Ilias,
I went to the Stans, and one thing for sure, it will be impossible to find 21'' tyres. They just don't have any bike with that size. 18'' my be possible, depending on the size, I'm not sure, but better carry some with you (major hassle, I know!).
Oil is available everywhere if you're not too picky about it (you shouldn't). After all, Urals (Russian bikes) use massive amount of it..
Petrol is generally not an issue if you're not too picky about the quality. In the most remote parts of Kirgizstan/Tajikistan you'll buy some on the road side, what they mix in is anyone's guess but the octane can get as low as 76, this added with the altitude will be your biggest worry .
For range, 700km will get you through all of the Stans easily, I guess the longest stretch would be in the Pamir Highway, maybe 500km.
Have fun!
Laurent
|