Laos Border requirements:

Passport, 6 Monate expire later then 6 month, min. 3 Pages free

Re-Entry

Green Book original

International Driver’s Permit or Thai driving Liscense

2 Passphoto

4 Copies Passport

4 Copies Green Book

4 Copies Greenbook Taxpage

E Visa, https://laoevisa.gov.la/index

Departure Card ausfuellen (Aufenthalt Laos)

Visa 40 Dollar at border 30 Tage

Motorrad kann 14 Tage bleiben, Verlaengerung um 14 Tage an Grenze moeglich

Sticker 3 Dollar at Border

Laos Insurance 300b at border

Tour Permission from Traveloffice (Around 1000 Baht) Not required, but they want
The Tour permission you get at the border from Travel Agents or you find somebody in advance

Look for Arivel stamp and if the Chassis number same in the Import paper

If the bike is not registered in your own name  in Thailand, or a rented Bike you need a Power of Attorney

If you are more then 3 drivers you need a permitted Tour Guide