I have a OS .12 CV-R engine in my on-road car. I'm Pleased with the midrange and top end power of this engine but the bottom end is sluggish. Could this be due to the tuning?? I've found that the engine likes to run very rich... Could this be that the engine may not be broken in yet??? I have at least 10 tanks ran through it.
Does anybody have experience with this engine? If so could you tell me what the best way to tune it is???

Just lean out the low-speed needle a slight bit , 1/16th of a turn at a time. See how it goes. It should probably take just one or two of those and it will be good.

The cv-r is easy to tune and responds well.

Artificial is right on the money with the adjustment !I just ran my racer 2 with the .12 CV-r and it started up and ran great after not running it for almost 2 years. Damn it was fast!