General tips

HEALTH

There are not many things to be considered, except heat during July and August. Sunstroke is possible to happen if being unprotected from the sun. For the same reason, heavy motorcycle clothing is useless during the hot season. The normal peak daily temperatures during July and August range between 28-38 C (82-100 F), while there are some heatwaves ("kafsones" in Greek) where temperature often reaches 43 C (110F). Temperature in islands is always a few degrees lower.

Tap water is always safe to drink in Greece, although there are a lot of fine bottled water brands. However, if you are used to "mineral" (sparkling) water, you essentially won't find it here.

You must be careful when visiting ancient sites or other rocky places. Do not turn over stones or poke your hands in dark crevices or sit on a stone without previously examine it. Otherwise a scorpion may bite you (they are not dangerous) or, if you are too unlucky, a poisonous serpent like "ochia" (viper) will attack you, just because it thinks you are a threat for it. This kind of serpents has a sometimes deadly bite, so the victim must be urgently treated by a doctor.

If you see a flock of sheep on a mountainous non paved road or a sheep-fold, you must be prepared for a possible attack from sheepdogs. They usually only bark and follow your bike for a while. However, sometimes they might really attack so you must always run immediately away of them. A useful hint: if you don't have the time to run the bike, grab a few stones and throw them to the dogs. This is the method shepherds use to guide their dogs, so it is usually effective.

ACCOMMODATION AND FOOD

"Enoikiazontai dwmatia" means room for rent. It is a good idea to ask people in village squares or police stations, if you are desperate. Usually you will see "Rooms for rent" labels.
"Ksenonas" means hospice (small hotel or a bunch of rooms, sometimes in a traditional nice house with kitchen etc).
A room with bath is really very cheap when it costs under GRD6000. I think anything under GRD10000 for two persons is a very good price during July-August in Greece. However you sometimes see much higher prices. If you want to be on the safe side, you must book before, for the most touristic areas (e.g. Monemvasia, Hydra, Spetses or other islands) otherwise you will be strongly disappointed. It is a good idea to ask before leaving the room if there are rooms and hotels at the next target.
In many tourist places people see that you are foreigner and come to suggest you their rooms. Ask for a price indication first, after seeing the room you may start bargain.
If like the best comforts and facilities (being a motorcyclist, you do not care much about that), you must avoid old looking hotels, ones build during 70's are usually of low quality.
Hotel "grading" system in Greece is somewhat different. There are "A" (alpha), "B" (beta), "G" (gamma), "D" (delta) and "E" (epsilon) classes. "D katigorias" (D class) and "E katigorias" (E class) hotels don't have private bathroom and toilet. I think that "A" corresponds to **** stars grade.
Of course you have to check a room by yourself before bargaining.
Since Greece is a country with excellent weather during summer and September, campings exist almost everywhere there is a large beach accessible to the tourists.

"Taverna" usually means a restaurant with meat, fishes and some cooked in oil vegetable dishes. Usually they are fine, although a purely vegetarian doesn't have many choices. Of course you have to avoid the usual "tourist traps" (use your instinct there, although personally I fail many times).
A good rule of thumb is to check if Greek families eat there, our wives usually know how to distinguish the good, clean restaurants from the bad ones.

Unfortunately I am not the most suitable person for giving advises on accommodation and meal (since I do not plan my holidays, I do not book rooms and I am just a person with plain habits).

COMMUNICATIONS

Ferries departure times are relatively accurate, even in high season (June to September), unless there are strong winds. In high season, book as early as possible, particularly at national holidays and fests (like 15th August). Be cautious about securing the bike and do not rely on personnel's good will, at least on the small and medium size ferries.
Mobile telephone network (GSM 900, DCS1800) is available almost everywhere, even at 2000m (do not expect to see it operating at highest summits, of course). If you plan to drive off-road, it might be proved useful.

ATTITUDE

Greeks are pure Mediterraneans. Strongly (and unstably) emotional, selfish, proud, badly organised and impulsive. Do not laugh at them or be ironic (particularly in Crete). Even if they know that many times the services and other public functions are unsatisfactory, they usually do not tolerate critic from foreigners (although they usually strongly criticise those functions). They also do not tolerate a lack of respect at national symbols and monuments.
When in monasteries, it is usually required for the men not to wear shorts and for the women not to wear shorts, trousers and mini skirts.
Police is polite and you will never have a problem with them if you are not offensive or drunk.

FINAL (?)

Always remember that July-August is the worst time to visit Greece because of the tourist peak. Problems in accommodation must be expected, so avoid to search for rooms in the night. Many villages and towns have hotels, rooms, traditional hospices (like those in Mani, par example) or campings, however, tourists are so many that service and accommodation is many times not the best. The highest peak occurs around Greek (orthodox) Easter and around 15th August.

But even so, there is no need to worry about. Greeks are typical Mediterraneans so they usually feel easy and carefree (at least when they live away from the big cities). I hope visitors feel the same way when they come in Greece. Free, simple and emotional. Like the traditional Greeks !