Hiya Charlie,
You didn't say if your bike is fuel injected or has carburettors? Are the petrol tubes disconnected from the fuel tank or the engine (carb)? If the tubes are off the carbs there will be what look like brass nipples exposed on them.
The fuel lines can really only go back on one way because of their different thickness & the location of them on the bike.
There should be a big & skinny tube coming from or going to the on/off tap on the petrol tank, any others will be either breathers or overflow. The big one is your fuel line & the thinner one is the vacuum tube. You might need to take the saddle off, loosen the petrol tank (don't remove) & lift it up on the bike to get better access & see what you're doing.
Hope this helps....
Steo, November 2009
