Hirohide Tamaki - Suzuki Factory Engineer

Hirohide Tamaki - Suzuki Factory Engineer

     Hirohide Tamaki pictured on the left, designed every single works Suzuki motocross bike from 1965 to 1983.

 As with all professional racing teams, there are many people behind the scenes that make up the team. Each person has a specific and specialized job that contributes to the best organized effort possible against other teams with similar budgets and programs. All have the same goal to win. Each team is made up of hundreds of people such as engineers, draftsmen, fabricators, welders, machinists, mechanics, test riders, secretaries and even guys that just take out the trash. Most of the time these people behind the scenes go unnoticed and other than a pay check, get very little reward. When you think of Suzuki's historical racing success, Joel Robert, Roger DeCoster, Mark Barnett and Kent Howerton are just a few names that come to mind. The bikes they rode were so advanced, so light, so trick and so unobtainable to the everyone but the best riders in the world. Everyone had dreams of riding one of these hand made exotics. The other side of a snow fence was about as close as anybody other than a factory employee could get to them. How did these bikes get to be? Why do they work so good? Who designs them?  These questions were always a mystery to the motocross fan in the works bike era. Who were these people from this far away land that build these amazing bikes that had us all dreaming?

Recently we got to meet one of these people that worked behind the scenes and it wasn't the janitor. We got to meet one of the most important people on the entire works Suzuki team. The man that actually designed Joel Robert's and Roger DeCoster's world championship Suzuki's. The man is none other than Suzuki factory engineer Hirohide Tamaki. Not only did Mr. Tamaki design those bikes, he designed every single works Suzuki motocross bike other than the engine from 1964 until 1983. Absolutely incredible. Just think of any works Suzkuki from these years and it was Hirohide Tamaki who designed that bike. We asked Mr. Tamaki if he would write a short bio and a brief discription of what he did during his tenure at Suzuki. We hope he will share more with us as time goes on but for now, we are very grateful for what he has written below.

Hirohide Tamaki - Biography

I was employed by Suzuki right after my graduation at the mechanical engineering of Tokushima University in 1961 and was directly assigned to the Racing Department. Suzuki was participating GP road races at that time, so I designed some engine and frame parts for the road racers. In those days, I designed the first aluminum frame for road racers. In 1964, if I remember correctly, I was told to design a 250cc motocross machine. I took charge of the body and the engine was designed by another member. There was no real motocross machine in Japan, I only had a chance to see a Greeves 250 which some Australian rider brought to Japan for a race. We checked English magazines and got a rough idea of motocross machines. What we could collect were only dimensions and we could not figure out suspension settings and engine power band. Two Japanese riders participated some GP races with this machine, RH65, and the results were miserable. Olle Pettersson joined Suzuki in 1968 and Joel Robert and Sylvain Geboers in 1970. Olle told me that motocross frames should have some elasticity so I put rubber bushes in the swinging arm. Those rubber bushes had a problem in durability, and should be replaced with new ones from time to time.

I designed all MX GP machines from the beginning of our MX activities until Suzuki stopped all racing activities in 1983. At the beginning of the racing season in 1971 I was in Europe to see if our 500cc machine was competitive enough and to see how we could improve for the next year's machines. I stayed in Europe until the East German 500 GP held at Schwerin on June 27th. Then I started designing in early July. It was the same every year, start designing in July and build new machines at the end of November and then call riders to Japan for tests in December. I don't remember all the design details of the RH72 except I tried to make it as light as possible.

My careers after the racing department were chaotic. I was assigned to European Liaison Office in Brussels at the end of 1983 and stayed there for 5 years. After that they put me in the production side although it was out of my depth. Finally, they put me in the Legal Department to help them with technical matters on law suits. I completely retired from Suzuki in 2003. During my stay in Brussels, I was summoned by the California District Court for a law suit of some rear suspension patent. To sum up my career, I think I was very lucky to have chances to materialize my ideas although most of them were in failures.

Hirohide Tamaki - 2017

Roger DeCoster and Joel Robert with some members of the 1970 Suzuki motocross group


Joel Robert takes the checkerd flag at the 1970 250 Italian grand prix on the Hirohide Tamaki designed works Suzuki RH70. Mr. Tamaki used much of Olle Petterssons experience in designing this bike. When Joel tested the bike for the first time, his comments were "Give it to me just like this and I will win." The rest as they say, is history.

Suzuki's first experimental Full-Floater works bike (1979)

The very first ever working prototype Full-Floater Suzuki was built on a RH79 twin shock chassis. Photo by Hirohide Tamaki

Note the original rear shock mounts for a twin shock system have been cut away for this new revolutionary rear suspension system.

This early version is quite different than the version on Kent Howerton's works bike that was released mid 1980.

An experimental works Suzuki with a parallel swingarm designed to neutralize the chain tension effect on the suspension. From the Hirohide Tamaki archive.


Note the jackshaft below the swingarm pivot - two chains!