Well, it's been a while...
Apologies if you were following this blog ! It has been far too long since I have posted any progress on the YD-A restoration. Since the...
YD-A engine confirmed
Upon closer inspection of the crankshaft removed from the engine, it was found that the crankshaft is the correct square stroke 54mm...
Mock up
A dummy front end was fitted as well as a YD1 fuel tank. The machine is now going away to have it's proper fuel tank made as well as its...
Together Again!
With a bit of help from Chip Hellie in the US (who supplied me with the drawings) and Guy Pearson at Exactweld who did the excellent...
YD Racer vs YD1 Crank Shafts
Here I have compared a standard 1957 YD1 production bike crank and conrod to that of a the YD Racer. It is quite clear that the 2 model...
YD vs YD1
The crankcases of the Factory Racing YD-A / YD-B and the production bike YD1 are completely different, when compared side by side. Sure...
Pistons
Both pistons showed catastrophic failure modes ! The top piston ring locating pins on both pistons had become loose and made there escape...
"O" for Osamu ?
Upon stripping I found a small "O" or circle painted on the inner crankcases behind the sprocket. I have no way to be sure, but this mark...
Engine strip
The engine came apart pretty easily and without damaging anything, all that was needed was plenty heat, penetrating oil and the right...
ENGINE !
After a long wait (mostly due to my apathy for reasons undisclosed) the engine arrived earlier this week ! But boy, was it worth the wait...