Speedster motor swap

[Gary pope]

Just checking to see if anyone on here has ever tried to do a motor swap to go from the 657x 2 stroke to a 4 stroke motor and if so how much work was involved in it? I mean I know I can just drop in a 720 motirbin its place but I'm thinking about switching over to a 4 stroke motor if it won't be too much work.
Give me your thoughts.

 

[dmiles]

Following this one, interested in this myself.

 

[jhjesse]

IdoSeaDoo did it. Below is the thread:
https://www.seadooforum.com/showthread.php?69006-Challenger-4tec-Upgrade

 

[dmiles]

Holy fabrication Batman! Not exactly plug and play! Great reading though.