Honda introduced a revamped engine including a different firing order for the 2017 season, in a bid to erase the disadvantage its riders have faced in recent seasons.
Factory pair Marc Marquez and Dani Pedrosa have both won a race and LCR's Cal Crutchlow finished on the podium in Argentina, and the trio have reported gains, even if they do not feel they are a game changer.
Asked about the progress reported by Marquez, Pedrosa and Crutchlow, Miller said: “That's because their bike's better.
“It sucks. I feel like not only a second rider but a third rider, you know what I mean?
“I'm here, putting in the work and, it sucks to say but I had a s*** bike in the first year, last year wasn't much better and this year it seems I'm on the bike I got given at the Phillip Island test.
“Nothing has been updated; the same problem I've been complaining about since Qatar is still happening now.
“I'm still getting dicked on the acceleration, it sucks.”
Unsure whether anything would be forthcoming, Miller said his immediate focus was on getting further on top of the revised-construction front tyre introduced at Mugello earlier this month.
“Confidence feels good, I just got to keep working at it and like I said we're just getting the bike dialled in with this new front tyre,” he said.
“It will be interesting to see how this front tyre works (at Assen), it's not really a heavy-braking track and this tyre seems to suit more heavy-braking style.”