I've done this before and people seem to like my lists. Let's get to it. Here are my top seven favorite Kamen Rider theme songs.
7. Alive A life [Kamen Rider Ryuki-2002]
It was between this or Kamen Rider Agito to be the lesser bookend on my Top 7. I *HATE* the show, but this is definitely one of the best theme songs to head up a Rider show. The first few seconds are kind of lame, but once the song gets going I love it. It's a great beat with some nice pacing. It also helps that it is sung by the great Rica Matsumoto.
6. Kamen Rider Kuuga! 
This song is great for a few reasons. For one, it marked the return of the man with the mask and motorbike. It also has a somewhat retro feel with the guitars and elements. There is a good reason for that... This song plays sliiight homage to Pink Floyd's Welcome To The Machine [Listen to it a couple of times to pick up the "borrowed" elements, mostly around the 2:40 mark, also 6:23]. I mean it's pretty obvious, but it isn't really a total ripoff. Not quite BSTTF material...but maybe I'll revisit it in the future. Such a kickass theme song.
5. Round ZERO~BLADE BRAVE [Kamen Rider Blade OP1-2004]
It's only natural that I also like this song. It is an incredibly catchy tune and very upbeat. Great singing. What else is there to say? I really liked this song for whatever reason.
4. 輝Kagayaki [Kamen Rider Hibiki OP1-2005]
Fun Fact: This song chills me out when I fly. I hate flying. I'm not sure why this song relaxes me on a plane, but I'll take it! It really is a beautiful song no matter which version you listen to [or if you listen to the "Full" version which is just all of the variations linked together]. I absolutely love the direction they went with just using an instrumental piece instead of a pop song. I truly reserve the word "Epic" for Oceans, Deserts, Canyons, and, well THIS...but kagayaki is epic.
3. Kamen Rider BLACK RX 
Here comes the nostalgia. Kamen Rider BLACK and BLACK RX were my first Riders. I was a kid and the idea of waving your hands around using a belt to unleash your inner kaizo ningen was amazing. I love both shows equally, though I wish they would've subbed Kotaro out for a new character in RX.
Oh right, the song.
Well Tetsuo Kurata did such a lame job on the Kamen Rider BLACK theme that they brought in a pro for the sequel. Takayuki Miyauchi. I genuinely think that this is the song that cemented his place as one of the greatest Tokusatsu singers ever. Remember, up to that point he'd done most of the Bioman songs, some Flashman songs, and a Shaider song. He was always a great singer and really didn't bring anything new to this song, but his style was juuust right. Paired with a serious and catchy beat, this song is the Reese's Peanut Butter Cup of Kamen Rider themes.
2. Let's Go!! Rider Kick~Hiroshi Fujioka vers. [Kamen Rider-1971]
I am a little picky with this one. I only really like the original Hiroshi Fujioka version [the 2000 one he did with Rider Chips is also acceptable-ish]. I couldn't quite get into the Masato Shimon version. Infact, I don't really like Masato Shimon's singing
Hiroshi Fujioka is not a singer, he's is a mountain with a digestive system. He did a pretty good job on this song. The music is like most late 60s, early 70s children's television theme songs, so ofcourse it has a good rhythm. I will take this theme song over any others from the era. It's fantastic.
Oh, and I have to mention Segata Sanshiro. We all know the story...we all fear the man. The only people who don't fear Segata Sanshiro are the record label. The Segata Sanshiro theme that plays during the commercials is not sung by Hiroshi Fujioka despite the fact that he recorded a version. Once again, people are messing with the wrong guy.
1. Moero! Kamen Rider [Kamen Rider/Skyrider-1979]
What is it about Kamen Rider that it is so damn awesome everytime it has a rebirth? This was the first time 'Rider came back after an absence and it turned out to be one of my favorite Rider series. The theme song is, however, my favorite full-stop. Ichiro Mizuki! Backing vocals that don't suck! GREAT music! It's not even a case of me not fully understanding why I like this song. I know this is a good song. This is a song for a superhero who can fly. It's big and it's majestic. It's full of action and it's just well made. This has it all.
Honorable Mention: Ai ga tomoranai [Kamen Rider ZO-1993]
I figure that I will mention this because when the hell else will I be able to talk about it?
The Kamen Rider ZO movie didn't have an opening song, it just featured some kickass score over the title. It did, however, have an ending song. It had a new sound that was lacking from Tokusatsu songs. This song might even be responsible for the JPOP creep in to Tokusatsu song collections. This song felt like the first Tokusatsu song with serious production quality. Well, besides the Turboranger songs--they sounded very rich as well.
It was nice to hear such a quality song in a Tokusatsu movie. As a bonus, the song itself is pretty killer. It reminds me of a cold, rainy day in the wood [which I happen to like].
All-in-all it's amazing that nearly half of my list is made up of "avex" era Rider themes despite the fact that avex mode seems to be in the business of pumping out music to shit to. Things were better in the Columbia era [Agito was the last series to release music under Columbia], but maybe a little too predictable.
If you want to check out my other Top 7 lists, go for it!
Top 7 Sentai OP themes
Top 7 Sentai Mecha themes
Top 7 Sentai Suit designs
Top 7 Metal Hero OP themes
That's all for now. I love this list...
See ya next time!