I'm not sure which the better way to go would be. I'm wanting to put a big bore kit on my current XB engine (stock) and I have the Zen 25.4cc sitting brand new in a box. Would this be any better than what is in there now? I have the 28.5 in my MT and I love that engine. I'm just not sure whether it would be worth it to put the 25.4cc in the XB? Any suggestions?
http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.4166/.f
http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.4164/.f
http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.4166/.f
http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.4164/.f