It wouldn't be hard for me. - Only one 18650 is no way gonna do 900lm for 2hrs, even with a 3400mah cell.
Not only that, but it even comes new for 2015 with a XML, an outdated emitter:-(
Also, the way that thing mounts to a handlebar is less than ideal too. - I have seen many Cateyes with that sort of mounting stripped out. - The Fenix appears to be much stronger.
Thanks,
-Chuck