If the current fourstrokes are that good, then level the playing field and let them compete directly with 2 strokes of the same capacity. But no, they are slower, heavier, more complicated, louder, more fragile and drastically more expensive to modify and maintain. Yep the benefits are just endless…
Well, since the topic of the end of MX as we know it was brought up, lets look at that! We had the same arguments brought out when the 2-smokers took over from the old 4-strokers! Same thing was said in Baja racing when the 2-smokers took over and then again when the 4-strokers took it back?
How does all of this stuff happen time after time? Well I and probably a few of you remember when the 500cc class was the Premier Class of the World MX scene! How did we get to the 250cc smoker being the "OPEN" class and the 125cc smokers the support class? Seems that the 500cc engines from Honda, Kawasaki, Maico, Husky, Suzuki etc.. all got to be basically beyond "mere mortal" control. Yes there were always a couple of brave young fools at each track that could give them a good run but only the Pros had a chance at really getting the most out of the bikes. In fact, at many tracks, the 250cc bikes were turning lap times as fast or faster because their riders could actually hang onto them with the throttle wide open!! HA!HA!
So the ranks of the Old Open Class 500cc bikes got smaller and smaller until suddenly someone got the idea to run an overbored 250 in the Open Class. 267cc and such were running with the big bikes because they were easier to ride and more riders could get the best out of them! They even started winning on a regular basis in the Open Class against the 500s... Now the sales of the 500cc bikes dropped further and many tracks actually made the big bore 250s Illegal to ride in the Open Class "unfair advantage" it was called! Who knew. But since most tracks couldn't get a healthy start line full of 500cc bikes and the 250s were turning faster lap times and were more "affordable" than the big 500s a lot of the tracks dropped the 500cc class altogether! The AMA certainly did in the USA. World MX was a little different scene but for the USA the "Open Class 500cc bikes" were gone.
Due to the lower power rating the AMA made an allowance for the the 4-strokers to run bigger engines, actually up to 550cc in order to allow them to try to compete with the lightweight and FAST 2-smokers. Interesting concept and probably the ONLY bikes that might have been able to compete would have been those "quirky and unreliable" Husabergs which were the ony 4-strokers built to be competitive with the 250 2-smokers. Can't really consider the likes of the VOR and other "specialty" bikes and certainly couldn't consider things like the old DR Suzukis or the XR Hondas as they weren't built for MX at all.
So along comes Yamaha with their Custom Euro raced and proven YZM400F, which was probably not long a 400cc engine and certainly wasn't a production model! But they did follow up with a heavier lower powered model for sale to the public and a number of riders found that it was easier to ride to its potential than a fast running 2-smoker. Better low end power and you didn't have to keep it redlined as much around the track. Torque I believe it was called and broad powerband which the 2-smoker MX bikes had tuned away from in order to get more Peak HP from their engines. So suddenly the 4-strokers were close to being competitive, not quite there except for a few Factory bikes ridden by people like Doug Henry and a couple of well known Euro riders winning World Championships in their Open Class racing! with several years of development and Honda and Suzuki and Kawasaki seeing some market potential for sales, the field expanded and the race bikes got better. Good enough so that the fastest riders on the 450 4-strokers were making thefastesst lap timeswhen compared to the fastest riders on the 2-smokers. Development surged on the strokers and lagged on the smokers. Kind of a turn-around from the '70s when the smokers got all of the development and the 4-strokers lagged behind.
So, what killed off the smokers? Fairly easy question, Sales! Win on Sunday and sell on Monday is a nice saying but it doesn't cover everything involved, the 4-stroke engine makes more riders competitive because they are easier to ride to their potential and go fast on. "Joe Average Racer" becomes "Joe Above average Racer"! Maybe not expert or Pro Level but "better" on the track. Do they cost more to race and repair? Certainly and they also require a fair mechanic to keep them running their best. Can't put them away wet and drag them out next Sunday! Maybe some of our "mechanics“ got lazy working on simple 2-smokers and forgot or never really wanted to learn how to keep a fast running stroker running at its best! That doesn't really matter, the current 450cc 4-strokers are the fastest on the track. Maybe they should be given their own class, "Open Class“ and be allowed to run with 500cc 2-strokers? Dosn't sound like a bad idea to me. I also like the ides of running the 125cc smokers and the 250cc strokers separate! Look how many classes used to be run for a race day? Go back to 45minute motos and run outdoor natural terrain tracks! I'll go and watch!