After x-rays and blood tests they now tell me I have Polymyalgia Rheumatica,

This weakens the muscles in legs and arms and makes them ache a lot like when you have flu.    However, good news is it is treatable with steroids and I have started a course of treatment and results so far are very good and I am now spending a lot more time back in the garage rather than the house !!

I should be back working on the bike again very soon.

This is all very good news as a couple of weeks back, my wife was having to help me dress. So here's hoping that the cure is permanent.

Mike.

Good to hear you're on the mend Mike , hope all is well in the garage too !! Ken

There is a high precision fit between the piston and piston pin in several aspects. It is way better to make a connecting rod bushing than modifying the piston for a custom pin. So the piston should be used with the pin supplied with  or made for, and the rod bushing modified to suit the pin.

Pin is better to be bought finished from a reputable piston maker if not provided with the piston. Making one is hi tech stuff in metallurgy, heat treatment and surface grinding. Both outer surface and hole surface has importance in fatigue failure, and to get the right stiffness with the lightest weight possible takes some knowledge.

Broken wristpins isn't common because they are overengineered in almost all cases, but wrong material, heat treatment or grinding finish can result in breaks or heavy wear in piston pin hole.

I have had problem with bushings that nipped the piston pin and when that happend the pin looses it function to float back and forth in the piston. In one of my engines it probably nipped up then released and nipped up again in different positions. That made the pin pound on both pin locks, widening the grooves almost to the brink of them jump out. I heard the engine didn't sound right and didn't feel right so I removed the cylinders and that saved a major breakdown. In another engine I discovered miscolour at the smallend and black soot at the piston underside. So I advocate loose fitting at the pin bushing. I haven't measured the play exactly, I ream with an adjustable reamer now so the pin fall or runs through the rod without effort even lightly oiled with thin oil. Of course I would get a smoother surface that may improve the longevity if I could hone the bushing as a last step, but I haven't got such small hone. Yet.

With hands, try picking some stinging nettles, see if that works. Strong anti-histamine anti-inflammatory, works great for my knees. You get used to the stings very quickly.