Originally Posted by
tubehead
I've been out of racing for a few years now and went last weekend. I threw a rod in my S7 and I'm looking for a new RB. I've read several pages back in this thread and had a few questions. I noticed that RB is going to stop producing square stroke engines, whats the reason for this? I liked the power of my S7, it had been worked on alittle but it was very drivable. Is the S9 basically the same engine? I'm running it in a RC8 with a 2035 pipe. Is the Cross 10 replacing the S9? Thanks for the input.
Well I am not exactly sure on the reason for eliminating the square stroke engines but it could be that they are just old technology. Novarossi doesn't have any more square stroke motors so maybe it was an extra cost for RB to keep these engines in production as they are the only engines with 13mm cranks.
The S9 that is still available in some shops is the same as the S7 you are running. The WS9 will be an even better choice if you like your S7, the WS9 will have a little more power on the bottom end and more top end than what you have now but it will still be very smooth and very controllable.
The Cross10 is actually replacing several engines, the S3/Junior9, S5/Hobby9, S7/S9, WS7/WS9 were all square stroke engines and they are all going away. The Cross10 is the Novarossi based replacement for these engines, the K9/K10 is the Taiwanese engine in the lineup that is designed to give a good performing engine at a good price. (I personally prefer Nova quality)