The Bizarre Sell-Offs at Capstone Turbine Corporation, China Ming Yang Wind Power Group, and Revolut

Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis. 

While a slew of disappointing U.S. economic data sucked juice out of the broader market today, investors in three little stocks were left scratching their heads as the shares crashed for no apparent reason after rallying most days so far this year.

While shares of microturbine maker, Capstone Turbine shed 6% in early trading today, Revolution Lighting Technologies stock flickered out to give up 7% this morning. But China Ming Yang Wind Power Group turned out to be the real disaster today, with shares tumbling as much as 10% at one point in trading.

So was this just an unfortunate day for these stocks, or are their good days over?

Capstone looks safe
Despite today's fall, Capstone investors should be a happy lot because the stock still remains an outperformer -- until yesterday, the stock had zoomed a whopping 30% year to date. Capstone has already bagged several orders from markets across the globe this month, which seem to have convinced investors about the company's growth story. Important ones include orders from the lucrative and high-potential oil and gas sector, including those from leading companies operating in key regions such as Marcellus, Utica Shale, and Permian Basin.

With no adverse company news in sight, investors may have realized that all that good news may have already been baked into the price of Capstone's shares; therefore, they decided to take some profits off the table today. I don't think there's much to worry about here, since Capstone remains a compelling story, especially with global emission regulations getting stricter. With orders swelling, and top line growing at an accelerating pace, Capstone losses may soon turn around.

Nothing great about this revolution
Revolution Lighting's story, on the other hand, presents a completely different picture. The LED lighting solutions maker's last order is already more than a month old, and it has yet to open books this year. After gaining a staggering 400% in 2013, Revolution shares have cooled down, remaining flattish this month.

On a positive note, Revolution is spreading its wings to markets outside the U.S., while growing its base through acquisitions. Seesmart Technologies, which Revolution took over last year, is already adding great value to the company. But management is struggling to tame costs, and Revolution's losses are expanding. Moreover, LED lamps may have great prospects going forward, but it's a highly fragmented and competitive industry. With big names like Cree, Koninklijke Philips, and GE Lighting dominating the market, Revolution may have to create its own opportunities to get a foothold in the market.

Given the backdrop, last year's rally in Revolution's stock appears unwarranted. It seems to have turned into a trader's game, and today's fall only substantiates that. The shares took off yesterday, only to give up the gains today. Revolution is certainly not the brightest choice in the LED space for investors out there.

China Ming Yang just turned uglier
Unlike the other two stocks, China Ming Yang investors actually had a valid reason to dump the stock today. The just-released weak manufacturing data out of China could signal further economic slowdown, which naturally bodes ill for the company. Today's bad news wiped out most of the 12% year-to-date gains that China Ming Yang stock had clocked as of yesterday's close.

Like in Revolution Lighting's case, rising costs are eating into China Ming Yang's top line growth. Worse yet, management has no clue about when the company will expectedly break even. So investors practically have no way to assess where the company's headed to.

Bulls may be thriving on how China Ming Yang is rapidly gaining market share in the Chinese wind power market, but the company's global scene is nothing to write home about. Except for an order from India, it has little exposure to international markets. So if China slows down, China Ming Yang's growth could hit a wall. It looks dicey to me, and the shares could only get more volatile from here. Those with weak hearts should certainly stay away.