With the production bike at such a high level of performance, refining a bike for race conditions is more a matter of personalising it to the rider rather than making wholesale changes.The first bike to take a closer look at will be the YZ250F of Levi Rogers. Rogers will make his debut in the MXD class for 2020 after progressing through the Yamaha Junior Racing program. The majority of his junior racing saw Rogers on basically standard bikes and things won’t change a lot for the 2020 season as he learns more about racing and his needs from the bike.
Starting from the Top
Rogers is a man child. Despite just turning 17, he is over 180cm tall and weighs in at 80kilos so a lot of the ergonomic changes made to his bike are to suit his tall frame. He uses Pro Taper SX High bend handlebars with Pro Taper diamond pattern grips. They are mounted on stock triple clamps with the mounts in the forward / forward position, again to give him more room.
The team use standard levers and controls that are greased and lubes regularly to keep them light and airy. He also favours a gripper seat cover to help stay in position on the bike. Since the inception of the 2019 model, the sub frame and general chassis remains standard.
The 2020 motor on the YZ250F is a great starting point. In fact, since the reverse cylinder was introduced to the YZ250F in 2014, it has been a class leader as far as power placement and output is concerned and has the championship success around the world to prove it.
The head is flowed by Kevin Marshall. Kev is the brains behind the Yamaha Road Racing team bikes and has years of experience both in the road and off road field. He does each head by hand after hours of studying them and working out the angles he needs for the style of power requested. Kev is never about the peak number, he is about rideability and his attention to detail is second to none. The standard cams and standard piston are used with no modifications.
A Rush O2 airfilter is used for better air flow as clean air to the YZ250F motor produces more power. Add to that an Akrapovic exhaust, some ETS MA-3 100 fuel and some mapping via the OEM Yamaha power tuner app and you have all the performance gains you need. GYTR engine covers are fitted to the clutch and the ignition side of the bike for that factory bike look. The final piece of the puzzle is the gearing where Rogers bounces between 13-49 or 13-50 depending on the track.
Levi has worked with Michael Marty of Brisbane Dirt Bike services in recent times and instead of just wasting that relationship, Rogers has continued with Michael and has fine-tuned his suspension to his needs. The valving has been altered, as has the spring rates and oil heights. The forks are coated and use SFK fork seals to reduce as much stiction and increase a smoother action.
Working off a static ride height of around 35mm and a rider sag of 105mm, Marty changes the spring to suit on the rear and then tunes the front similarly to ensure balance remains in the bike and the basic geometry is right.
Odds and Ends
Rogers is a huge fan of the Dunlop MX33 and uses it almost everywhere apart from the sandy based tracks where he might match the MX33 front with the paddle like MX12 rear. Wheels are mounted to OEM hubs, spokes and rims apart from supercross, where are stronger Excel rim is used to handle the big impacts. He also adjusting to running mousse tubes for the first time in his career as flat tyres often don’t lead to championship success.
The team add a second starter button and position it on the frame to be used as a back up in case of a crash. Learning from experience, a crash can often damage what’s mounted to the handlebars, including the start button, so a spare is made and mounted to the frame.
A GYTR holeshot button is on the bike and apart from a concrete start, you wouldn’t race without one. Most mounts come with a template for heights starting at 65, 85 and 100mm but most riders now go lower than that and often the start button height is anywhere between 115 and 145mm down the fork guard.
Yamalube oils and lubes are ran throughout the bike, from RS4GP in the motor to S1 Suspension fluid in the fork.
The last remaining bits to be added is a skid plate, that the team use from the FX model, as well as the clean and corporate looking sticker kit from Serco.
“This bike runs so good,” Rogers commented on the day he rode it first. “It is much more powerful than any of the bikes I had raced in juniors and power just continues to build from really low in the rpm. I love how it runs and didn’t want to get off it.
“And, the best thing about being with a team like Yamalube Yamaha is the bike will feel and look just as good at round ten as it will at round one and I’m excited to race it when round one finally comes around,” Rogers ends.
Spec Check- Levi Rogers YZ250F – #44
Mechanic – Nash Ilhe
Cylinder head: OEM with YRD flow
Throttle body: OEM
ECU: Yamaha Power Tuner – mapped to suit engine mods
Airfilter: Rush o2
Fuel: ETS MA-3 100
Engine Covers: GYTR
Chassis and Suspension
Fork: KYB with coatings and revalved to suit rider
Handlebars: Pro Taper SX High bend
Grips: Pro Taper
Clamps: OEM in forward / forward
Chain: DID ERT3 520
Tyres: Dunlop MX 33 with Dunlop Mousse
Seat Cover: Gripper from Top Line
Yamaha Motor Australia: https://www.yamaha-motor.com.au/
Yamaha Genuine Parts and Accessories / Yamalube: https://shop.yamaha-motor.com.au/
Ficeda Accessories: http://www.ficeda.com.au/ (Dunlop / Scott /Just 1/ DID / JT / NGK/ Unifilter)
Serco: https://www.serco.com.au/(Pro Taper handlebars and grips / Decals)