Home Race Bikes Works racers Yamaha YZ623, 125 ccm
Yamaha YZ623, 125 ccm

The factory YZ623 ccm twin cylinder racer developed from the 1969 AS1 based model up to the latest 0W15 twin in 1975.

The 2 pictures from the early 1969-1970 version show clearly the combination of standard parts and factory specials, like the wheels/hubs. (You can "click" picture 2#-3#-4#).

 

Yamaha YZ623, 125 ccm 1969-1970
Yamaha YZ623, 125 ccm 1969-1970

 

On this picture it seems that even the standard AS1 rear shockabsorbers are fitted!

 

The "C" model from 1972 has already improved a lot, with the new bore/stroke of 44x41 mm instead of the old standard bike 43x43 layout. The gearbox is now 6-speed, Watercooling is added, a dry clutch, VM28SC carburetors and a double twin leading shoe front brake made it a very good bike.

 

Here you can watch Ferry Brouwer working on the Chas Mortimer bike during the Swedish G.P. of 1972. It looks like it was a scorching hot day and paddock conditions were very, very different from today's luxury.......!

 

The frontbrake as fitted to the YZ623 here is the same as later on the TA125, a reversed DS6 brake drum with a CS3/CS5 right hand brake plate. This brake was exchanged for a proper one on this Dutch bike by Ferry Brouwer the week after this picture was taken (see link with early Dutch Team)

 

Yamaha YZ623, frontal view
Yamaha YZ623, frontal view

 

 

Yamaha YZ623, left engine side
Yamaha YZ623, left engine side

 

Yamaha YZ623,

 

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