what parts are interchangeable on a 400ex and 450r

[Hondarider440ex]

what parts are interchangeable on a 400ex and 450r like the thumb throttle cover, brake resevoir cover and etc....... because blingstar has new products out but they only make them for a 450r

[otis416ex]

I know the front brake lines are interchangeable and the steering stem also works with some slight mods to the brace by making spacer and using some longer bolts. This is because the 450r has a bigger stem.

[CSR400EX]

front bumper, front spindles, some air filters, hubs. thats all i know to add