Originally Posted by fischer550
I looked around ebay and I could not find a single 40mm stroke engine, even the few straight heads all said 38mm
go here to this link and scroll down you will see the lowers I run built and run on two of my bikes so far and I have another just waiting to come together, smoothest and best performing engines I 've run hands down. and these are 40MM stroke engine lowers for $69.99 + shipping
Neil aka ( motorbicycleracing ) here on forum also sells these lowers and complete engines he calls his GenV engines, he sells his cheaper than dax and does his sales with money order or check, great fella and he will help you out any way he can.
here is a link that will take you to one of neils threads that you can use to click on his username and send him a private message if you are ever wanting one of his GenV kits, engines or Lowers.