It is possible.

As mentioned you should have all the paperwork related to the bikes, with the bikes.

For good orders sake, I would also take along passport ID page photocopies of the registered keepers (the people on the V5 documents).

You should also have a dated and signed letter from each owner (signature matching that in his passport, name matching that on the V5) saying you (or whoever will be the driver will be at the border) have permission to transport the bikes from the UK to Mongolia across Russia.

It should be enough to have it in English. It used to be compulsory to have it in Russia, officially translated, but I believe the law changed earlier this year. It may be wise to still have it all translated into Russian, even unofficially - border people will have english speakers, local cops en route will most likely have none.

You will also need the similar letter for whoever is driving the van, if the van is not in the name of the driver.

You will also need similar effect letters for the trip back (as it will be a different driver) for both the van and for the bikes.

Do yourself a favour and cross at the border from Latvia to Russia, as they are likely to give you a lot less hassle that if you try to enter the Customs union via Belarus.

If you want to drive a van from UK to Mongolia in a week, you are going to have to be at the wheel at least 18-20 hours a day, or maybe even 24/7 ... just rotating drivers while the other sleeps. Its a long way and the two in the van will be truly shagged when they arrive. The smart guys in your group will choose the drive back. At least they will be fresh for Mongolia.

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