You will buy your visa at the bordergate.It will be multiple for 90 days against
60 usd. or 45 euros.(AUS)
For the bike, you have to buy Turkish Traffic Insurance if your green card doesn't cover Turkey..Tell it is a motosiklet not to pay more..Price 40-50 Turkish Lira for 3 months..
Turkmen ferry never recommended..If you are lucky enough,you can take it and travel among train wagons ...Azerbayjan side will let you free the first day your Turkmen visa starts...
1-But through Mashad-Iran to Turkmenistan destination is confirmed and approved several times..
2-Second choice is Turkey,Georgia,Armenia then Iran if you like to share narrow roads with crazy truck drivers...
3-Third choice georgia,russia then stans..
Probably you will meet several bikers on the road at the same destination with you.I always help them on facebook to get in touch with eachother while they are on the road..There are several places where bikers at the same destination meet eachother, such as HUB threads, Doug's camp in Bulgaria...
1-Gas(benzin) is most expensive in my country.(second highest price in europe after Norway) .So we started upgrading to cycling
2-Be careful about your visa period for Turkmenistan..Sometimes given 5 days...
Wish you happy,safe,lucky trips.