Off road racing and Yamaha have been - and always will be - inseparable. Yamaha factory riders underlined the technical supremacy of the company's 'reverse head' YZ-F models in 2015 by winning the MXGP World Championship, as well as the prestigious MXGP Manufacturer's Championship.
Innovative Forward Thinking philosophy has made Yamaha one of the most dynamic and successful brands in the off road world and for 2017, the comprehensive range off motocross and enduro models bring factory performance within the reach of every off road rider.
For the 2017 season, Yamaha Motor is proud to introduce the new off road competition line-up with the higher performance 2017 YZ250F and detail changes to the other YZ-F, YZ and WR-F models.
Fine-tuning the YZ's winning DNA
Featuring an innovative reverse cylinder head engine, the groundbreaking Yamaha YZ250F has demonstrated it has got what it takes to outperform the toughest opposition. This game-changing motocross bike powered Jeremy Martin to consecutive AMA 250 Motocross Championships in 2014 and 2015, while YZ250F rider Cooper Webb has also taken consecutive AMA 250SX West titles in 2015 and 2016.
2017 YZ250F: Stronger, quicker, smoother
For the 2017 model year the YZ250F benefits from a range of important technical changes - such as an all-new reverse cylinder head - that are aimed at delivering increased performance and enhanced rideability.
2017 YZ250F improvements
With major enhancements to the intake and exhaust efficiency, together with a slicker shifting transmission and remapped ECU, the 2017-specification engine delivers a significant increase in race-winning performance.
All-new higher performance cylinder head
With its front facing inlet and rear exiting exhaust, the YZ250F's innovative reverse cylinder head offers many advantages over a conventional design. These include increased intake and exhaust efficiency, as well as enhanced mass centralisation thanks to the use of a top-mounted air filter and underseat fuel tank. For the 2017 model year Yamaha's engineers have taken this cutting-edge technology to the next level and developed a new reverse cylinder head that gives the YZ250F rider even stronger mid to high rpm pulling power.
Raised intake port and high lift camshafts
For an increased flow of fresh air into the 4-valve head, the intake port's position is raised and the intake valve diameter is increased. New higher lift intake and exhaust camshafts give increased valve lift for a stronger feeling in the mid to high rpm range - while for enhanced low to mid-range performance the intake camshaft's working angle has been narrowed.
Stronger valve springs and new con rod
Stronger intake and exhaust valve springs are fitted to correspond with the use of new higher lift camshafts - and to accommodate the increased engine performance, a newly designed nickel-chromium-molybdenum steel con rod is used for the 2017 model.
Shorter intake funnel and new throttle joint
Further significant power increases in the mid to high-rpm range have been achieved by shortening the intake funnel to achieve reduced pumping losses - and the use of a larger throttle joint between the injector and intake port gives an increased cross-sectional area of around 5% - while its new internal design promotes better fuel vaporisation.
Redesigned exhaust port and new big bore front pipe
To achieve an optimal intake/exhaust balance, the twin exhaust ports have been redesigned and the snaking exhaust header pipe is equipped with a new larger diameter front section. As well as featuring a bigger bore pipe, this front section also benefits from larger radius bends, giving a greater internal cross sectional area that creates a much stronger exhaust pulse effect.
New remapped ECU
To match the increased engine performance produced by the redesigned cylinder head and high efficiency intake and exhaust systems, the 2017 YZ250F is equipped with a newly developed ECU with revised ignition timing and fuel injector mapping. The new ECU cuts in at higher rpm and features a rev limiter that gives an improved over-rev feeling.
Yamaha Power Tuner
Riders of all abilities can also use the optional Yamaha Power Tuner to adjust the YZ250F's power characteristics. This compact device plugs straight into the bike without the need for a PC and enables the rider or mechanic to fine-tune the engine performance in seconds to suit the track conditions.
High strength crankcases
In order to handle the uprated engine's increased performance, the YZ250F is equipped with modified high-strength crankcases. While their exterior shape and construction is identical to the 2016 model, the aluminium die-cast cases on the 2017 model have been subjected to a heat treatment process that increases strength by around 5% for a high level of reliability and durability.
Smoother shifting transmission
To match the higher-powered engine's increased driving force, the 2017 YZ250F is equipped with a new transmission featuring wider teeth on the 2nd and 3rd drive gears.
The shape of the dogs on 1st, 3rd and 5th gears has also been modified and these changes - together with a redesigned shift cam and modifications to the clutch push lever and axle design - give smoother and quicker gear shifting. Finally, a more rigid gear shift lever gives a more positive shift feeling.
YZ250F Main Engine Changes
New high efficiency cylinder head
Revised intake and exhaust port shape
Larger intake valves
Higher lift intake and exhaust camshafts
New valve spring design
Newly designed con rod
Revised throttle joint
Modified air cleaner joint design
New big bore front exhaust
New ECU with revised map and rev limiter settings
High strength crankcases
Redesigned clutch push lever
Reshaped shift cam
Newly designed shift pedal
Made possible by the use of the reverse head engine, the YZ250F's top-mounted airbox and underseat fuel tank help to centralise mass for agile and responsive handling. The chassis changes introduced for 2017 include a revised balance of frame rigidity, together with a lower centre of gravity and refined suspension.
Fine-tuned aluminium beam frame
Using feedback from our factory teams, Yamaha have been able to fine-tune the frame in order to ensure that YZ250F riders are able to fully exploit the increased engine performance of the uprated 2017 model. Compared to the 2016 design, the 2017 frame is around 12mm wider in the area behind the swing-arm pivot point and this increased torsional rigidity ensures a higher degree of handling stability.
Steel engine mounting brackets
The YZ250F features specially designed front and upper engine mounting brackets that have been developed to complement the characteristics of the free-revving 250cc engine. By using 8mm thick steel for the two front brackets, with 6mm thick steel used for the upper brackets, the YZ250F's new frame delivers a better overall rigidity balance for improved handling performance and rideability.
To achieve a roomier riding position that best suits a wide range of racers, the footrest position on the 2017 YZ250F has been lowered by 5mm. This also helps to lower the centre of gravity to give increased control in ruts and corners.
Optimized suspension settings
Increased rideability and comfort have been achieved on the 2017 YZ250F through a number of revisions to the front and rear suspension. The class-leading Air Oil Separate (AOS) KYB® front forks feature a new more rigid outer tube design and slightly reduced oil capacity and these changes - together with new factory suspension settings - give improved rider feedback for improved chassis performance and stability in ruts, bumps and corners.
New material rear disc
For improved brake feel, the 245mm rear disc is manufactured using the same heat resistant steel as the 270mm front disc, giving total braking confidence on the fastest tracks.
Keeping the cool black rims, the 2017 model features new graphics on the shrouds and fenders, giving a professional factory look
YZ250F Main Chassis Changes
Refined aluminium bilateral beam frame
Newly designed high-rigidity fork outer tubes
Revised suspension settings
New rear disc material
New shroud and fender graphics
Availability: July 2016
With its MXGP World Championship winning performance, the Yamaha YZ450F is recognised as one of the leading 450cc motocross models. Featuring Yamaha's technologically advanced reverse cylinder head design, this revolutionary dirt bike gives every rider the chance to experience factory bike performance.
For 2017 the YZ450F features new graphics on the shrouds and fenders and the 245mm rear disc is manufactured from the same heat resistant steel as the 270mm front disc, giving improved braking feel and performance.
With their lightweight handling and instant hit of power, the YZ250 and YZ125 2-strokes underline Yamaha's total commitment to all dirt bike riders. Loved by 2-stroke fans for their ease of maintenance and unique character, these thoroughbreds come equipped with a larger 270mm front disc brake and feature new graphics on the shrouds and fenders for 2017.
Along with its bigger brothers, the YZ85 is one of the best-loved dirt bikes ever built, and many of today's champions began their careers with this legendary Yamaha. For 2017 the YZ85 is equipped with new graphics.
Featuring the same innovative reverse cylinder head engine layout and compact aluminium chassis design as the winning YZ-F models, the WR250F and WR450F have re-established Yamaha as a significant force in the enduro world.
With a full scale assault on the 2016 E2 and E1 World Championships, Yamaha is seriously committed to enduro and following a double E1 podium result in the first two Enduro GPs of 2016 - and a victory in the E2 class - Yamaha WR-F models are aiming high.
For 2017 the WR250F comes with a larger 270mm front disc brake and both the WR250F and WR450F feature new graphics on the shrouds and fenders for a professional factory look.
For 2017, Yamaha off road dealers will be able to supply competition riders with a wide range of GYTR (Genuine Yamaha Technology Racing) parts for the YZ450F, YZ250F and YZ125 models.
Individual GYTR performance parts will be available for the YZ450F and YZ250F, while YZ125 riders can order a dedicated GYTR YZ125 kit for their bike containing all the necessary parts required to achieve optimum performance.
Open to ambitious motocross riders born between 2000 and 2004, the Yamaha YZ125 Cup will be held during 2016. Aimed at introducing future champions to the world of international motocross, the YZ125 Cup will be run at a national level, with up to 42 riders competing in 13 countries in their domestic 125cc championships, with the top riders qualifying for the Superfinal in Germany on October 8th 2016.
The top 6 riders in the Superfinal - plus 2 wildcards - will be invited to join 2008 MX1 World Champion David Philippaerts for a multiple-day Masterclass and by the end of this training session, one rider will be chosen to become the official Yamaha factory rider in the EMX125 class for 2017!
Full information of riders, venues and dates at: www.yamaha-racing.com/yz125-cup/about
During 2016 the Yamaha MX Pro Tour will be visiting various tracks throughout Europe and customers will be able to test a range of Yamaha YZ-F and YZ models. Full details will be made available on the national distributor's website.
Yamaha have developed a range of off road riding gear, including riding jersey, trousers and gloves. The full 2017 line up will be available later in 2016. Details can be seen at www.yamaha-motor.eu/uk