Hi,
I am building a 1975 Penton 250 to race Sportsman 250 AHRMA motocross with and am trying to determine the stock shock length for this bike and the correct upper and lower mount positions to keep it legal regarding the 4" travel rule. Thanks for all input.
Dave
I run 13.5" Konis on my 75' 250, with 1" longer top shock eyes to steepen front fork angle. I run them in the rear-most mounting position and I have a 1/4" shock shaft spacer for exactly 4" travel. I'm 6' tall and like the taller seat height and the quicker handling. I also had to install longer top-out springs in the forks for 7" fork travel. AHRMA tech WILL check travel, Make sure it's not over! I would like to move up to Works Performance shocks if I could afford them. Hope this helps, Wildman
1975 250 Cross Country, 1974 175 Jackpiner, 1975 125