Yokomo have introduced new option parts for the YD-2 EXII in the form of a set of rear suspension parts and an aluminium rear shock tower. First up is a shorter rear suspension set, includes rear suspension arms, aluminium rear suspension arm mount “D”（57.2～60.4mm) and aluminium rear suspension arm mount ”E” (60.8～64.0mm). After various combinations in tests, it has been shown that the use of too long arms provides instability of the braking at the rear and that affects the vertical traction. Yokomo chose a standard combination (RF 59.6ｍｍ/RR 61.2mm) and adapted it to different surfaces like asphalt or carpet to get the right configuration:
- Asphalt (RF 59.6mm/RR 62.0mm): 1.6 degree
- Tile (RF 59.6mm/RR 61.2mm): 1.1degree
- Carpet (RF 58.8mm/RR 62.4mm): 2.4degree
Notice that toe angle and suspension mount combinations are different following the track surface type.
Next up is the aluminum rear shock tower. Made from high-quality aluminium, it comes grey anodised. The rear shock tower offers a length of the lower and upper suspension arms more equal. This allows a better vertical and horizontal balances, and provides more traction with short suspension arms.