The CRF250R’s bottom-end torque output gets a major boost; the engine also receives 3-level HRC Launch Control plus durability upgrades. A new front brake caliper, Renthal Fatbars – adjustable 4 ways – and black DID rims round out the updates.

Model updates: The CRF250R’s bottom-end torque output gets a major boost; the engine also receives 3-level HRC Launch Control plus durability upgrades. A new front brake caliper, Renthal Fatbars – adjustable 4 ways – and black DID rims round out the updates.

Contents:

1 Introduction

2 Model overview

3 Key features

4 Technical specifications

1. Introduction

Honda’s CRF250R has shown itself a worthy weapon for battle in the hard-fought MX2 class. And it is a machine that has evolved over time, through increments and steps, into a base platform that the amateur MX enthusiast – as well as pro-racer – can get the most out of.

For 18YM, the CRF250R made a giant leap forward, with a ground-up redesign that inherited the ‘Absolute Holeshot’philosophy of the 17YM CRF450R. Sharing its seventh-generation frame, revised geometry and Showa suspension – plus a brand new DOHC engine – the CRF250R proved its potential in the hands of Honda’s Factory racers.

Likewise, with its switchable engine mapping and rider-focused ergonomics it remained an MX machine that the hobby rider could exploit to their individual level of ability.

Resting on laurels is not an option in MX2, staying ahead of the pack becomes harder year by year; so for 19YM, one year on from a full model change, the CRF250R already receives updates to engine and chassis, further improving output, rider comfort and braking ability.

2. Model Overview

Focus at this stage of development for the CRF250R revolved around boosting the engine’s low-rpm torque to gain time out of slower corners; it’s been achieved with revisions from the throttle body all the way to the exhaust.

Durability has also been improved and 3-mode HRC Launch Control is an addition, that helps any rider – from beginner to expert – hit the mark straight out of the gate every time.

The frame and Showa suspension are unchanged, but a new front brake caliper improves performance, while Renthal Fatbars are now fitted at standard equipment. The DID rims also wear a new black finish.

3. Key Features

3.1 Engine

• Stronger bottom-end torque with no loss of top-end power
• Revised throttle body, cylinder head, intake and exhaust
• 3 level HRC Launch Control optimises start performance
• Durability improved with 5-hole piston oil jet

What was important for the Honda engineers developing the YM19 CRF250R was to maintain the engine’s stunning peak power output, and at the same time bolster it at the bottom of the rpm curve, for sharper jump out of slow-speed corners.

The task has been achieved with a number of upgrades, starting with a 2mm smaller (now 44mm) diameter throttle body, to speed up low-rpm air flow. The inlet and exhaust ports have been re-shaped and the exhaust valve cam ‘closing’ profile also reduced by 2°, all to boost torque. The righthand exhaust down pipe is 50mm shorter, to maintain top-end power. A decrease in output from the ACG generator reduces drag on the engine.

Bore and stroke remains 79 x 50.9mm, with a 4.5mm cylinder offset to reduce friction and compression ratio of 13.9:1. The valves are titanium; 33mm inlet and 26mm exhaust. Lift is 10.5mm inlet and 9.5mm exhaust and the valve angle is set at 20.5°. The valve springs themselves are oval in section; the inlet valves are fed by symmetrical straight-shot downdraft intakes, which are shorter for improved high rpm snap.

The piston is a Bridged Box design. Its rigidity converts combustion pressure into high output efficiency; for YM19 a 5-hole piston oil jet replaces the previous 4-hole design, improving piston cooling and optimising ignition timing.

A scavenge oil pump system reduces friction and ‘pumping’ losses at high rpm, by discharging oil and air in the crankcase and maintaining negative pressure. The oil also lubricates the clutch and gearbox, with a total oil capacity of 1.3 litres. The combined oil pump/drive gear, oil filter and oil way are on the right side of the engine – the oil’s path around the engine is short and straightforward.

Valve train lubrication is routed through the cylinder head to the inside of both inlet and exhaust cam, directly feeding the sliding surface of cam and rocker arm. The 5-speed gearbox drives through a 13T front and 48T rear sprocket.

The rider controls and displays – engine stop button, EFI warning, EMSB mode button and LED indicator – are rationalised together and sited on the left handlebar:

New for YM19 HRC’s Launch Control system gives any rider the best option for a strong start and has 3 modes to choose from:

Level 3 – 8,250rpm, muddy conditions/beginner

Level 2 – 8,500rpm, dry conditions/basic

Level 1 – 9,500rpm, dry conditions/expert

Activating HRC Launch Control is easy – to turn on, pull in the clutch and push the Start button (on the right). The LED will blink once for Level 1 selection. Push the Start button again, for .5s or longer, and the LED will blink twice for Level 2. Repeat the process and the LED will blink 3 times, indication Level 3 has been chosen.

The Engine Mode Select Button (EMSB) alters the engine’s characteristics and three maps are available to suit riding conditions or rider preference: Mode 1 (Standard), Mode 2 (Smooth) and Mode 3 (Aggressive). The LED also displays Mode selected.

3.2 Chassis

• New front brake caliper and hose improves stopping performance
• Renthal Fatbar now OE fitment, 4-way adjustable position
• DID wheel rims finished in black
• Sump guard and fork protectors redesigned

If the main focus of YM19 revolves around more bottom-end power from the engine, the CRF250R’s chassis has been updated to improve braking performance.

A new twin-piston front brake caliper – also common with the YM19 CRF450R – uses 30 and 27mm diameter pistons (the previous design used 2 x 27mm pistons). This allows for a lighter body and, along with low expansion rate brake hose, improves brake feel and staying power. It works on a 260mm wave-pattern disc, matched by a rear 240mm wave-pattern disc and single-piston caliper.

The Renthal Fatbar reduces the weight of the steering system and flexes for optimal comfort; the top yoke features two handlebar-holder locations for moving the handlebar rearward and forward by 26mm. When the holder is turned 180 degrees, the handlebar can be moved an additional 10mm from the base position, resulting in four total unique riding positions.

Rake and trail are set at 27.5°/116mm, with wheelbase of 1486mm. Wet weight is 108kg. The fully adjustable 49mm Showa USD coil spring fork is a version of the Showa ‘factory’ fork supplied to MX race teams in the Japanese championship; the cylinder has a 25mm diameter, the rod 14mm and the compression piston 39mm. The Showa rear shock is also fully adjustable.

Lightweight DID aluminium rims, with directly attached spoke pattern layout are now finished in black; the front is a 21 x 1.6in, the rear a 19 x 1.85in. Fitted as standard equipment are Dunlop’s GEOMAX MX3S tyres, 80/100-21 front and 100/90-19 rear.

The CRF250R uses a lightweight 6.3L titanium fuel tank. Its smooth external lines of the plastics help the rider move easily, and the narrow frontal area and front mudguard directs an efficient funnel of air to the radiator.

The bodywork uses durable film inset graphics that cover a wide area with scratch-resistant style; the engine sump guard has been redesigned to improve engine cooling and fork protector modified to reduce chance of stone damage.

4. Technical Specifications

All specifications are provisional and subject to change without notice.