Here's a more detailed look at the Ascot's YDS2 based motor.....

I have removed the clutch from the end of the crankshaft and transmission drive gear....



Notice how stout both the crankshaft and transmission shafts are..... with the clutch assembly weighing less than the appx 8 pounds that a DT/RT flywheel weighs...

I seriously doubt you could snap the end of the crankshaft on one of these motors?



This motor appears to be very very well built looking at the parts I have accessed so far !

Here's how that side looks when assembled

Check out the very cool Speedo/Tach gauge for a 1963 YDS2.....
I think it a year only gauge?



Gotta love the right to left swinging tach...while the speedo swings left to right on top



Who needs a redline.....when your tach goes to 14K ?

Kinda like guitar amps that go to 11.....cool as hell!

Lookin good Super Dave

Gotta love the last two digits of your ODO

think these have the flat rotary cam plate underneath as remember adjusting the stops on one at work which was either a YD2/3 or actually think was a YDS3 in hindsight but mutch the same horse i suppose. YD3 was a neat ride to work type bike by memory, single carb & all that. YDS3 wailed from inlet noise & went like hell. Now that reminds me--back in the day we were coming back from a road race & found a Guy & girlfriend stopped on the road with a YDS3--flat battery, so he took it out & we put it across the car battery & gave it a boil up for a minute as 6 volt in those days but 12 volt car. Can't quite remember what we did but might've put a screwdriver into one of the cells to get 6 or 8 but probably not--in a hurry. Anyway this worked for about 20 miles at a time--100 miles home. Next day--he worked around the corner for the opposition shop--said guess what was going on!!, he had fitted the battery back to front which was the problem all along. No blown fuses as i recal. Couldn't get away with that on a modern alternator system. YD had the old brush generator in those days. Actualy 'i said' 6 volt but could i be wrong?. Was wrong once--just can't remember when lol.

That speedometer looks familiar, I know I saw it on another bike......but what bike ?? just can't put my finger on it Dave.....

Dave,
That is a glass (not plastic) window, right?

It is plastic.....Deet.

Pretty good condition considering it's over 50 years old ?

That is amazing.
Glass clarity will outlast plastic. I would assume this would be the governing requirement during development.
But knowing how difficult it would be to mass produce the glass with a precise hole for the trip knob, would they consider plastic?

Very interesting....

RT325 you have quite a good memory and I like your stories about these old bikes. Yes it has the rotary flat cam
underneath. It's great fun studying and working on this great old Yamaha ! Fortunately I have some of the "rare bits" like the TD1 aluminum cylinders and high compression heads the Ascot came with !