Casey Stoner believes it would be a 'great achievement' if he and Honda can take the 2012 MotoGP title fight to Jorge Lorenzo, given the issues stacking up against them.

The reigning world champion, who will retire at the end of this season, won twice in the opening three rounds but has now dropped 25 points from Lorenzo, who has won the last three events for Yamaha.

"We've had a tough last few races. We've given it everything we have, but didn't really get the results we wanted," said Stoner at Assen on Wednesday.

"There were a couple of opportunities to do better in the last few races, if I'd done things a bit differently, but in general we can't really complain. We've still been on the podium all but once, and getting good points.

"In general we are happy, but we need to pick up the pace a little bit and try and get a little bit more comfortable with the bike."

In terms of the bike, it is the ongoing technical issues which concern Stoner the most.

The RC213V has struggled to 'shake off' chatter problems ever since being paired with the original 2012 spec Bridgestone tyres - and the new softer front, which became the only option from Silverstone, has only made things worse.

"Chatter is the first and foremost issue," confirmed Stoner. "As we've improved the rear chatter and started to understand exactly what's causing it - it's still tricky to get rid of it - unfortunately with this new [front] tyre, we felt from the first moment we tested it that it made things a lot worse.

"The spec tyres that we were running last year, we didn't have any chatter. Then we put this year's [2012] spec tyres on, last year, and immediately got chatter. Then we put on the updated [2012 front] version and it just made it worse again.

"Every step Bridgestone has taken is making things a lot more complicated for us.

"But I suppose it makes the challenge bigger and if we can at least take the fight to the championship towards the end I think it would be a great achievement because everything seems to be stacking up against us at the moment."

Free practice for the Dutch TT at Assen starts on Thursday.