What's better than momentum? Mo' momentum.

Let's take a closer look at five of this past week's biggest scorchers.


June 8 Weekly Gain My Watchlist
Westport Innovations (Nasdaq: WPRT) $30.55 31% Add
Yelp (NYSE: YELP) $19.64 25% Add
RF Micro Devices (Nasdaq: RFMD) $4.32 23% Add
Dangdang (NYSE: DANG) $5.50 21% Add
MAKO Surgical (Nasdaq: MAKO) $25.94 20% Add

Source: Barron's.

Westport Innovations took off after the maker of natural gas and liquefied petroleum gas engines and fuel systems inked a deal to develop natural gas powering solutions for Caterpillar's heavy machinery.

Yelp was the biggest gainer on the New York Stock Exchange. The fast-growing restaurant reviews website expanded into Finland last week. There was also a well-received boardroom addition, but the real driver here is simply that a busted IPO was redeemed during a welcome market rally last week.

RF Micro Devices received a pair of analyst upgrades. On Tuesday it was Avian talking up the value in the radio frequency component maker. The next day it was Davenport & Co.'s turn to wax bullish on the stock.

After tumbling 38.5% during the two prior months, Dangdang bounced back in a big way. Chinese stocks got a boost after the country lowered its key interest rates for the first time since 2008, and the popular Chinese e-tailer was a major beneficiary.

MAKO Surgical got a lift from an analyst upgrade. William Blair & Co raised its rating on the medical robotics specialist, noting that its forecast calls for strong sales in the second quarter.

More winners for you
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