1957 Yamaha YD-A makes it's debut at Stafford Show 2024
After a very long effort over a long time, the YD-A made it's debut in public after being restored on 12th & 13th August 2024 at the...
Yamaha YD-A Asama Racer approaching completion
At long last the YD-A is almost back together and restored. The last few jobs include making the control cables and finishing the magneto...
Final assembly before paint
So, I've finally finished the building and fabrication stage and am ready for paint. There are still the cables and foot rests to make as...
I know....I know... It's taking so long !
The bike now has its exhaust pipes and starts to look like a bike... Also fixed the front mudguard bracket....She will be finished this...
First Public Appearance with Yamaha
The recently formed YAMAHA HERITAGE RACING CLUB held it's first UK event at Donington Park's Classic Bike Festival on 30/31st July 2022....
Small steps
I refurbed the rear sprocket carrier today. I realised I needed a smaller rear sprocket as the ones I had were for from the Catalina Spec...
Take 2 on the wheels
I finally got the wheels built for the second time, after the re-chroming of the rims was not good enough on the first build, Now they...
The unique identity of this YD-A Asama Racer
It occurred to me that I have not provided evidence which highlight this bikes identity in one concise post, so here are the facts which...
Forks
The front forks were dry built to check fitment. It was a very worthwhile exercise as the chrome plating on the oil seal holders had...
Slow progress
After a long while, progress has once begun again on the restoration. I had become very dismayed and lost a lot of enthusiasm after...
Engine Rebuild
All the cases were soda blasted & vapour blasted to clean and restore them to look as if they just came out of the sand cast moulds....
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...
Frame straightened
The frame was sent for jigging and straightening. It had a bit of a bend at the headstock, but now it's all nice and straight thanks to...
Carburettors
The carburettors are the earliest kind of Mikuni made Amal type. The look very similar to the later ones used on the TD1 range but are...