Yes, you'll find that tires are too expensive to ship unless you MUST. Our method with tires is to pick tires that will get us from one tire store to another!
Also, try to get out of the habit of thinking you have to ship them (anything) from "home" - wherever that may be - and find where the cheapest is from. To Kenya may be from USA or South Africa or UK, (Kenya was British once, so there are lots of flights and commerce between).
It was easy for us to get out of the habit because Canada is a long expensive way from anywhere.
I put a Continental rear tire on in Marseille, but it turned out to be faulty in Tunisia, so I shipped a tire from London, and it wasn't too bad a price. A tire store in London (Chas Bikes) gave it to a courier who took it to the airport and air shipped same day. It was in Tunis next day, and total shipping courier etc was much less than the cost of the tire. Well, maybe not MUCH less, but less.
We run a Metzeler Marathon ME88 120/90-18 on the rear - yes it's a street tire, very high load/mileage design, and it lasts us one continent, even two up, and we run pretty quick on good roads. Even in terrible conditions we never had a problem with traction, the bike - any fully loaded bike - is too heavy to have wheelspin problems. If you were to try the Sahara maybe, but then you wouldn't be as heavily loaded would you -you couldn't be and make it!
Off-road in the mud in Ecuador was no problem either. The one time I ran out of traction was the same time I decided that a serious trials bike was going to be needed anyway! We just chose a different route.
A Bridgestone Trail Wing 101 90/90-21 also did all of Africa for us. That's all around Tunisia, across Libya, Egypt to the Sinai Pen. annd back to Cairo, air to Nairobi, then south through Tanzania, all over Zimbabwe, Caprivi strip to Namibia and Cape Town. And it still had reasonable tread on it.
Tires are available in Windhoek, Namibia, and all over South Africa. If you only need a plain 400-18 cheap dirt bike tire you can probably get them in Nairobi and possibly Harare. 3.50-18 easily, which will do in a pinch, 400-18 or x-17 harder.
Fedex/DHL best for smaller expensive parts that are a lot of hassle if they go missing.
Naturally I buy from local dealers where possible, but sometimes they don't have and it's faster to get them sent in than wait for regular parts shipments. Time is money too, so you have to balance it off at the time.
I carry all the basic standard parts that I might expect to need between good known dealers. In other words, for Africa I carried all the oil filters etc that I would need between Tunisia and South Africa. I use the standard ordinary cheap motor oil from any service station, no synthetic special stuff. I carry a reasonable selection of known and obvious high failure rate parts,and plan on local ingenuity (often very impressive)and my own ingenuity or DHL for the rest if I'm really stuck.
For an old Beemer I can give you a list of failure bits, for other brands ask your dealer what he stocks and sells a lot of for your model!
If anybody wants to give me a list of bits for other bikes I'll put together a spare parts page for the website.
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