This is my Nitro elements Artattack 1/4 scale diesel sled.
OS RFB .21 converted to Davis diesel. This is one of the best conversions to diesel I have ever experienced! As a glow........there was just to much drive train load on the engine. As you drove it longer, the more the drive train robbed the engine of power......and soon would overheat and shut down.
There wasn't anything to change as far as gearing, it is a fixed 4:1 ratio. The conversion to Davis diesel was the ticket! I can run this engine slow and it pulls the sled like a dream! I have had it clocked at 41 mph with very cool running temps and very reliable!!