As motorcycle engine technology transitioned from the 60 horsepower four-stroke motorcycles of the 1960s, to the 100 horsepower two-stroke motorcycles of the 1970s, it became apparent that motorcycle tire technology was lagging behind engine performance on the track's banking. In an effort to slow the fastest bikes down and save on tire wear, a chicane was added in 1973 at the end of the Daytona back straight. The dangers that motorcycle racers were exposed to was highlighted in 1975 when a documentary crew were filming as Barry Sheene crashed on the banked track at over 170 mph when his rear tire failed. As speeds continued to increase, organizers eventually moved away from high powered Grand Prix-style motorcycles to highly modified production motorcycles known as Superbikes in 1985, which led to a global trend of Superbike racing that by 1988 would lead to the development of an FIM-sanctioned Superbike World Championship in 1988. The loss of Grand Prix machinery meant that fewer international competitors were interested in entering the race and, began a slow decline in the event's prestige.
