By now many of you awaiting the release of the all-new #YZ4SF have seen the many pre-order announcements but no official close-up shots. But as we wait for those close-up shots to become available, let us go over those teaser shots of the new diffs, height-adjustable housings and arms recently posted by project lead Shin Adachi.
During the initial stages of development, some of the key features addressed by the team were
1) an efficient driveline
2) easy access to the diffs
3) adjustable diff height.
Two key goals to achieve an efficient driveline were reduced rotational mass, and minimal center shaft angles. The new gear diffs feature a thin bevel ring gear with a center cut-out design to reduce weight, and the input gear designed for minimal mass as well. However both are made from steel so that strength and durability are not compromised. The center shaft angles throughout the driveline have also been reduced to a minimum, to eliminate as much driveline bind as possible. This helps to provide excellent power delivery, acceleration, and throttle response. Certainly a huge plus in the stock motor categories that have seen a big increase in popularity.
As you can see from the photos the diffs are enclosed in transmission housings to keep out dust and debris. The transmission housings mount into machined aluminum bulkheads, with easy removal to service the diffs.
Although adjusting diff height is a common tuning feature on today's on-road touring cars, no other shaft-driven 1/10th 4wd buggy has had this feature until now. With the increasing number of carpet and astroturf tracks worldwide, diff height adjustment will undoubtedly become an important part of dialing in your setup from low to high grip. The height adjusting cams are attached the bearing holders on the housing to allow the entire housing to be raised or lowered, effectively raising or lowering the diff as well.
New lower suspension arms were also developed, with an improved plastic formula used for both increased stiffness and durability.
This covers just a few of the great new features on the #YZ4SF, with more details to be uncovered soon!
Yokomo's New YZ-4 SF 4wd Buggy had the perfect debut just 2 weeks ago in Xiamen, China where Yokomo Factory Driver Ryan Maifield Won the 2017 IFMAR 4wd Buggy World Championship!
This is the most advanced shaft drive 4wd off-road buggy on the market.
Since the release of hi-power brushless motors, the YZ-4 SF has been carefully designed around this. With the motors anti torque and vertical motor mount layout being a key factor in not causing an imbalance in steering. Now this shaft drive car can perform more aggressively while staying stable even through difficult jump and cornering sections.
Of course, excellent throttle response is delivered by this unique shaft drive system while also remaining dirt/dust proof. The YZ-4 SF has been designed so that regular drive train maintenance is very easy.
The front and rear aluminum gear box's are sealed very well and the height of the bulkhead can be easily adjusted by exchanging the eccentric cam on both sides. Fine-tuning the differential position (the angle of the dog bone) against the height and suspension geometry is an important setting option which has a significant impact on the overall raction and cornering of the car. It's possible to match the various track conditions and driving styles to provide the perfect balance from the front to the rear of the car. This will prove to be a big advantage in fine tuning each set-up.
Also, the YZ-4 SF kit includes two types of front and rear shock springs. Both for low-grip surfaces such as dirt, along with high-grip surfaces such as carpet and astro. Front and rear stabilizer bars, along with gear differential oils are all included so each customer can select the ideal set-up for their specific surface.
World Championship proven performance with the freedom to make multiple set-up changes allows you to drive the best in any off-road situation.
Features of YZ-4 SF
Shaft Drive 4wd System
Aluminum Hard Anodized Main Chassis
Multiple Springs for Dirt, Carpet, & Astro
Stabilizer Bars & Differential Oils Included in Kits
Big Bore X33 Super Low Friction Shock Absorbers
Aluminum Front/Rear Bulkhead and Caps
Graphite Carbon Front/Rear Shock Towers
Front/Rear Gear Differential Box's with Adjustable Height Options
Aluminum Suspension Mounts (Ability to Easily Change Geometry)
New Front/Rear Suspension Arms and Steering Hub Carriers
Lubricated Front/Rear Gear Differentials
New Light Weight Designed Slipper Assembly (3 pad system)
Aluminum/Carbon Graphite Floating Servo Mount
New JConcepts YZ-4 FS Clear Body & Wing