mooch ,
I read your thread on the vintage site . Interesting . To me , the whole vintage dealio is about riding cool old bikes , not necessarily the BEST of the lot , but bikes you always admired , wanted , and maybe couldn't afford way back when . Super Hunky , Rick Sieman , wrote a list of what he considers the 10 worst MX bikes ever created . I have ridden many of those and actually owned two of them , a 1973 Yamaha SC500 and a 1981 Honda CR450R . I loved both those bikes , spent a lot of time and $ modding them to my liking , and was as competitive on them as I probably would have been on anything else . Wish I had them both back . My current favorite is my 84 Husky CR500 which has dual rear shocks , front and rear drum brakes , and no water cooling : talk about being obsolete the day it rolled off the production line ! I LOVE this bike ( even though the SOB is almost impossible to start ) and prefer it over the other big bores of the day . I don't know about the AMA class structure but in AHRMA , these bikes like my 500 and the 490 Maico run in the Gran Prix class against like machines . The " modern " single shock , water pumpers run in Ultima . To me that makes the guy's " obsolete " opinion a non-issue . The big equalizer has always been rider talent . Plenty of races have been won on " inferior " equipment and I know guys who could probably best me and my 500 even if they were on a clapped out Hodaka with blown shocks .
On another note , the big bore bikes ( and even the 250s ) of that era are TALL . I can barely touch toes to ground on the Husky and usually stand on a block of some kind when I feel frisky enough to try and kick start it , instead of doing the " walk of shame " to push it to the bump start hill . If I remember correctly you are my height or a bit less . Scott is probably 3 inches taller than me and has trouble kicking those 81 maicos ( 81 is the year not the # he owns but he may be getting close ) without standing on something . A lot of the old big bores had starting and kicker shaft issues due to the force needed to get those big pistons and long rods through their stroke . Just a couple points you might want to consider .