I never quite understood the deal with that. I've heard the suit was too heavy, but it barely seems less bulky than Emperor. Later Rider suit designs have been much more bulky than the Kiva suit, too. Was it the materials that it was made from which caused the problem?

I read it was the way it was built. The chest is all one big ridgid piece with not a lot of flex room. Emperor is heavier, but the chest area has more flex and segmentation so it's is easier to move in.

Kiva's suit is a good example of improper weight distribution and design.

I think one of the main problems with the default suit was the chain on his leg though. In some episodes (especially the first one) you can actually see that Takaiwa had major problems to lift his leg.

Yup weight distribution is the major problem with the suit. The chest was too heavy and like Suzu mentioned the chains on the legs caused major problems. Later Suits like Decade are heavier overall but the weight is better distributed.

But it' so cooooool though.

I think Kiva would've been been far less convoluted had they made Otoya the main character from start to finish. Let him be Kiva instead of some ween.

Or have the first act of the series be a prequel then focused on Wataru's generation in the later half.