I wouldn't use super TT in your DT, that particular oil is mineral based and a very old specification. Go for a good semi synthetic designed for a oil injection system like Silkolene Comp 2 Injector, It's probably a bit dearer (In between 8 and 9 quid a litre) but doesn't smell as bad and is cleaner burning which is what modern two strokes prefer (sounds like Kit e kat
).