Works'91 TeamSpec YZ-W91 Main Shaft Upgrade for YZ-631W1 Yokomo  [YZ-631W1]

Main shaft details for YZ-W91 platforms

The Yokomo YZ-631W1 is produced as a direct replacement main shaft intended for the Works'91 TeamSpec YZ-W91TS and YZ-W91 1/10 touring car chassis. It functions as a serviceable spare for rebuilds and preventative maintenance during drivetrain servicing or setup revisions.

Ensure your vehicle matches the Works'91 models named here before ordering because fitment is limited to those chassis codes. The shaft is a key drivetrain component transmitting rotational load; when degraded it can introduce vibration and inconsistent handling at high cornering forces.

Installation follows the typical sequence for this family: strip the rear bulkhead and gearbox, exchange the shaft and bearings, and reassemble while preserving alignment and bearing preload consistent with factory tolerances. Work cleanly and use standard RC tools and greases to prevent premature wear.

Replacing the main shaft is generally regarded as maintenance rather than a performance tweak. A fresh shaft returns the drivetrain to its intended geometry and helps keep throttle response and balance consistent after long service life or crash repairs.