1968

In 1968, Yamaha won all 10 races of the season to reclaim the manufacturer's title as well as the rider's title, won by Phil Read, which became his third championship title in the 250cc class. Read also took the 125cc class title for double championship on the season.

With an increasing number of cylinders and high power output of the engines by manufacturers, FIM introduced a new regulation set to come into effect from 1970 that would limit the 125cc class to a single-cylinder engines and the 250cc class to twin cylinders, as well as restricting the transmissions to 6-speeds. After this announcement, Honda and Suzuki made their decision to leave the sport. However, Yamaha continued to take part in 1968. Yamaha brought in the liquid-cooled V4 machine RD05A, which had narrowly missed the title in the previous season. This machine was ridden by Yamaha's top British riders Read and Ivy.

The opening round was held on the 20th of April at Nurburgring in West Germany. Read and Ivy were onto a good pace from the first race and won, while also recording the fastest lap time. They never allowed their rivals to take the lead once throughout the race. In Spain and the Isle of Man, Read and Ivy took a win each. Yamaha went on to claim a streak of wins ? Ivy and Read took a one-two finish with only a tenth of a second gap in the Netherlands. In the Belgian GP, Read showed a superb comeback from the back of the pack to overtake the leading MZ riders after pitting for a spark plug change. There was another tenth of a second gap finish for Ivy and Read in East Germany. Ivy's win in East Germany clinched the manufacturer's title for once more for Yamaha

The championship battle between the Yamaha riders did not end after the 9th round in Finland, and it all came down to the last race. The final race of the season was held on the 15th of September in Monza, Italy. Out of the nine races up to this point, Ivy had taken five wins while Read took four. The race was held despite the rain on the previous evening. Read, who was not on his best form in qualifying, brought himself back into contention to lead the race and win with a 1'50 gap over Ivy. The points between the two riders (effective points from six races) were tied after this result. The FIM regulation stated that the race times of both riders must be compared in this circumstance. The data showed that Read had a much better total race time, and so he was crowned the champion. This year riders Rodney Gould, Kent Andersson, Barry Smith and Jack Findlay also won series points riding Yamaha machines.

Yamaha riders for the 9-race season of the 125cc class in 1968 were last year's champions Ivy and Read. This time, Read took the rider's title for both 125cc and 250cc classes. The manufacturer's title was also in the hands of Yamaha, which lead to a consecutive rider and manufacturer's title. This season's RA31A was an updated version of the liquid-cooled, 2-stroke, V4 powered machine RA31, which was ridden by Ivy in the previous year.

The opening race was held on the 21st of April in Nurburgring, West Germany. Other manufacturers competing that season were Suzuki, MZ and Bultaco. Ivy, who started in pole, and subsequently retired from the race. Read on the other hand placed a gap of over 10 seconds against the rest of the pack to run well in front of the others for most of the 13-lap race. Apart from the second round where Bultaco made a one-two finish, Yamaha dominated the championship race. Read won the third round at the Isle of Man, and in the Netherlands, Read overtook the Kawasaki with its 2-cylinder engine which was leading in the early stages of the race and finished the race two minutes ahead of the second-place rider. Read continued on to win in East Germany and Czechoslovakia, and his win in Czechoslovakia gave him the rider's title for the season. His race pace was staggering there as well and he finished two minutes ahead of the second placed MZ rider. Read continued his winning streak in Finland. Ivy went on to take the final races at the Irish and Italian GPs and make it a season dominated by the strong performances of the two Yamaha riders.