After a disastrous start to its debut 125cc grand prix season, Team Haojue has split from esteemed engine designer Jan Witteveen.

Haojue riders Michael Ranseder and Matt Hoyle have only started one race between them and the Chinese backed team withdrew from last weekend's Italian Grand Prix 'in order to concentrate on addressing the problems affecting the engine performance' of its machine.

The team had been battling to overcome a huge '17-22km/h' top speed deficit and, upon announcing the split with Witteveen, slammed the former Aprilia engineer for providing an engine 'neither race competitive nor reliable'.

Haojue even labelled the unique upside-down engine as 'potentially dangerous'.

"Team Haojue has terminated its contract with Dutch engine designer Jan Witteveen," said the statement.

"Jan Witteveen was contracted to deliver a state-of-the-art, race competitive 125cc GP engine and continue its development over a three year period. However, after 18 months of development it is clear from the engine's lack of performance in the early 2009 GP events, where the Haojue riders have either failed to qualify or sometimes crashed due to engine failure, that the engine is neither race competitive nor reliable.

"As well as the continued lack of performance and the reliability problems which make the machine potentially dangerous for the Team Haojue riders and other riders on the track at the same time, the Haojue team management has been deeply concerned by the lack of progress and communication from Witteveen on plans to overcome the problems."

Team Haojue is run by former Suzuki grand prix team manager Garry Taylor, with a chassis designed by Harris Performance. Motorsport legend John Surtees acts as team patron.

The team is owned and financed by Haojue, China's biggest motorcycle company with a production output of over three million machines in 2008.

It remains to be seen if Haojue will return to action at the Catalan Grand Prix on June 14.