YS91AC Super charged light usage with Perry pump, setup for smoke. Bearings in great condition, compression is fine. Multiple new/used YS parts included(some can be used on this model YS, and some on others), also included is a NMPES90S 90 degree exhaust which can be used for this engine. Has been stored with mobile 1 to protect the engine, bearings, and diaphragm. Engine ran fine the last time I used it. I lost the YS check valve. Payment through PayPal, USPS CONUS shipping. Sold as is. Getting out of 4 stroke and moving to gas.