Tommy, I have the same problem, random cramps in right leg which could come after a few hundred yards or a hundred miles.
I have just last week had endovenous laser procedure to close off a porous vein in my right leg , same way they do varicose veins, next year I am down for a new knee in same leg,I am hoping my recondioned leg will get rid of the cramps
Sounds grim Slappy doesn't it, but we are getting older, all the bits that used to do this stuff happily now kick off and give us stick.
I
am was a brickie and 53 years, laying bricks, rendering, swinging club and sledge hammers and pick axes have all taken their toll on this old boy.
I have crumbled wrist joint, its classed as 'Impact and Rotation' damage, basically the cush-drive in my wrists had worn away and the sprocket carrier is now metal to metal with the inner rear wheel hub. lol!
Wild Plum (Terry) my mate reckons its nothing to do with work my worn out wrist joints, But that's another story