Mugen MRX-5 1st Gear 17T Hard-Coated Pinion - MUGEN AM-MRX5-H0758 Arrowmax  [AM-MRX5-H0758]

First-stage pinion summary

Arrowmax supplies the AM-MRX5-H0758 1st gear as an aftermarket pinion for the Mugen MRX-5 clutch/pinion system. Manufactured from 7075-T6 aluminium with a hard coat, the part is designed to cut rotating weight while improving resistance to wear, without modifying the factory clutch interface. Tooth choices from 16T to 21T give a range for tuning launch and low-speed drive characteristics.

Fitment follows the usual MRX-5 procedure: take the stock first gear off the clutch bell, slide the Arrowmax pinion onto the clutch/pinion hub, then set and check mesh with the spur. Carry out a short break-in run and check gear temperature and noise before extended running.

Adjusting the 1st gear tooth count changes the effective final drive during initial engagement; fewer teeth favour faster spool-up while more teeth raise first-stage gearing a touch. Use the supplied tooth range to fine-tune launch behaviour and throttle response to match track conditions.

Compatible chassis

• Mugen MRX-5