The European Bicycle Manufacturers Association (EBMA) lodged its complaint in September, saying that Chinese companies were flooding the EU market at prices sometimes below the cost of production.

The Commission, which oversees trade policy among the EU's 28 member states, said in a filing in the EU's official journal there was sufficient evidence to justify the start of an anti-dumping investigation. It would be concluded within 15 months.

The EBMA is also preparing a related complaint alleging illegal subsidies and asking for registration of Chinese e-bike imports, which could allow eventual duties to be backdated.

Such an investigation would be the latest in a string of probes into Chinese exports ranging from solar panels to steel and could raise trade tensions with Beijing, particularly with a subsidy inquiry into the support provided by the Chinese state.

China's commerce ministry said it would defend its companies' interests and urged the EU to respect World Trade Organization rules, telling the EU not to let its investigation lead to protectionism.

Bicycles have already been a flashpoint. The EU accused China last December for scuttling a global environmental trade deal by insisting that bicycles be included as a tariff-free green product. Chinese conventional bicycles have been subject to EU anti-dumping duties since 1993.

The EBMA said more than 430,000 Chinese e-bikes were sold in the EU in 2016, a 40 percent increase on the previous year, and forecasts the figure will rise to around 800,000 in 2017.

The group said European companies had pioneered the pedal-assist technology that e-bikes use and had invested about 1 billion euros ($1.2 billion) last year, but was risking losing its industry to China.