NEW YORK (TheStreet) -- Shares of Briggs & Stratton  (BGG - Get Report) are up 5.2% to $21.07 in afternoon trading on Tuesday, continuing the stock's 22% year to date spike.

Shares of the Wauwatosa, WI-based air cooled gasoline engine producer were at $15.81 on January 15, the day after it introduced a new inverter generator to the market. Since then the stock has risen about $5 to its current level. 

Following that announcement, the company on January 20 reported its second quarter earnings results. While the stock temporarily declined after the company reported a revenue miss, it topped analysts' bottom line expectations.

For the year Briggs & Stratton said that it expects to earn between $1.25 and $1.41 per share on revenue between $1.9 billion and $1.96 billion. 

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TheStreet Ratings has picked up on the company's rise and upgraded the stock's rating to "buy" from "hold" while also raising its letter grade to B from C+. TheStreet recognized multiple strengths in the company, including its impressive record of earnings per share growth, compelling growth in net income, good cash flow from operations, largely solid financial position with reasonable debt levels by most measures and notable return on equity. It feels that the company's strengths outweigh the fact that the company shows low profit margins.

BGG Chart BGG data by YCharts

TheStreet Ratings uses an algorithmic model to determine a rating for risk-adjusted total return prospect over 12 months.