Hi guys,
Recently purchased this as a first bike for $500. It had a few issues but dad has fixed it and has put on a new reg/rec, stator, new wiring etc.
She goes perfectly until she hits about 8,000 revs in 5th or 6th gear, then just surges for a while until she gets to 12,000 revs, then goes perfect again. She also gets extremely hot very quickly (so much so that i can feel it under leathers).
Any one have any suggestions?

Thanks