At the end of the last 20th century and for nearly a decade, the well-known SoS and Formula Supermono championships in which their grills were made up of racing motorcycles like this one 1988 Honda TH1R Ikuzawa-Harris. The idea was clear as to what was sought: a light, agile and effective mount. Assembled on a medium-displacement single-cylinder platform, generally borrowed from a trail bike, they became a fearsome knife on a mousetrap.
In an article published by Cycle World in 1986, Koichi Hirose commented in this regard: “On a short circuit in Japan, where a 500cc GP bike had set a lap record of 58 seconds, and where the 250cc record was exactly one minute, the TH IR unofficially completed a lap in one minute and four seconds, impressive for a single-cylinder four-stroke bike.”…Are we getting an idea?
Tetsu Ikuzawa: the genius behind the machine
After a project like the Honda TH1R Ikuzawa-Harris protagonist of these lines, there must undoubtedly be someone passionate about the world of two wheels. In the case of Tetsu Ikuzawa We are talking about a living myth of the motor world inside and outside the Japanese borders. He is one of Japan’s most successful motorsport drivers, having won the national Grand Prix twice, as well as the Fuji Grand Champion Series.
In addition, he was the first Japanese driver to compete in championships such as British Formula 3, European Formula 2 and the 24 Hours of Le Mans. He also served as a team manager and Japanese businessman, opening his first motorcycle store in 1984: “Just like someone who collects antiques might open an antique store, my passion for motorcycles grew and I opened a store!”he comments.
“When the editor-in-chief of the American motorcycle magazine «CYCLE WORLD» (Alan Cathcart) visited Japan, stopped by my workshop and exclaimed: “This is the most beautiful motorcycle workshop in the world!” It is a workshop with a unique style. Even other dealers in the Kansai region rented a bus to come see it,” concludes.
Competitive perfection made a motorcycle
Just two years later he had given shape, in collaboration with the British chassis specialist Harris, to this competition gem. The recently defunct American newspaper was one of the first to report on the launch of the Honda TH1R Ikuzawa-Harris. Equipped with an RS600D engine derived from the XR600R and tuned for the occasion by HRC for Dirt Track racing. managed to deliver a declared power of 61 HP at 7,000 rpm.
Although the mechanics did not stand out for their excellent figures, the secret of the Honda TH1R Ikuzawa-Harris was based (as in the rest of motorcycles of this type), on a cycle part perfected to the extreme: “Perhaps the most interesting thing is the TH 1 R chassis, manufactured by the Harris company in England”explained the Cycle World editor at the time.
He concluded in his scoop article on the launch of this Ikuzawa-Harris TH1R: “This is the same chassis design that Harris uses to build multi-cylinder Japanese Café Racers. It is made with Reynolds 531 steel tubing, Marzocchi fork, White Power rear shock from Holland, Lockheed front brake caliper and Brembo rear brake. Both the front and rear wheels are Dymag.”
The copy for sale in detail
This TH1R Ikuzawa-Harris offered by the friends of Iconic Motorbikes is, according to registration documents, the third manufactured of 20 examples in total and the first to arrive in the United States. It is associated with VIN: TH1R003 and engine number: RS600DE0006157although the sales advertisement specifies that “we couldn’t see the VIN stamped on the chassis.”
An important fact is the fact that the seller of this copy is the original owner. He purchased this unit directly from Ikuzawa and comments on it: “This bike was ordered from Ikuzawa in 1987/88 and was Ikuzawa’s first bike in the United States. I used it in private races and it has remained in my collection ever since”. He concludes by stating: “I have all correspondence with Ikuzawa during the construction and delivery stages.”
As for the aforementioned engine, in this case a closed transmission ratio was used (not specifications for flat trackers), which was also the last time this mechanism was equipped on a racing motorcycle. Furthermore, a year after its acquisition, in 1989, “The seller commissioned Muzzy R&D to rebuild and upgrade the engine with titanium valve springs and a Muzzy camshaft,” they explain from Iconic.
Other custom modifications that this Ikuzawa-Harris TH1R came with from the facilities where it was assembled include, for example, a high-performance Ceriani front fork. It also includes a swingarm to the latest specification that was fitted in this short and limited special series. It also mounts a CNC Yoke seatpost in which even the adjustment controls of the suspension system itself are also made of aluminum.
There is no doubt that we are facing a true piece of racing history that marked a golden era in the world of competition. You can consult the rest of the details (including imperfections or things to check) in the sales announcement itself. But be careful, if you are interested in getting this gem, be quick because in just a few hours the bidding will have concluded… Good luck!
