It seems that Honda forks and twin leading shoe brakes are the bulk of the problem, the brakes in my mind are a safety thing and should be allowed, and most could afford to do it, IF THEY WANTED TO. Honda RC bikes have had different variants of 43mm Showa forks from as far back as 1977 and I guess if I had the cash and made enough effort back then to get a set I probably could have. Honda didn't bring them to a production bike until 1983 even though they had been around a long time beforehand. Still If I fit a set I'll be "cheating" and if I go one step further and fit a 480 engine so I can have a big bore Honda EVO bike, I once again will be "cheating". If however I stick with the rules to the letter, and fit a set of Husky 40mm forks, twin shoe brake and a CR/WR 500 air cooled engine from 1984 to my Honda, even though it will no longer be a Honda persay, I will be fine and allowed to race. I have now destroyed my Honda and have the Hybrid bike that everyone fears, but am legal to race. Go figure. For probably 90% of us, it doesn't matter what we ride, the top 10% will still be able to beat us on an XR75. Twin shock, no linkage, air cooled = EVO. A '79 CR with a 480 motor aint going to be any different than a '79 RM400 with an 84mm piston (460cc or thereabouts, which is easily done). In my mind no one is cheating, they just have different tastes. It's more about whatever floats your boat than cheating.