OK 650 cc is a volume (ala Motorbike engine displacement)
.. for clarity industry standard ETRTO numbers for bead seat diameter is better..
(middle of the brake track)
571 mm imprinted on the tires ? that's French 650C ,
A is 590, often on 3 speed bikes
B is 584... now Aks 27.5 " in MTB lingo now ..
regular 26" is 559... 2nd number tire width like 559-47 (26" x 1.75")...
....
Last edited by fietsbob; 04-30-19 at 08:45 AM.