I recently acquired a 1976 RS 100C with less than 5K miles.  It doesn't need much attention, but I want to replace the tires.  The bike came with a 2.5-18/front and 2.75-18/rear.   The Owner's Manual says these were the proper tires, but my Haynes Workshop Manual says 2.75-18/front and 3.00-18/rear.  Can anyone tell me which is correct and/or recommended.  I'd like to stay as close to "original" as possible.

Thanks,

Bob

not sure of this helps:

https://bikez.com/motorcycles/yamaha_rs_100_1975.php

looks like haynes is wrong.

 

Thank you.  I was thinking the tires on the bike when I got it were the originals (very bad shape), so I'm going with 2.5-18 and 2.75-18

 

Bob