I found these cyls just wondering How they were setup
http://www.x-h2o.com/threads/104857-Yamaha-Superjet-R-amp-D-NON-Powervalve-850-cc-cylinder
http://www.x-h2o.com/threads/104857-Yamaha-Superjet-R-amp-D-NON-Powervalve-850-cc-cylinder
I am running the cast Lamey cylinders and I don't THINK there is enough meat there to bore big enough for the 89-91 sleeves. I may be wrong tho.question for Brian or Tricky.