I know the aircooled belts are 12,000 miles - or 2 years, whatever comes first.
AK picked up one of the engines (now in his 'monster special bike') which had new belts on but the engine hadnt been run in over 18 months, so he changed them as a matter of course.
note: they looked fine, the tension was fine... when he removed them, they were just like Henners ones
rather out of shape
C
[Edited on 13-6-2005 by CK and AK]