Croft progress for Rizla Suzuki.

Rizla Suzuki riders Shane 'Shakey' Byrne and James Haydon each completed more than 100-laps during a test at the Croft circuit in North Yorkshire, on Tuesday.

The 2.12-mile flat, twisty and fast track is the team's chosen test circuit as its variety of corners and braking zones is ideal for proving developments to the race bikes.

Both Byrne and Haydon rode the latest versions of the GSX-R1000K6 fitted with a new fuel cell that is designed to optimize the weight distribution of the motorcycles. Initial reaction is the new bikes have improved stability at high speed and under braking.

The riders also worked through a series of chassis tests and Shakey, who took two podiums last tiem out at Oulton, tried a new set of forks. Dunlop was at the circuit with new tyres for the riders to try, with Byrne lapping close to record pace and Haydon only a fraction behind. The test was shared with the Vivaldi Suzuki team.

"It's been a very positive test for the team and there has been progress made on almost all fronts with the GSX-R1000," claimed team manager Roberts Wicks. "Thank you to Dunlop for supporting the test and to the riders for putting in such hard graft all day long. The whole team is enthused and encouraged by today's findings and will be using the information to make our bikes as competitive as possible for the next round at Mondello Park in less than two weeks time."

Round five of the 2006 Bennetts British Superbike Championship will take place at Mondello Park on May 21.