The TD1c based on the YDS2 street machine, a twostrokes parallel twin cylinder with piston ported intake.

The TD1 model had only modified cylinders and heads, expansion chambers and modified carburettors, which brings the power on 40 hp at 10.000 rpm. and a weight of 95 kg.

The TD1c followed up in the spring of 1969 by the TD2 and is all over Europe available. The TD2 has from than also a bigger brother namely the TR2, based of the standard 350cc YR2.

The TD2 produced by then 44 hp at 10.500 rpm. and has a bore and stroke of 56x50mm, whereas the TR2 is give up for 54 hp at 9500 rpm. and a bore and stroke of 61x59, 6mm.

The machines goes like hot cakes over the counter, and Kent Andersson is one of the first owners of the new TD1, he wins 2 GP’s and stands seven times on the podium in that year.

His win at the German GP at Hockenheim in May 1969 is the first of many GP wins of the made by the TD and TR production racers.

But that year The Australian Kel Carruthers on the Benelli four cylinder four stroke is superior to him. Rod Gould finished three times as 2^nd after Agostini on the MV-Agusta in the 350cc class.

1970

In 1970 the 250 and 350cc classes consist by 75% of Yamaha production racers, which are in the right hands growing to real winners. The Yamaha machines are at that moment the best there is on the marked, what is showing by his enormous succes over the whole world. Yamaha meant at that moment as the ultimate two-stroke expert in the world.

1971

In 1971 the new TD2b production racers are modified as the factory bikes of last year, namely with the upraised exhaust port and shortened exhausts. But all the top riders must buy electronic ignition by themselves, and there were still only 5 gears on board.

Rodney Gould and Kent Andersson are equipped with full factory racers. The season starts with minor modifications on the YZ625 and YZ631 machines regard to last year.

But from Assen the new machines are available, the 250cc YZ632 and the 350cc YZ631, it were the pre-production machines of the TD3 and TR3 for next season.

The air-cooled 250cc YZ632 has electronic ignition, 34mm carburettors, 6 speed gearbox, a dry clutch and a bore and stroke of 54x54mm.

The output is about 52 hp at 11.000 rpm.

The 350cc has the same construction as his little brother, the bore and stroke are 64x54mm and an output of about 63-64 hp at 10.500 rpm.

The picture on the left is Rod Gould while testing in Gaydon the prototype TR3 production racer. Also there were some disc brakes tested. Pay attention on the front frame tubes, they contain the radiator brackets already, watching the things to come.

During the Assen TT a water-cooled engine was built up, but there was no time to test it for the Assen GP. The plan was to use two water-cooled engines for the first time at Monza, and in the Spanish GP if they were reliable, but it didn’t happen.

The new engines are not exactly much better than the old YZ625 and 632, but with the new frames, electric ignition (Femsa) and the dry clutch, they are on the whole line just a little faster. In Goulds opinion the new engines gave far better power output in the 7000 to 11.000 rpm. range than the TR2.

The completely new built machines are different to ride, that’s why only the new bikes were raced from Assen

The frame and engine are directly based on the street DS7.

The 250 and 350 engines using now the same crankcases and gearbox, and also the frames are identically.

In the 250cc class Rod Gould has a good season, but also because the development works on the new models he has to acknowledge his superiority on Phil Read.

After the Ulster GP Gould had to workout the last two GP’s without his mechanic, Randy Hall. The American had to go home to prepare the introduction of the new production racers of next year.

This development had great impact on the team and the results; with as all time low his fall out in the last GP in Spain, what did cost him the world title.

	The sensation that year is the return of Phil Read, now as a private rider after his career in the 60s years as a Yamaha factory rider.   Phil comes well prepared at the start, with his own complete modified TD2. He announced in the previous year he wants to get the world-title with his own material, and with little sponsoring of Castrol. Read rode in 1970 with success races in England and also some GP’s at the end of the year. Because of the good feeling and the success of the production racers he decided to return into racing.   The machines are basic TD/TR2b models, which were carefully prepared by his mechanic Ferry Brouwer, and by Helmut Fath fitted with a dry clutch. The engines be housed in a Cheney frame from Renolds 531 tubes, and further provide with double disc-brakes at the front wheel and a single disc behind. Also the engines were equipped with a Quaife 6 speed gearbox.   This transformation of the TD2b and TR2b was enough for Read to win the 250cc world title, the first world title won by a private-rider.

(photo: Bernd Fischer)

In the spring of 1972 the 250cc TD3 and TR3 production racers are available to anyone.