The 2017 and 2016 YZF450 are similar bikes. We prefer the handling / steering of the latest model over the previous 2014-15 models. The 2016 pushed the fork forward making the bike more stable and turn slower. They did reduce the compression valving on the 2016 forks creating a bottoming issue and vague feeling for some riders. With the proper front set up, this is a well balanced bike that offers tried and true suspension components.
The 2014 - 15 models steered a bit like the CRF's. Probably too much weight on the front end made the bike a fast turning maching that worked great on a tight MX track, but lacked some stability at higher speeds. We have had great success with all of our late model YZ's because of a solid frame and good components.
THE NEW 2010 CHASSIS:
The new 2010 & 2011 YZF450 frame geometry orients the bike more towards moto cross than 09 and earlier models. When we did our Too Tech modified bike shoot out between a 2010 YZ, a 2008 CR450R, and a 2008 YZF450, we found the 10 YZ and the 08 CR to have extremely similar traits on a tight MX track. I personally gave the nod to the 10 YZ in the ruts because it was easier to follow radius changes, probably because of the centralized weight distribution of the YZ. The 08 YZ (similar to 09) felt comparatively slow and required more deliberate input for turning on the tight track. Conversely the 08 YZ stability shines in more open terrain MX and the off road environment.
The only disadvantage noted for the new 2010/11 YZF450 is that the quicker steering requires very fine tuned suspension. Many suspension companies will find their style of re-valving inadequate to calm the high speed handling traits of this new chassis. Too Tech's extensive experience with Honda chassis layout and quick steering geometry provides the background to deal with the new YZ. Give us the chance to transform your new YZ.
The 2008 & 2009 YZF450 frame geometry is a great compromise between tight turns and stability. It works great for outdoor MX and off road. However, they are valved even stiffer than the 2007. This will make the harshness worse and the bike will be more likely to deflect and get knocked off course going into turns. We are using settings we perfected since the new 2006 frame and forks were released in 2006 with great results.
Cartridge type Fork (2005 and up) YZF OBSERVATIONS
YZ suspension performance has improved dramatically since they changed to the Internal Chamber KYB fork design. Yamaha likes to call this fork 48mm fork design a speed sensitive damping (even though all hydraulic shock absorbers vary damping as a function of speed). The KYB YZ fork is a carbon copy of the Showa CR fork except that the air volume above the Internal Pressure Spring is kept separate from the fork slider air volume making the KYB a 3 chamber design. In the '2 chamber' Showa design, fork slider air pressure is applied on top of the Internal Spring. Thus as the Showa fork moves through it's stroke, the fork slider air compresses and applies pressure on top of the Internal Spring which aids spring pressure and causing the damping to become firmer. Because the YZ 3 chamber design prevents the fork slider air pressure from aiding the Internal Spring, Internal Spring forces remain constant throughout fork travel. Because of the 3 chamber design, the KYB damping is less affected by fork displacement than the Showa.
Ideal rider weight for the 450F is 170 to 190 pounds while ideal weight for the 250F is 140 to 160 pounds. Heavier riders will usually feel their bikes are too soft! This is because the front & rear springs do not adequately support their body weight. The bike will dive too low in the front under braking and squat to low in the rear under acceleration. When the suspension compresses too far under braking and acceleration, there is not enough travel left to absorb the next bump. So even though the bike feels soft in most situations, it will become very stiff when it runs out of travel in rough terrain.
The first step to proper bike set up is to install the correct springs. Please visit my
"Rear Spring Static Sag" page to check your rear spring rate or give me a call to discuss the optimum front and rear springs for your weight, riding terrain, and rider preferences.
Once the proper springs are installed into your bike, it will then fit the 'ideal rider weight' evaluations discussed below.
YZF 250 Riding impressions for the ideal rider weight of 140 to 160 pounds.
- Front end rides high in the stroke, won’t dive into a corner, and feels harsh in square edges. Symptoms include jolts to your hands, arms, and shoulders along with difficulty initiating tight turns.
- Rear end deflects when accelerating hard through acceleration bumps. Tends to get knocked off course at high speeds or when slowing in braking bumps. Symptoms include being deflected off course when aiming for a rut or accelerating for a double jump. Trail riders will notice harshness and deflection when hitting rocks or tree roots.
- In the rolling bumps, big jumps, and well groomed tracks the bike should feel OK. Problems are accentuated by rough terrain.
Situation & Solution
The front fork valving is almost identical to the YZF450. The excess fork valving causes the front end to resist quick transitions, resist diving into turns, and provides too much feedback from the terrain - feels harsh. Revalving the forks for more compliant action and reducing the pressure spring rate restores the plushness and promotes front-end turning and more dive. For less aggressive riders and trail riders, we utilize multiple stages of compression valving to further increase plushness.
The rear shock valving has remained similar year to last year. The stiff high-speed compression damping causes the rear to deflect of sharp bumps. This is most noticeable when accelerating hard through the chop. Too Tech internal revalving includes a new rebound tuning strategy along with extensive adjuster modifications that relieve the high-speed compression kick.
For lighter riders, we recommend a 4.8 rear and .43 front springs. Lighter springs allow lighter riders to compress the front end into turns allowing tighter turn and good weight transfer to the rear under acceleration..
For aggressive riders in the ideal weight group, or riders over 170 pounds, consider 5.2 rear springs and .45 springs in the front to control front end and rear squat.
YZF450 Riding Impressions for riders weighing between 170 to 190 pounds
Very similar to the 250F except that the problems are amplified due to the increased weight and power. On smooth well groomed tracks the bike is a pleasure, but as the track roughens during the day the bike becomes harder to stay on line and the harshness tires out the rider
- Front end rides high in the stroke and feels harsh in square edges. Tends to get knocked off course when trying to hit a precise line. Rider will tire out quickly. Symptoms include jolts to your hands, arms, and shoulders along with difficulty initiating tight turns and staying in ruts.
- Rear end deflects when accelerating hard through acceleration bumps. (This becomes more noticeable after fixing the front end) Symptoms include being deflected off course when aiming for a rut or accelerating for a double jump. Trail riders will notice harshness and deflection when hitting rocks or tree roots. Many riders think their shock is good, but they do not realize how much the rear is affecting the performance of the bikes front ends.
- In the rolling bumps, big jumps, and well groomed tracks the bike should feel OK. Problems are accentuated by rough terrain.
Situation & Solution
The front fork valving has excess low speed damping for all but the best of the best or heavy riders. This excess valving causes the front end to resist quick transitions and resist diving. Revalving the forks for more compliant action and reducing the pressure spring rate restores the plushness and promotes front-end turning and better dive.
The rear shock valving remains similar year to year although the shaft size was increased for 2006. The stiff high-speed compression damping causes the rear to deflect off sharp acceleration or high-speed bumps. The increased shock shaft diameter adds to the stiff feel for technical reasons inside the adjuster. Too Tech revalving includes a new rebound valving along with extensive adjuster modifications and valve stack changes to produce a more linear compression valving rate.
The forks have .47 kg/mm springs and the shock has a 5.4. Slower less aggressive riders will benefit from softer springs. Many lighter riders get static sag numbers over 1 ½” which indicates they should move down to a 5.2 rear and .46 front springs..
Overall, the single most important change I make to the YZF suspension is to reduce the energy required to ride the bike. For a trail rider it means he is less exhausted at the end of the day. To a racer it means he can be as strong the last five minutes of the race as he was the first five minutes.
Please call me to discuss your specific complaints and needs to satisfy your expectations!
