YAMAHA Engine Mounting question for differing year models

[jerry_tung]

We are considering buying a 2007 YAMAHA WR450F engine. We used to run the 2005 model but it is currently on the engine dyno. We want to purchase another one to put it in the old car. Does anyone know if the mounting holes on the 2007 is the same as the 2005 model so we can put the newer motor in the car without remaking engine mounts.

[jerry_tung]

We are considering buying a 2007 YAMAHA WR450F engine. We used to run the 2005 model but it is currently on the engine dyno. We want to purchase another one to put it in the old car. Does anyone know if the mounting holes on the 2007 is the same as the 2005 model so we can put the newer motor in the car without remaking engine mounts.

[A. Spencer]

Have you tried contacting Yamaha for a CAD Model of the engine, or inquiring about this?

[Adambomb]

Yeah...good luck on getting a CAD model from Yamaha, I've heard of several decent teams that haven't had any luck with that.

I'm about 70% sure they are the same mounting-wise, thinking they're all the same (externally) from like 2003-2009 or so.

[Simon Dingle]

We made the switch last season and the mounting points are different from '05 to '07. It's not a lot, but enough to mean that they aren't interchangable.

Again, good luck getting anything from Yamaha.

[Simon Dingle]

Oh, the sump mating flange is different too, and I have a nasty feeling that the intake and exhaust mounting is different too but I can't remember for sure.

[RANeff]

The mounts and pan are different, but the intake and exhaust are the same. We went from an 03 to an 08 last year.