If you're performing a quick tune-up and don't want to dig through a 100-page PDF, here are the critical specs for the GS150R:

25 psi (front) and 28-33 psi (rear, depending on pillion load). 12V, 5Ah Maintenance Free. Maintenance & Service Guide

A service manual is a detailed guide that provides instructions and specifications for maintaining, repairing, and troubleshooting your motorcycle. It's an essential tool for: