Shares of Harley-Davidson  (HOG) rose 6% to a three-month high on heavy volume Tuesday morning amid trader speculation that the motorcycle maker could be the target of a leveraged buyout from private-equity giant Kohlberg Kravis Roberts.

While the markets buzzed about the possibility the company could be taken bought out, KKR was mum. “We never comment on deal speculation,” Peter McKillop, director of corporate communications at KKR, told FOX Business.com

Harley-Davidson spokesman Bob Klein said, “We don’t comment on market rumor and speculation.”

Still, the motorcycle maker’s stock gained 6.98% in recent trading to $28.35. Earlier, it hit $28.46, its highest level since Dec. 8. Harley-Davidson’s shares have surged 137% from a year ago.