CRF450 Engine Swap

[petersonracing]

Anybody done or know someone that has done this swap into a stock 250R frame? I would like to see some pics and get some info on what needs to be done/changed just so I know what to expect. I have an '86 R and have been thinking seriously about doing the swap if it is possible to do it successfully. I have full access to a machine shop and just about any tools you can think of so no problems with that. I also have an extensive mathematics background to aid in fabrication. I ride MX and freestyle. Any info would be appreciated!

[nacs400ex]

I believe you are going to have to do a lot of chopping. I read before the engine is too big to be fitted in the stock R frame. You have to raise the top frame rails. I have never done it so I dont have personal experience. I wanna buy an aftermarket frame, and do the swap that way. Way easier.