Hiya Rocket R.,
Ta for that, I've been measuring every which way, could've measured me way to the moon(in microns). I bought new collets in UK back in '81, but they didn't fit then, so I (think I) figured something was amiss,no ready available info, but the 'too hard' basket was handy.
When I bought new SR V.springs last year and I checked them for length- ok(I think, and will again), but not dia.
,<-not a problem just a head banger! , something still didn't twig, and I dug out the collets again, but decided I must've got'm(2 sets ) for the M20 that I had a bit before then ! so- back in the 'hard basket' ?
It wasn't till I cleaned head up to reassemble, that I realized the collars I've been using were too small (ie totally wrong),and with research figure the new collets from'81,....surprise surprise (should) fit new collars!!!!! , However- have been checking/measuring the valves "every which way" again mainly the collet grooves, and the 'new' collets don't quite seat in there properly, so'm going to do a bit of 'dremel engineering' on them(collets). Kind of hard to explain, but they just have ridges round the inside just under the engaging 'lug'(see photo), and figure they should sit snug on the valve stem, not rickety rockety(nothin' wrong with rockets in the right place), as I figure it'll put extra pre-load on the springs if they sit too 'fat'??
Thanks Rocket and also KiwiGF I had another look at your story,useful but already covered. Cheers duTch (did this last night and left it,hope makes sense)
NB I never thought I'd get so involved in this -was supposed to be a pull it apart and ride in a couple of weeks