Hi..I didn't actually bike around the lake but decided to walk instead. (From Maple Corridor to the Train Station). As for cycling most of the road is traffic free but around some of the bus stops you need to be aware of congestion. Overall though I think you won't have any difficulties. Some of the paths along the river are narrow so being on a bicycle will be OK.

We go by bus, but we didn’t went there directly. We went to our hotel first. By klook or by asking information from your hotel, they have a bus scheduled from Tokyo to the Lake - a part of our bus travel package, early in the morning. They are very strict on schedule. If you avail of the bus, everybody should be on time.

I suggest you just do it on your own, its pretty easy to get around by train, bus or bikes and there is a direct train now from Kawaguchiko to Tokyo. I found everything very well organized in Japan and easy to do things on my own, contrary to what I was expecting before my visit.

It is affected, but you can get there by bus.

The ones that cover Lake Kawaguchiko, Lake Saiko, Narusawa/ Lake Shojiko/ Lake Motosuko area won't cover F-line.

You can take the bus and also by train especially if you have the train Japan rail pass, you only have pay a supplement (if remember correctly BTW 5 to 10 euro per person). We took the train and it was perfect.

Pleasure boat tours, swan pedal boats and sport fishing boats for hire are common in Kawaguchiko. In a few resort hotels, windsurfing is also available for visitors.

In May the only time was morning,

If you are traveling by train, go to Kawaguchiko Eki (Station), and from there, take the local bus directly to Lake Kawaguchico, which costs about 500 yen.

There are coin lockers at the station as others have said but if the ones that would take your luggage are all taken there was also a room with an open luggage area where you could check in your bags for a fee.