A coroner has called on Transport for London to urgently review its cycle superhighways to identify areas of reduced grip, stating "there is a risk of future deaths" unless action is taken.The comments were made in a "report to prevent future deaths" relating to an ongoing investigation into the death of a motorcyclist called Milan Dokic who crashed while riding on a wet cycle superhighway in Battersea in March 2016.Fiona Wilcox said her concerns were "too urgent to wait until the full hearing of the evidence to be addressed"."In my opinion there is a risk that future deaths will occur unless action is taken," she sates in her report, adding she was aware that cyclists had expressed concerns about the surfacing.The report goes on to state, "The use of road surface with reduced grip on the CSH [cycle superhighway] compared to the usual road surface represents a hazard to road users making it more likely they will lose control of their vehicles."Ms Wilcox suggested it was unknown how much of the cycle superhighway had a low grip, although the concern appears to relate to the blue painted sections, and stated "it may be widespread and as such other dangerous areas may exist"."TfL should therefore undertake an urgent review of all such road surfaces and replace it with a higher grip surface," she adds."CSH should have increased rather than reduced grip as cyclists are vulnerable road users."Reporting on the incident, Ms Wilcox relates that when the area that the motorcyclist came off was tested by the collision investigator the blue lane of the cycle superhighway was found to offer "a much lower grip than the conventional road surface".It had "a skid resistance value of 56.3 compared to the road surface of 77.05 and the CSH before the pedestrian crossing [which had] and even higher skid resistance value of 89.85".No conclusions have yet been reached as the inquest has not been heard.Leon Daniels, TfL’s managing director of surface transport, said, "Our thoughts are with the family and friends of Milan Dokic. We’re preparing our response to the coroner and carefully considering the issues raised. We are confident our cycle superhighway network is improving the safety of London’s roads."We are working hard to tackle the dangers on London's streets. We are investing in safer cycle lanes and junctions, working with boroughs to introduce more 20mph limits, removing the most dangerous heavy goods vehicles from the capital and continuing our road safety education and enforcement programmes."The inquest is due to be resumed and concluded in the summer. Newer cycle superhighways, such as CS3 (East-West) and CS6 (North-South) are substantially segregated and have no, or next-to-no, blue surface, TfL added.