The ParkinGO BE1 Triumph team is set to undergo another change of driver line-up following the confirmation that Jason DiSalvo has chosen to leave.

The American, a race winner in AMA Supersport, Superstock and Formula Xtreme, was a last minute signing for the Italian-helmed concern following its decision to drop Garry McCoy and expand to four bikes.

However, DiSalvo has struggled to get on terms with the front runners - including team-mates Chaz Davies, David Salom and Matthieu Lagrive - to currently languish a lowly 15th in the standings at the half-way point in the season.

Indeed, DiSalvo comments that Triumph's decision to stretch resources to running four bikes has ultimately left him with a machine that isn't fast enough.

"The guys on the ParkinGO team really gave me an education about racing at this level, and I thank them for all they've done," DiSalvo, who has a best finish of eighth, said. "Being the only team with double the number of riders has made it difficult for each of us to perform at our best.

"I'm dedicated to the craft of racing that I love so much, but with my bike regularly showing 5-10 mph less speed than the others through the traps, there's a truth that neither of us can ignore.

"I hope that with one less rider these guys can do better and that I can find a team who's ready to benefit from my riding. Again, I thank the team for trying as hard as they could with what they have to work with."

The team originally announced pre-season that Davies and McCoy would form its line-up for the 2010 season, but later retracted that by launching a new four-rider line-up that included DiSalvo, Salom and Sebastien Charpentier.

Former champion Charpentier would quit after just one race, prompting the arrival of Lagrive.