Rieju first to launch 2026 enduro models – fuel-injected two-strokes finally land, beating every other manufacturer to the punch by releasing their long-awaited fuel-injected two-strokes, the MR300i Pro and Racing versions.

It feels like we’ve been talking about this updated bike for some time now, with Enduro21 stories going back over a year. That’s mainly because the Spanish manufacturer has been developing the bike very much in public – and at the races.

It’s a risky strategy when things don’t quite go to plan, but it also builds anticipation. For a manufacturer with a presence in just about every major race championship, you could argue that all publicity is good publicity.

The result is a machine with some significant updates. Most notably, the in-house developed, throttle body fuel-injected 300cc two-stroke engine. But there’s more to note: a diaphragm clutch, three engine maps, counter-balancer shaft, 48mm KYB AOS forks and KYB rear shock. The 2026 Rieju MR300i – in both Racing and Pro editions – is not short on spec and should grab your attention if you’re in the market for a new enduro bike.

Bold claims

Reiju are also making some very big claims about the new MR PRO 300i, most of which we think is meant to encourage you and not put you off: A compact and “VERY agile bike with a “spectacular” turning radius. It is also, they say, a “beast” which “can move like a fish in water”. 

They continue: “It’s pure fun for riders who have the talent – and the guts – to push its engine to the limit. But beware, because it is unforgiving: this bike is pure breed, reactive like few others and created for those who are not afraid to come face to face with the intensity of true Hard Enduro.”

First class R&D

Developed over several years now with Alfredo Gomez notably taking the fuel injected bike to selected Hard Enduro World Championship races as part of the programme, Rieju’s new bike has showcased itself handsomely in the hands of Dominik Olszowy.

The Polish rider, who bases himself near the Rieju HQ in Figueres, near Girona in Northern Spain, has been a factory rider for a couple of seasons and has also been part of the R&D team developing this bike in that time. It’s a bike which he clearly gels with and ticked off SuperEnduro World Championship race wins and an EnduroGP Super Test fastest time just last weekend in Portugal.

The new Hard Enduro range (not just for hard enduro you understand, although it could be, but hard as in tough, we assume) consists of two models at present: Racing and Pro editions. So, no 250 model at present and only 2T bikes for enduro but who’s complaining?

MR PRO 300i technical highlights

The new MR PRO 300i houses a 300cc two-stroke single-cylinder engine with electronic injection, electronic exhaust valve developed and manufactured in Spain. It’s a bold and not inconsiderable investment of time and money to develop a TFI (Throttle body Fuel Injection) engine.

When Enduro21 spoke to Gomez about the development process he talked about how difficult it is but also how he was specifically employed because of his work with KTM previously developing their fuel injected engine.

“Precise and punchy power delivery” they say with two specific and differentiated Bosch injectors which moderate fuel consumption, deliver good performance and a contribute to a significant reduction in CO2 emissions “without sacrificing the immediate engine response and throttle feel characteristic of carburettor models”, Rieju add. 

The MR300 never lacked power with the carburettor so having three power mode options will help to adjust to different conditions.  “Race”, “Forest” and “Wet” riding modes adjust the power curve of the engine and adjust performance at different engine speeds.

Diaphragm clutch

Rieju say the new MR PRO has “taken a giant leap forward” with a Diaphragm Clutch, which replaces the traditional coil spring system of the previous version. Common on other manufacturer’s enduro bikes, the diaphragm system improves feel and is smoother and more precise when you’re modulating the lever while riding. 

Just as important we say is the addition of a counter-balance balance shaft that significantly reduces vibration and aids stability and confidence on the track and trail.

We take it from the press material we’ve got that the diaphragm clutch is only fitted to the Pro model, so not the Racing. 

No change in the chassis

In terms of the chassis, Rieju say the 2026 MR 300i “retains the essence of its predecessor: a chrome-molybdenum steel central chassis with an aluminium subframe.”

Not details changes are listed in the press material we have but we’ll endeavour to find out if the frame has seen any updates. 

First class suspension

A feature always of the modern generation Rieju enduro models is the KYB suspension. Rieju use 48mm KYB inverted fork with AOS (Air-Oil Separated) system and closed cartridge which is hard to better on a standard enduro bike in the market.

The Pro model goes one step further with black anodised DLC Antifriction Treatment on the forks which looks 10-times cooler but also claim less stiction.  

The KYB monoshock rear suspension is also fully adjustable in preload, rebound and high and low speed differentiated compression.

Impressive spec list

Part of the Rieju shtick has always been a decent price compared to other manufacturer’s to-stroke enduro models, plus the list of parts you get as standard.

Just over 100kg dry weight, 9.8 litre fuel tank, now with the Fi engine and three rider modes, ok, we got all that. But original equipment includes black anodised Excel aluminium rims, Mitas Terra Force tyres, Neken handlebars and grips, a crankcase protector, OXA exhaust system, X-Ring chain retainer, Nissin brakes and Galfer discs. 

The PRO model again goes a step further adding to the above with: black anodized DLC Antifriction Treatment on the forks, Renthal Fatbar handlebars and grips, Polisport Bullit handguards, X-Trig Rocs aluminium triple clamps, Excel rims with red machined wheel hubs and fitted with Michelin Enduro Medium tyres, and a two-tone non-slip seat.

No price or availability information at present but we’ll update. 

More information: www.rieju.com