What oil to put in a trx 450r transmission?

For a Honda TRX 450R transmission, it is recommended to use a high-quality gear oil, typically a 10W-40 or 20W-50 motor oil that meets JASO MA specifications. Options like Honda's own GN4 or other reputable brands designed for wet clutches are ideal. Always check the owner's manual for specific recommendations to ensure optimal performance and protection.