UPDATE: CarAdvice now understands that the i8 roadster is expected to be unveiled at the LA motor show in November, contrary to previous reports that indicated the plug-in hybrid drop-top would be revealed at September's Frankfurt motor show.
- shares

The upcoming 2018 BMW i8 roadster has been teased again by the Bavarian manufacturer on social media this week, ahead of a likely debut at the Frankfurt motor show next month.

A fleet of the plug-in hybrid drop-tops can be seen tearing up the roads in and around the European Alps, all wrapped in the eye-catching black and white camouflage that we have seen on previous prototypes (pictured).

BMW hasn't confirmed when it will reveal the i8 roadster, though it's been reported the final production version will make its debut at next month's Frankfurt motor show, ahead of a 2018 launch - the latter being confirmed by BMW's CEO last year.

The reveal of the convertible version should coincide with a rumoured mid-life update for the company's plug-in hybrid sports car, which should involve an uprated version of the i8's 1.5-litre turbocharged three-cylinder petrol engine - which is based on the unit used in several Mini models - along with a beefier electric motor and battery system.

Currently, the i8 pumps out a total of 266kW and 570Nm from its hybrid system, and recent reports suggest the refreshed model will push up to the 310kW mark. The current car's 7.1kWh battery is also set to get an upgrade to around 10kWh, which should improve the i8's "up to 37km" electric-only range.

If these rumours prove true, it would be logical to expect the i8's 4.4-second sprint from 0-100km/h to be improved as well.

The i8 roadster has already been previewed on two separate occasions, the first being the i8 Spyder concept in 2012 (above), along with the i Vision Future Interaction concepts in 2016.

Stay tuned to CarAdvice for more updates over the coming months.