I know the sound of noisy bearings in a manual tranny, that whirry kind of noise. Do TH700's make a similar sound when the bearings are getting a bit past their best?
Hmmm those manual gear boxes for old vn's wer neva made to last. mine makes a rattling noise, has for the last 30000km neva gave me a problem. my last manual gear box did the same. If u go to ur local autoparts shop they usually sell an additive u can add in with ur gear box oil, makes it less noisy and should do it some justice. while ur there u marz well change ur oil