of the EP8 clutch. The 720 Wh battery can be easily removed from the side of the frame using a quick-release button, which proved the quickest and most intuitive battery removal system in the entire test field. If you tend to leave your bike parked outside, you can replace the quick-release system with a bolt lock – or just take the battery with you. The charging port sits just below the battery on the side of the down tube, where it’s easy to access. A magnetic rubber cover protects it from grit and mud, but this isn’t secured to the frame, making it easy to misplace while charging. However, the magnetic system comes in handy, allowing you to attach the cover to the FIDLOCK bottle cage while charging. A Shimano SC-EM800 display shows the battery charge status and current support mode, and the data cables are neatly tucked away under the handlebars.

**Ready, steady, go!**
The battery can be easily removed from the side of the frame without tools. Overall, ROTWILD’s quick-release system is the most intuitive and quickest to use in the entire test field.

**Beautifully integrated**
The 720 Wh battery is combined with a powerful, 85 Nm Shimano EP8 motor, which is seamlessly integrated into the frame.

**Not all that glitters is gold**
The fancy Kashima coating blends in nicely with the overall look of the ROTWILD. Unfortunately, the FOX 36 Factory fork relies on the cheaper FIT4 damper, which is less sensitive than its superior GRIP2 counterpart.

The FOX Factory suspension controls 150/144 mm of travel, at the front and rear, and makes a very high-quality impression with its fancy Kashima coating. Upon closer inspection, however, the fork employs a FIT4 damper, which is less sensitive and adjustable than its superior GRIP2 counterpart – a real bummer, especially for sporty riders! Another thorn in the side are the Schwalbe tires. We recommend replacing at least the front tire with the more robust version in the tougher Super Trail casing and softer Ultra Soft rubber compound, to generate more traction and protect the expensive carbon rims from nasty impacts. On the other hand, we’re really fond of the 210 mm EightPins NGS 2 dropper post, which lets you adjust the travel using a dial on the saddle clamp head. Unlike most conventional dropper posts, which use oil as a holding or adjusting medium, the EightPins relies on pure mechanics, locking the post tube in 6 mm intervals rather than infinitely. Shimano XTR four-piston brakes with 203 mm rotors do stopping duties while a matching XTR drivetrain ensures crisp, smooth shifting. The shifter and remote mount directly to the brake levers using Shimano’s i-Spec system, keeping the ROTWILD’s in-house handlebars nice and tidy.

**Lift**
Unlike most conventional dropper posts, the 210 mm EightPins NGS 2 relies on pure mechanics.

**Don’t lose it!**
The charging port is easy to access and protected by a magnetic rubber cover. However, the latter isn’t secured to the frame, which makes it easy to lose when charging. Here the magnetic system comes in handy, allowing you to secure the cover on the FIDLOCK bottle cage, which also uses a magnet.

ROTWILD R.X735 ULTRA

€ 12,499

Specifications

Motor Shimano EP8 85 Nm
Battery IPU735 QR Carbon 720 Wh
Display Shimano SC-EM800
Fork FOX 36 Factory FIT4 150 mm
Rear Shock FOX FLOAT X Factory 144 mm
Seatpost EightPins NGS 2.0 210 mm
Brakes Shimano XTR 200/200 mm
Drivetrain Shimano XTR 1x12
Stem ROTWILD S140 50 mm
Handlebar ROTWILD B220 Carbon 780 mm
Wheelset Crankbrothers Synthesis Enduro I9 Carbon 29"
Tires Schwalbe Magic Mary Super Ground Soft /Schwalbe Hans Dampf Evo Super Trail Soft 2.4/2.4

Technical Data

Size S M L XL
Weight 21.2 kg
Perm. total weight 130 kg
Max. payload (rider/equipment) 108 kg
Trailer approval no
Kickstand mount no

Specific Features

FIDLOCK bottle holder
Quickrelease function

Tuning tips: Handlebars with more rise to lift the front | Tires with softer rubber compound and tougher casing like Schwalbe’s Magic Mary Super Trail Ultra Soft

Like a young buck – what is the ROTWILD R.X735 ULTRA capable of on the trail?

The ROTWILD R.X735 ULTRA is like a young buck romping through the forest with its mates. With its lively character and supportive suspension, it constantly encourages you to pop off ledges and scan the trail for alternative lines. In flat, flowing trail sections, it allows you to generate tons of speed by pumping through rollers. On steep descents, the low front end requires good riding skills to keep the deer in check. The ROTWILD is more nimble than composed, encouraging you to be creative with your line choice rather than ploughing your way back down into the valley in a straight line. Moreover, the insensitive fork and hard rubber compound at the front cost traction, making it hard to control the ROTWILD in open corners.

**Physical**
On steep ramps, the ROTWILD requires a great deal of physical effort to keep the front wheel tracking.

**As nimble as a young buck**
The ROTWILD feels at home on moderate flow-trails, where it allows you to generate lots of speed by pumping through rollers.

In zoological terms, the ROTWILD combines the lively character of a young buck and the stamina of a fully grown stag. The big battery provides enough power for epic backcountry adventures but, unfortunately, the stretched riding position messes with your lumbar discs a little. While the agile handling makes it easy to negotiate technical climbs with tight corners, on steeper uphill sections you’ll have to actively weight the front wheel to keep it tracking. On smooth fire roads, the firm, efficient suspension allows you to glide along in relaxed fashion, but the powerful motor struggles to keep up with Bosch and Polini equipped beasts.

The agile handling allows you to throw the ROTWILD R.X735 ULTRA from corner to corner.

Size	S	M	L	XL
Top tube	597 mm	617 mm	647 mm	675 mm
Seat tube	410 mm	440 mm	470 mm	506 mm
Head tube	110 mm	110 mm	130 mm	140 mm
Head angle	65.5°	65.5°	65.5°	65.5°
Seat angle	75°	75°	75°	75°
Chainstay	450 mm	450 mm	450 mm	450 mm
BB Drop	30 mm	30 mm	30 mm	30 mm
Wheelbase	1,200 mm	1,219 mm	1,253 mm	1,282 mm
Reach	430 mm	450 mm	475 mm	500 mm
Stack	625 mm	625 mm	643 mm	652 mm

**Helmet** SCOTT Stego | **Glasses** SCOTT Shield | **Hip Pack** Canyon Hip Bag | **Jacket** GORE BIKE WEAR Spirit vest | **Shorts** HIRU Lab | **Kneepad** ION K-Pact Zip | **Shoes** Five Ten Hellcat Pro | **Socks** HIRU Merino

Who should take a closer look at the ROTWILD R.X735 ULTRA and who should look elsewhere?

The ROTWILD R.X735 ULTRA is an exciting option especially for sporty flow riders, provided they have the skills to tame the lively handling, especially on techy singletrack. The ROTWILD R.X735 ULTRA is also suited for tourers who want a powerful motor and big range, assuming they get along with the stretched riding position.

On moderate flow-trails, the ROTWILD R.X735 ULTRA allows you to generate lots of speed by pumping through rollers

Riding Characteristics

DESIGN

unbalanced
coherent

USER FRIENDLINESS

cumbersome
clever

VALUE FOR MONEY

flop
top

TREKKING & COMMUTING SUITABILITY

low
high

HANDLING

demanding
intuitive

FUN FACTOR

boring
lively

Intended Use

Gravel roads

Technical climbs

Flowtrail descents

Technical descents

Conclusions about the ROTWILD R.X735 ULTRA

The ROTWILD R.X735 ULTRA convinces with a discreet look and clever detail solutions, including the battery’s intuitive quick release system. Experienced riders will love the agile handling, especially on flow trails, but on technical trails, the deer is held back by its own spec. Moreover, the ROTWILD is only conditionally suitable for beginners and tourers. Despite ROTWILD’s bold claims, we cannot crown the R.X735 ULTRA as the ultimate trail king, because there are bikes in this test that are far better all-rounders.

Tops

Most intuitive battery release system
Excellent system integration
Agile handling on moderate flow-trails

Flops

Tires and fork don’t do justice to the bike’s potential

You can find out more about at rotwild.com

The test field