Model A - crankshaft shock absorber 1

 It's all go here. The latest investigation is to look at the crankshaft shock absorber, which it turns out is missing a few vital parts!

These are the sections of the parts book that deal with the crankshaft shock absorber. I had assumed, wrongly, that because there was a shock absorber in the clutch there would not be one on the crankshaft. However club member and black Ariel spares coordinator Lee, who is currently restoring a 1928 Model E (which has a Burman box) tells me that his bike has a shock absorber in the clutch as well. Therefore I am now given to believe that all the bikes have a crankshaft shock absorber.

I'm missing the spring and both the collars that it sits in. I'm told that a Lambretta spring maybe useful and I have a dimensions for that and I actually I have ordered one. 

The spring collar A6/714 is missing and I have no picture at the moment. However the function of these parts is fairly obvious so I'm confident that I can make something up.

This is the bit that Sturmey Archer call the spring retaining collar. It's listed at Draganfly but unfortunately out of stock at the moment I'm sure we can make one of these.

This is the A6/712 sliding member:

As you can see, the spring sits on a 33 mm diameter. The Lambretta spring dimensions are:

• Free length = 37.5mm
• ID = 35mm
• Wire dimeter = 6.85mm

The diameter should fit nicely. It looks like this:

As you can see, there is only two wire diameters in that 37 mm length, so it should compress considerably - maybe to the 20 mm I have available!