2004-2009 Honda TRX450R/TRX450ER Service Manual, Page 93Get this manual
MAINTENANCE BRAKE PEDAL HEIGHT ADJUSTMENT Remove the right mud guard (page 3-3)Loosen the lock nut and turn the rear master cylinder push rod to obtain the desired pedal heightTighten the lock nut after adjustmentTORQUE: 18 N-m (1.8 kgf-m, 13 Ibfft)
If the brake pedal is adjusted to the lower position, make sure that the clearance between the lower end of the push rod and the brake pedal does not fall below mm (0.04 in)If the brake pedal is adjusted to the higher position, make sure that the lower end of the push rod thread is visible inside the joint