I just bought this bike about a week ago and every time I pin it in 5th gear she dies about 20 seconds after doing so. When it cuts out, it dies completely, can't jump it or kick it over for about 5-10 minutes. It only happens in 5th. Engine was rebuilt about 8 hours ago (top and bottem end), compression is fine. Just had everything serviced, including fresh oil and coolent. Seems to hesitate a little bit in 1st and 2nd but it isn't to bad. I was reading around, and i've got 2 ideas as to what it could be, either overheating or a bad cdi box. I can't see it overheating, as I am riding in weather thats almost 0C (or 32F), and the cdi box was replaced about a year ago. Any idea as to why this is happening? When I try to kick it over right after it dies, there is little to no effort to kick it over. I have to wait a bit of time for it to be able to kick over again. Once it kicks over, she is perfect.