11.3-1 stock piston with stock 3 layer base gasket
The stock compression ratio for a 2003 Yamaha YZ85 is approximately 8.6:1.
8.5 to 1 compression is factory stock.
The stock compression ratio for a Suzuki QUV 620 is 10:3:1. Special spark plugs can increase that compression and the horsepower.
It is 8.54 ~ 10.12 :1
8.3:1 is stock
398 cc base
9:1.
The stock compression ratio for a Can-Am Outlander 800 is typically around 10.8:1. This compression ratio is designed to optimize performance and efficiency for the ATV's Rotax engine. Modifications to this ratio can affect power output and engine behavior, so any changes should be made with careful consideration. Always consult the manufacturer or a professional when making modifications.
8.5:1 stock
6 to 8 degrees advanced. for stock compression ratio.
your answer is not easy. do you want ratio or compression pressure. I would guess you are talking pressure, which on a stock engine is around 155 lbs.
stock compression on a ka24de found in your 91-98 Nissan 240's is 178 9.5/1 ratio