Hi - My VTR250 has been having a few issues taking off from a stopped position. It revs very high before it will start moving, and then I feel like I need to push it off with my foot. I've noticed this only after the bike has been running for a while and is hot. I've dropped it off at the workshop and the guys said that they couldn't find anything wrong. It's done about 10 000Km. It runs fine in all other gears once it gets going. This seems to be a bit of a recuring problem. The last time it happened was around the 6000km mark and the guys in the workshop told me to change from premium to regular unleaded and this seemed to do the trick - for awhile. Any ideas?