In Almaty you would find tyres at the Yamaha dealer, they can be pricey and you take what they have, not neccesarily what you want. There is also the Bike club with no name behind the "hilton" or some other flash hotel. It has an old bike on the roof. The guys there should be able to help you out with a fix, any local biker will know of it.
In Novosibirsk NBS bikes are great, they have good mechanics, great workshop and import Jap bikes second hand. They should be able to help out.
Close to Antarctica and a long way from reality