I believe there's gotta be some out there. Ive been meaning to look around for some as its also a good way to get some reading practice in while looking at some nice bikes. If you can read JAPNZ, I would think that Mixi would also have some stuff as well.
ATM the only thing I can think of is PedalMafia
I have been surfing around and found many stores are looking for English-speaking crews. Just wait around a bit, you might find English forums. So far I haven't find a place truly dedicated like this site. I am sceptical of places like Mixi and blogs. I think I am being too old-fashioned or something.
Are there any independently hosted forums? I don't wanna be reading diaries.