[Galvantula]

OOO did a bang-up job detailing how each Rider's basic powers worked at the start of their series but while I love Gaim I gotta go with Blade here.

Category 7: Metal renders whatever Kouta's 3 Lockseeds can do a trivial matter and having access to lightning and magnetism grants him some control over where he would want Kouta to be (I'm pretty sure Lock Seed armor is made of some kind of metal but it's been awhile since I've seen the show)

Kouta's only real edge is his 3 Rider Machines. In addition to the standard motorcycle he has a hoverbike and a walker mech, although it has been stated Blade is a trained fighter so whatever advantage Prof. Sengoku's vehicles may offer will be trumped by the Blay Rouzer.

It conclusion Kazuma would win, but Kouta won't make it easy for him. The former's victory is in the cards.