My fiance has an '02 954 and it pops out of gear usually in the morning when it's about 20 degrees outside. From what I can tell this is common in such a climate with that cold of weather and trying to drive right away. However there has been a "stuttering" sound coming from the crank case. I'm thinking that the gears are going bad? What we know of previous handling is that it was ridden hard for the first three years and apparently not very well taken care of. Any other ideas?