X-90 Mountain Frame

X90 Custom Folding Bike Frame
Original price was: 539,00€.Current price is: 499,00€Seen it for less?.

Prices include VAT in Germany. Depending on the delivery address, the VAT at the checkout may vary.

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Mountain Frame

A race-ready hard tail. Ready to accept front suspension, hydraulic disc brakes, and 26″ or 27.5″ wheels. Fork not included.

The essentials

• Supports 10 or 11 speed cassettes
• Wheel size: 26″ oder 27,5″
• Time to fold: 20s
• Folded size: 92cm x 72cm x 31cm
• Weight: ca. 2.65 kg

Great for

• Race day
• Epic mountain rides
• Fast single track
• Technical cross country

Frame sizes

• 45 cm Frame: For riders 160-178 cm
Standover height is 76 cm
• 50 cm Frame: For riders above 179 cm
Standover height is 79 cm


The Montague SwissBike X90 Custom is an aggressive folding hardtail with a stiff frame providing both performance and portability. This frame supports 26” or 27.5″ wheels; it’s a full-size bike with full-size performance, but folds to fit in the trunk of a car or in a small closet. These rugged folding bikes are built to outlast, handle any terrain, and carry a ton of gear.

X90 Custom Folding Frame Folded

Independent Review

“The more I rode this bike the more I began to enjoy myself. The tyres handled the conditions confidently, subject to the usual rules of staying off wet roots, not pushing your luck on greasy timber boardwalks, and avoiding the mud wherever possible.

At speed, the descending was stable and confident. The narrow bars compensated somewhat for the relaxed geometry so the bike was far more flickable than expected from the slack steering angle. It also meant fitting into the gaps between the trees and bridge handrails was easier. The short top tube was actually an asset when the trail pointed down, giving the bike great technical descending ability over the tricky roll-downs on my local trail. The Montague really seemed to carve on the turns, and the bike felt really sound, firm, and well planted. At no time did I notice that I was riding a “folding” bike – it seemed every bit as solid as my regular hardtail.

Braking was excellent, requiring only the index finger to pull up my 90kg riding weight with ease. Shifting was reliable and smooth despite being sprayed with mud and wet Sydney sand for the entire duration of test riding. The wheels felt strong and stiff, easily handling the beating I gave them over rough rock gardens despite the relatively low volume rubber. The suspension seat post was welcome on these trail sections! Folding this bike and reassembling it is really simple, and folding can be completed in about 20 seconds, less with practice. A neat nylon carry bag is available, and it has a separate pocket for the front wheel to avoid rubbing on the paint.

This bike is no toy. It has many admirable qualities, not least of which is its confident descending ability. With wider handlebars it will be an excellent all round hardtail. It easily folds up and is opened out again just as quickly. It is refreshing to find a full-size bike with this capability, negating the need to make the handling, performance and safety sacrifices normally associated with smaller wheels. Overall, I was pleasantly surprised by the Montague – it certainly exceeded my expectations.”

John Hawkins

Bicycle Network Australia

X90 Folding Bike Frame System Closeup

CLIX Folding System

Clever integration of the patented CLIX System allows for the Paratrooper Pro to be folded in under 20 seconds without the use of tools. A flip of the CLIX quick release lever on the top tube and the bike folds to a compact size.

Folding Integrated Technology

Each bike frame is built around our patented FIT system. This design eliminates the need to break the frame in order to fold the bike. Not only does this make folding easier, but it makes our bikes the strongest folding bikes on the market. Unlike other folding bicycles, you will not sacrifice performance for folding.
X90 Frame Folding System Closeup


Color Black and blue front frame.  Black rear frame.
Material Custom drawn 7005 Series Aluminum tubing with FIT System.Disc mount and removable rear derailleur hanger.
Sizes 18″, 20”
Bottom Bracket 68mm English Threaded
Seat Post Diameter 30.0mm
Head Tube Diameter 1-1/8″
Fork Not included
Rear Frame O.L.D. Spacing 135mm. Vertical dropouts.
Drive Train Compatible with 10 or 11 speed cassettes.


Find a store to buy your new Montague folding bike.