HOCKENHEIM, Germany - Just when it had got back on track, Lewis Hamilton's championship campaign spun off the road once again.The Briton pulled the gap to Nico Rosberg from 29 right back to four points by winnng at Silverstone and had a spring in his step right up until qualifying at Hockenheim.Then he speared into the barrier.'PAIN - BUT IT'S NORMAL'"I'm a little shaken, but I'm OK," he was quoted as saying by Germany's Auto Motor and Sport, having initially sounded winded on the radio as he reported brake failure. Team boss Toto Wolff said Hamilton banged his knees but was not injured."I have some pain, but that's normal - I hear it was 30G," said Hamilton, who said he is in no doubt whatsoever about racing on Sunday but from well down the grid.He insisted that Hockenheim qualifying was not the final straw in a title campaign that continues to derail as there are "a lot of races" still to go but he will be worried that the pendulum of momentum keeps swinging towards team mate Rosberg's.Fingers of blame are being pointed at a supplier of carbon brake discs. "Lewis decided at the last minute to use different discs," Wolff said. "Nico uses a different manufacturer."Team boss Paddy Lowe was even naming names: Hamilton's was using Brembo, Rosberg Carbon Industries. "I can't believe it really," said Hamilton. "The car felt really good, the setup was fantastic."GEARBOX WORRIESThe BBC reports that Hamilton's car might be switched over to Carbon Industries discs for the GP.Wolff said he hoped the gearbox was not damaged in the crash - changing it could send Hamilton back to 20th on the grid.Stay with Wheels24 for the 2014 German F1 GP weekend.Now THAT would be a race worth watching.