I also could not afford Ventura but I recently did 3,000km in 2 days on my 748 SPS travelling from Istanbul to London and used a combination of a tank bag and an Oxford tail-pack on the tail section of the bike. Provided you put some sort of baffle between the tailpack and the seat unit your paint will survive. I used rubber table-matting; worked a treat. With plenty of bungess from the tail pack to the footrest hangers it was rock-solid.
The only problem with a tank bag is that it prevents you from getting close to the tank and thus limits effective top speeds to c 160-170kph unless you have a strong neck !
if you dont have rear pegs, ie not a bip, then tieing down is also difficult. I looked at doing this with a tail pack I have and, regardless of potential paint damage, there is no where to bungy them down.
29-Sep-2006, 10:33 
Hybrid Mode
