Words: Rob Holyoake | Lead Image: Yamaha Motor Europe
When the opportunity to test the 2021 YZ250F arose, I obviously jumped at it. The fact that the launch took place at the historic circuit of Bilstein (a regular on the ADAC MX Masters schedule and host of the 1981 Motocross of Nations, where Team USA claimed their maiden victory) was just a bonus. I was eager to get out and ride; half of the track lies in dense woodland and after crossing a road, tarmac and all, the other half sits on a grassy hillside. An idyllic setting for a motocross track.
Yamaha has given the 2021 YZ250F updates that almost mirror what they improved on the YZ450F for 2020. The chassis has had refinements to the twin-spar section at the top of the frame and the walls have been made thinner. To complement this, they have thickened the frame cradle and changed the material that the engine mounts are made out of. The top engine mounts are made of steel and the front mounts of aluminium. Additionally, the top triple clamp has been redesigned to produce a difference flex characteristic and the bar position has been moved forward. The wheel spindle has also been made thicker on the inner diameter to work in harmony with the other changes up front. I noticed these changes the most at corner entry, as the front end had a confidence-inspiring feel that let me push hard into the corners and carry momentum. Such a feeling is extremely important on the smaller bike. Overall, it gave the bike a slightly more precise feeling. It felt as if I could be very accurate with where I placed the wheels when it came to the slower, technical sections.
The 2021 YZ250F is still running the KYB SSS forks and KYB shock. From standard it is great suspension and has amazing potential to be really dialled in for any rider with a bit of tweaking. The shock and fork settings have been revised for low to mid damping. The shock felt good when riding the bike – it had a good feeling on choppy bumps at low speed. The forks felt comfortable at low speed, but I felt they were a little soft at the top of the stroke on higher speed sections of the track. This would make the forks dive a little and at speed the front felt a little unstable at times. There was a section on the track that had a hard G-out and I noticed it there specifically. Suspension is such a ball-park area, however, because of the varied size and abilities of riders. The KYB forks are the best standard forks on the market and with some basic set-up changes, they will be dialled in for you.
The bike has received some updates to improve mid to top-end performance, engine-wise, as the cam lift has been reduced by 0.3mm and valve overlap has also been reduced from 81° to 72°. The air intake has been given some much needed updates and the airbox lid has been given some extra intake vents too. To further this, they have increased the volume of the intake port to let the bike breathe. Giving the bike a more pleasant exhaust note, they have lengthened the silencer 70mm and increased the volume 340cc. I could feel how much stronger the engine was in the mid-range and top end almost immediately – it really made the bike easier to ride compared to its predecessor. Progression of the power through the range was stronger and the over-rev was improved as well. If needs be, it can be revved extremely hard. Engine braking has also been reduced, which really compliments the chassis and gives the bike more stability at corner entry.
To really bring the package together, the bike has been blessed with the same brakes as its big brother (a new front calliper, disc, and pad). The rear has a new calliper, mount and smaller 240mm disc. The front brake is very powerful but has great modulation. It had a positive connected feeling from my input on the lever to my front wheel on the track surface. The rear brake has a softer feeling and I think that helped the stability of the bike under braking massively due to it being harder to lock up.
Like the 2020 YZ450F, the new YZ250F has an on-the-fly map switch. This means that you are able to switch between two maps whilst riding with little effort. When you download the ‘Power Tuner App’ then there are three pre-made maps with the option to create your own. In my experience, the app is more of a trial-and-error process. I would pick my favourite from the pre-existing maps and then base the custom map off of that. If you are prepared to learn how to use it then you can reap the benefits of having a power characteristic that is tailored for you.
I was also able to test a fully kitted GYTR bike, as well as a YZ250F in standard trim. GYTR is Yamaha’s in-house tuning department and their main goal is to provide performance parts that are effective yet will not compromise on reliability. I could tell the difference as soon as I started the bike – the engine note was much more aggressive. The difference was impressive whilst riding too. It was graced with more power right across the range! I found that I could run a gear higher than I could on the standard bike in a few sections, simply because it had so much more grunt – more mid and top. So much so that I asked one of the mechanics after if they had changed the gearing. The answer was no! If you wanted to race a YZ250F at a national or higher level, the GYTR kit should definitely be considered as an upgrade to an already great base.
Overall, I feel the bike has benefitted from all of the small refinements that have culminated into a bigger improvement. I really liked how stable the bike felt on corner entry and I also loved having a motor that was a little stronger in the top end than the previous motor. The chassis and engine work together really well to give great feedback and feeling to the rider. The stopping power of the new brakes gives you the confidence to push the limit. It is a comfortable bike to ride for all abilities and with some basic set-up changes, to personalise the steed for you, it will be a competitive bike at a local and amateur level. If you were to race it at a higher level, the GYTR kit will give you the extra edge that you are looking for.