Works'91 YZ-W91 Main Shaft Replacement for YZ-631W1 by Yokomo  [YZ-631W1]

Replacement main shaft for the YZ-W91 family

The Yokomo YZ-631W1 is a direct replacement main shaft designed for use with the Works'91 TeamSpec-supported YZ-W91TS and YZ-W91 1/10 scale touring car chassis. This part is intended as an RC-scale spare for rebuilds and preventative maintenance when servicing the drive train or performing setup changes.

Fit and compatibility are limited to the Works'91 platform models listed above, so confirm your chassis code before ordering. The shaft serves a straightforward mechanical role in transmitting rotational force between gearbox components; when worn or damaged it can affect drivetrain smoothness and handling precision at high cornering loads.

Installation is typical for main-shaft swaps on this chassis family: remove the rear bulkhead and gearbox assembly, access the shaft and related bearings, and replace the shaft while keeping alignment and bearing preload consistent with the factory layout. Use basic RC workshop tools and follow standard cleanliness and lubrication practices during reassembly to avoid premature wear.

For setup and tuning, replacing the main shaft is part of routine maintenance rather than a tuning modification: it restores original drivetrain geometry and helps maintain predictable throttle response and handling balance after extended running or after impact repairs.