Casting one’s eyes upon championship-winning motocross bikes—the actual bikes that crossed finish lines to win number-one plates—can be, if one is open to it, a mesmerizing crash course in moto history. Nowhere is this dynamic more evident than in the lobby of the big white building visible from the 91 freeway in Corona, California. Motocross Action swung by Pro Circuit to catch up with Pro Circuit overlord and mastermind Mitch Payton. We let Mitch hand picked six of the bikes in his museum. Here is bike number five.

By Eric Johnson/Photos: Ryne Swanberg


ON THE TRANSITION TO FOUR-STROKES: “From 1980 through 2003, I spent all my time and effort trying to be the very best two-stroke guy that I could be. The true black art of everything on the two-stroke was the pipe, and there weren’t that many really super-smart guys who had a real grasp on pipe design. The guy who helped me the most was Paul Turner. He understood the cylinder and the head, but most of all he understood how a pipe worked. Two-stroke engine tuning was my whole life, and then all of a sudden the four-stroke thing shows up. I thought four-strokes were dumb. But it became obvious that if we didn’t embrace four-strokes, we were going to get run over.”

FINDING A MENTOR: “I knew I was going to have to learn how to build fast four-strokes. I was fortunate enough to know a guy named Drino Miller. Drino had worked for Andial Porsche and ran TRD [Toyota Racing Development]. He had this wide, vast experience of race-engine stuff. So, we had Drino come to the shop and he asked me what my goal was. I said that I wanted to make the best pistons, cams, valve springs and do everything to make a four-stroke fast. Everybody else was buying existing parts from vendors and putting them together. I didn’t want to do that. I wanted the best piston, cam, rod and valve companies to build parts for us exclusively. Del West built our valves for us because I thought they were the best valve company in the industry. They had done F1, and they understood what they were doing. Del West still builds our valves, keepers and retainers.”

THE 2004 KX250F: “When we got the KX250F it wasn’t very fast. At that point, I knew how much power we could get out of a Yamaha, and we weren’t even close with the Kawasaki. I knew we had a lot of work to do.”

IVAN MADE THE SWITCH: “When we signed Ivan Tedesco for 2004, he wanted to race a two-stroke. After the AMA passed the unleaded fuel rule, we had to lower the compression and change the jetting. The two-stroke lost the pizzazz it had the year before. I told Ivan, ‘You should rethink riding the four-stroke, because that thing is going to do nothing but get faster, and the 125 two-stroke is maxed out.’ Ivan rode both bikes and his starts were better on the KX250F four-stroke and he was faster in the whoops on the four-stroke. Ivan said, ‘Okay, I’m going to race the four-stroke.’ From then on he was awesome and just started winning right away. It was a lot of work to get through 2004, but very rewarding.”


To read Part One on Jeremy McGrath’s 1992 Team Peak Honda, click here.

To read Part Two on Mickael Pichon’s 1995 SplitFire KX125, click here.

To read Part Three on Ricky Carmichael’s 1997 SplitFire KX125, click here.

To read Part Four on Mike Brown’s 2001 MXDN KX125, click here.

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