Husband and I have been mountain biking in Northern California (SF Bay Area and Tahoe) for 10+ years, and I've been mountain biking for 20+ years.

We are planning on coming in for akimatsuri (Leave ~20 Nov return in the beginning of Dec). We fly into Narita, and plan on spending most of our time in the Kansai (Kyoto and Nara), with trips to Hiroshima and Miagima Island.

So my questions:
- Is it still the season to be riding? We will have JR passes so we'll be able to get around via Shinkasen and JR local and whatever else. Since we're flying into Tokyo, we can go pretty much anywhere. I'm not sure if Hokkaido will throw us too far out of the way, but that sounds sugoi.
- Any place worth renting decent mountain bikes? We once *tried* to rent in Australia in Katoomba, but they rented us crap bikes.
- If there is a good place to rent, can they reverse the brakes so we don't have to run them moto style and end up killing ourselves?
- We can bring our helmets and riding gear, but we probably need water bottles or something to rent to carry water.
- How's the weather that time of year for riding? Rainy? Cold? Snowing? Right now it's 18-20C during the day.
- Any chances of getting a guide? My Japanese is conversational but still limited, and riding signs in Kanji wouldn't be my area of expertise.