classic motorcycle forum

OK here I am, 50+ and looking to get back on 2 wheels after a long absence.  Question is "onto what?".  I'm very tempted to go for a pre 70's A65 beesa, but would like some impartial advice about the great crankshaft issue.  For non thrashing use is the drive side support adequate or must one sensibly go for an SRM type mod with ball and roller bearing conversion?  If I do, what effect could this have on the value [origionality] of say a Spitfire III or IV ?   The opinions I've had first-hand are polarised so I would like your views.  Take it as read that the motor will be rebuilt with "sensible mods" such as an upgraded oil pump and a belt drive/needle roller clutch throw out bearing.  

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