BD9 Centre Bulk Belt Tensioner Kit - Yokomo B9-RBTSA  [B9-RBTSA]

Stabilising the BD9 rear belt run

The Yokomo B9-RBTSA rear belt tensioner is an aftermarket accessory designed to fit at the centre bulk of BD9-format touring cars to manage the rear belt route. It suppresses belt flapping that can trigger tooth skip, helping to keep consistent belt engagement during dynamic driving.

The unit is only compatible with the chassis listed below; it mounts on the centre bulk and functions by preserving an optimal belt angle and controlled tension at the contact point rather than modifying belt length or drivetrain layout. Acting directly on the belt run, the tensioner helps lessen intermittent drivetrain backlash that can present as skipped teeth when the system is under load.

Installation and adjustment are user-friendly: fasten the tensioner so the roller or contact area lines up with the belt, check for clearance from adjacent parts, then validate belt tracking under static checks and slow-speed runs. Small positional tweaks help dial out slack or prevent excessive tension—inspect belt wear and drivetrain feel after initial sessions and re-check alignment as part of routine maintenance.

This component is intended for maintenance and tuning of BD9 touring car drivetrains.

Compatible Models

• MRTC-BD919
• MRTC-BD919S