My name is Espen ,and i am 48 years old. I am from Norway, but live in Sweeden. I have been riding motorcycles sinse 1982 , but this is my first offroad type motorcycle. I have a 2008 660 tenere that i bought in July 2012.The bike has skid plate,crash bars, aluminium side casas, heated grips, hand guards, mainstand, all original Yamaha parts. I have done 4000 km on it, total km on bike is about 8500km. I love it, but there are two problems for me.

1. I smell petrol when i accelerate and change gear,bumpy roads, and offroad . the smell i think come from the tank lid. I know the new 2011 abs tenere have a different petrol tank with 2. stk air wentilation hoses from the tank. One is directly fron the underside of the tank lid where it have a rubber conection to the wentilation hole from the petrol tank through the tank lid. The 2008 does not have this ,only one hose on the side of the filler hole. Is there something i can do with this petrolsmell ?
2. I get a lot of pain in my tailbone just after 30 minutes of riding. Have anyone tried to take off the seatcover and tried to cut a wedge in the seat to create more space for the tailbone ?
Does a Airhawk cure the problem ?

Thank you for a great informative site, and i hope someone can help me with my questions.
Regards Espen