The front bumper is the easiest way to tell them apart. the 400 bumper is rounded and the 450 bumper has to straight cross bars.
Here is a picture of my bike which is a 400 frame. <a href="http://www.dirty4man.com/images/ourbike" target="_blank">http://www.dirty4man.com/images/ourbike ... OMBASH.jpg</a>
here is a picture of a 450 foreman front end
<a href="http://www.hondaforeman.com/phpBB2/file" target="_blank">http://www.hondaforeman.com/phpBB2/file ... rs_107.jpg</a>
Here is a picture of my bike which is a 400 frame. <a href="http://www.dirty4man.com/images/ourbike" target="_blank">http://www.dirty4man.com/images/ourbike ... OMBASH.jpg</a>
here is a picture of a 450 foreman front end
<a href="http://www.hondaforeman.com/phpBB2/file" target="_blank">http://www.hondaforeman.com/phpBB2/file ... rs_107.jpg</a>