Options trading investors appear to be riding high with Harley Davidson (NYSE: HOG) while viewing General Motors (NYSE: GM) as having little potential for an up move.

GM is virtually flat at $29.07 after falling as low as $28.85 earlier in the session. The stock has lost more than 25% since its January highs.

OptionMONSTER’s systems show that 5,039 GM July 30 Calls have traded against open interest of 2,881. Most of them were sold, with the biggest blocks of 2,950 and 1,600 going for $0.70, hitting the bid price at the time.

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We don’t see these calls traded against any stock today, so they could have been sold naked. Given how close the strike is to the current stock price, however, it is more likely that the calls were sold against existing long stock in a covered call position.

Meanwhile, Harley is revving higher after an upgrade today.

OptionMONSTER’s Heat Seeker tracking system detected the purchase of 5,000 HOG August 40 Calls, most of which priced for $1.28. Volume was more than triple the open interest in the strike.

HOG rose 4.40% to $37.45 in morning trading after UBS rated the motorcycle company a “short-term buy.” It’s been drifting lower for most of the year and took a hit on April 19 after the Japanese earthquake caused management to trim full-year guidance.

Nonetheless, HOG has been building support at the key $36 level where it peaked last year, which could make some investors think it’s in a bullish trend. There was also buying in the HOG June 40 Calls for $0.25 and $0.28, with more than 1,000 contracts changing hands.

Overall option volume in HOG is four times greater than average so far today, with calls outnumbering puts by 6 to 1.

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