There are not many forty three year old one owner race bikes around; but this is the story of one such bike and owner.
Keeping any motorcycle for more than forty years is rare; keeping a racing motorcycle for that long is even rarer. But one Australian owner rider, Davey Keenan, has done just that.
Back in 1970 Davey was racing a modified street Suzuki T20 when he decided he had to have a proper racer. The Yamaha factory had started to offer race kits for their very successful YDS street bikes (YDS-R) back in the early sixties. Based on the success of these early racers, Yamaha produced the TD-1 pure race bikes. The TD-1's proved that the company's previous successes in races at home and abroad was no fluke; when the TD-2 came along, the world of international motorcycle racing changed forever.
For many years, the world of international motorcycle racing in general, and Grand Prix racing in particular, had been dominated by various Italian machines, and the venerable British singles from Norton (Manx) and AJS (7R) in the bigger classes (350-cc and 500-cc). But when Yamaha owners started to bore their TR350s to 351-cc and dominate the 500-cc class (having already began to dominate the 350-cc class), the British and Italian manufacturers could not compete with the powerful, light weight, Japanese machines.
When British rider Rodney Gould from the UK won the 250-cc world championship on a private TD-2, and Australian Kel Carruthers finished 2nd on another, (note: Yamaha did not enter a factory team that year), riders from all over the world wanted one. And so Davey purchased his TD-2 from Taylor Cycles, in Hunter Street, Newcastle, Australia. The total price was $1800 (Australian dollars) which he paid half of in cash and the other half on hire purchase.
Going from a modified street bike in the Suzuki T20 to a proper race bike would have been a big jump in those days, and so it was for Davey. "To be honest, I was a little frightened of it at first. I didn't want to hurt it!" said Davey in a recent interview. All that changed when he had the inevitable first fall.
As he became more used to the capabilities of the Yamaha, his results began to improve. One notable finish was a second place in the 'B' final on the famous Bathhurst track at Mount Panorama Circuit in Bathurst, New South Wales, Australia. He was particularly proud of this result as he started 2nd to last before passing many riders on his way to second.
Owning a race bike for this length of time has given Davey an unparalleled knowledge of the weak points of the Yamaha and also what works to improve their performance.
One of the earliest modifications to the Yamaha was to replace the standard magneto/points ignition assembly with a Krober CDI unit. The change of ignition made a big improvement to starting the Yamaha, "It only took two steps to start it, so I thought something was wrong" said Davey.
Another big improvement was changing the fuel from pre-mix and gasoline to pre-mix with methanol. Davey claims this change gave an extra eight hp and helped to keep the temperature down (something the early 2-stroke air-cooled racers had a particular problem with). However, to stop the inside of the engine from rusting after using methanol, Davey ran the engine for a short time on regular gas at the end of each meeting.
Most of the 2-stroke racers have a considerable appetite for pistons and rings, and the TD-2 was no exception. The original engine used chromed bores with cast iron rings, but the harsh conditions inside a 2-stroke are not ideal for chromium plating, which tends to peel near the exhaust ports and can cause seizures--especially if the rider is running a lean mixture (see note below).
Note: The term lean, when referring to a 2-stroke, applies to the amount of fuel (gasoline typically) passing through the main jet. A lean mixture implies a reduced amount of fuel which will generally cause overheating (the gasoline also cools the piston, bore and head). A lean mixture in the US is often applied, incorrectly, to a lean amount of oil in the mixture. This would, in fact, richen the overall mixture.
To improve the cylinder reliability, Davey uses modern street bike pistons from a Honda MTX 125 combined with a change to Nikasil coating of the cylinders. Most of his other bike-specific parts come from Meadspeed in the UK.
The stock carbs have been bored out to 34-mm (from the stock 30-mm) and some 30-mm has been cut from the stock expansion chambers to improve the top-end performance.
The stock brakes have been retained as these have proven to have exceptional stopping power and even compare well with another, much later, TZ250 he has.
Davey speaks highly of the Japanese Dunlop tires he has used for a number of years, the TT900s. These tires cost around $130 (AD) for the rear and $120 (AD) for the front and typically last for a season’s racing.
1. Yamaha TD2, One Owner from New
Keeping any motorcycle for more than forty years is rare; keeping a racing motorcycle for that long is even rarer. But one Australian owner rider, Davey Keenan, has done just that.
Back in 1970 Davey was racing a modified street Suzuki T20 when he decided he had to have a proper racer. The Yamaha factory had started to offer race kits for their very successful YDS street bikes (YDS-R) back in the early sixties. Based on the success of these early racers, Yamaha produced the TD-1 pure race bikes. The TD-1's proved that the company's previous successes in races at home and abroad was no fluke; when the TD-2 came along, the world of international motorcycle racing changed forever.
For many years, the world of international motorcycle racing in general, and Grand Prix racing in particular, had been dominated by various Italian machines, and the venerable British singles from Norton (Manx) and AJS (7R) in the bigger classes (350-cc and 500-cc). But when Yamaha owners started to bore their TR350s to 351-cc and dominate the 500-cc class (having already began to dominate the 350-cc class), the British and Italian manufacturers could not compete with the powerful, light weight, Japanese machines.
When British rider Rodney Gould from the UK won the 250-cc world championship on a private TD-2, and Australian Kel Carruthers finished 2nd on another, (note: Yamaha did not enter a factory team that year), riders from all over the world wanted one. And so Davey purchased his TD-2 from Taylor Cycles, in Hunter Street, Newcastle, Australia. The total price was $1800 (Australian dollars) which he paid half of in cash and the other half on hire purchase.
2. First Impressions
Going from a modified street bike in the Suzuki T20 to a proper race bike would have been a big jump in those days, and so it was for Davey. "To be honest, I was a little frightened of it at first. I didn't want to hurt it!" said Davey in a recent interview. All that changed when he had the inevitable first fall.
As he became more used to the capabilities of the Yamaha, his results began to improve. One notable finish was a second place in the 'B' final on the famous Bathhurst track at Mount Panorama Circuit in Bathurst, New South Wales, Australia. He was particularly proud of this result as he started 2nd to last before passing many riders on his way to second.
3. Improvements to the Stock Bike
Owning a race bike for this length of time has given Davey an unparalleled knowledge of the weak points of the Yamaha and also what works to improve their performance.
One of the earliest modifications to the Yamaha was to replace the standard magneto/points ignition assembly with a Krober CDI unit. The change of ignition made a big improvement to starting the Yamaha, "It only took two steps to start it, so I thought something was wrong" said Davey.
Another big improvement was changing the fuel from pre-mix and gasoline to pre-mix with methanol. Davey claims this change gave an extra eight hp and helped to keep the temperature down (something the early 2-stroke air-cooled racers had a particular problem with). However, to stop the inside of the engine from rusting after using methanol, Davey ran the engine for a short time on regular gas at the end of each meeting.
Most of the 2-stroke racers have a considerable appetite for pistons and rings, and the TD-2 was no exception. The original engine used chromed bores with cast iron rings, but the harsh conditions inside a 2-stroke are not ideal for chromium plating, which tends to peel near the exhaust ports and can cause seizures--especially if the rider is running a lean mixture (see note below).
Note: The term lean, when referring to a 2-stroke, applies to the amount of fuel (gasoline typically) passing through the main jet. A lean mixture implies a reduced amount of fuel which will generally cause overheating (the gasoline also cools the piston, bore and head). A lean mixture in the US is often applied, incorrectly, to a lean amount of oil in the mixture. This would, in fact, richen the overall mixture.
To improve the cylinder reliability, Davey uses modern street bike pistons from a Honda MTX 125 combined with a change to Nikasil coating of the cylinders. Most of his other bike-specific parts come from Meadspeed in the UK.
The stock carbs have been bored out to 34-mm (from the stock 30-mm) and some 30-mm has been cut from the stock expansion chambers to improve the top-end performance.
The stock brakes have been retained as these have proven to have exceptional stopping power and even compare well with another, much later, TZ250 he has.
Davey speaks highly of the Japanese Dunlop tires he has used for a number of years, the TT900s. These tires cost around $130 (AD) for the rear and $120 (AD) for the front and typically last for a season’s racing.
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