This is taken at one of my very first "pro" races, somewhere in Idaho. I was riding my 1977 RM125 and sporting Lancer leathers and a Jofa mouthguard (open-face helmets were the norm) that I trimmed for some reason, and had a Champion sticker on my visor and gas tank. I probably never used a Champion spark plug, at least that I noticed, of for that matter any of the products that were advertised all over my bike, helmet or van. Most of the stickers we chosen for looks or for their reference to something cool or pro.
Those RM125s from the late 1970s were really good bikes, having been developed by the actual professional racers and brought to market on a very short development cycle. The 1977 RMs were wel-balanced with some very good forks and remote-reservoir shocks that kept the ride smooth and controlled. The handling was very predictable, and the great thing about 125s was, you knew exactly how fast to go: wide open all the time.