BannedCR500Riders.com

boredom set in again so i was looking at a few cylinders laying around. what i was looking at was exhaust width vs bore diameter in %. ive read in bridgeless cylinders, 70% exhaust width is pretty large, maybe going larger is possible if eventhing is done correct but i dont have much knowledge with bridgeless jugs. but with a bridge its possible to go 95% width....100% or more actually might even be possible with a bridge. heres what i found with some of my cylinders:

bridgeless exhaust width vs bore diameter

ts400 suzuki - 65%

yamaha 400 - 68%

bridged exhaust width vs bore diameter

modified cr500 - 95%

stock cr500 - i was unable to get this info. does anyone have stock cylinder laying around they can measure and post the results ????