Castrol Honda's Jonathan Rea has successfully tested a new swingarm ahead of this weekend's Miller Motorsport Park World Superbike round and says it improves feel as grip drops off towards the end of a race.

The Ballyclare man also had some suspension parts to evaluate but mixed conditions at the Salt Lake City circuit meant the squad didn't get as much track time as they wanted.

"We nominated Miller as our test track this year because last season we really struggled with bike setup. I really enjoy riding here in America but the bumpy nature of the track makes it very difficult to find the optimum settings for the bike," said Rea.

"My team have pulled out all the stops though, and we had a lot of new items to test. The weather wasn’t on our side, so the track conditions were pretty dirty out there. I found a better feeling for corner entry with a new swing-arm and this really helped the feeling when the tyre life starts to drop. I also had some new suspension items to test and, while we found some positives, it will take more time to get it dialled in properly. We are in much better shape now to start the weekend and as always we will do our best."