Jorge Lorenzo feels team-mate Marc Marquez's imperious MotoGP form means Honda is reluctant to make changes to its RC213V that may help out other riders.
The three-time MotoGP champion replaced a struggling Dani Pedrosa at the Honda works team at the off-season, but has so far struggled to attain results.
Marquez, who has given Honda five riders' titles in six years, has taken three wins from five races to lead the 2019 standings, while Lorenzo holds 14th place.
Marquez claimed pole position at Mugello on Saturday, with Lorenzo, who qualified 17th, saying his team-mate "rode incredibly" en route to an "unbelievable lap time" but insisted other Honda riders are finding it tough.
"Obviously I'm thinking about me, I'm not particularly interested to help the other riders - and the other riders, if you ask them, they will tell you that they follow their way," Lorenzo said.
"But I believe, as I did it with other brands, that I'm a very sensitive rider, with a lot of experience.
"If I can improve my feeling on this bike and make it more easy [to ride] it also will benefit the speed and the comfortability of other riders.
"And even for Marc - if we can make a smoother bike under acceleration then we can have a bike that stops better in the entry of the corner, and Marc can also go faster.
"Obviously he's winning, five from six [titles], so they [Honda] don't let you change so much, no? They keep winning with Marc.
"But I think the goal with Honda is to try to, in a very competitive category, at least to try to make first and second [places]. And this is the goal: to try to make a bike that is competitive with other riders."
Lorenzo also endured a difficult start under his previous employer Ducati, but changes to the bike transformed him into a frontrunner during his second season, and with a crucial new fairing already in the pipeline, he is hopeful of a similar turnaround at Honda.
Asked if he was trying to make the Honda bike more akin to his Desmosedici from last year, Lorenzo said: "No, Honda will be Honda, Ducati will be Ducati.
"The Ducati I tried the first time that I jumped on on the first day had nothing to do with the Ducati I finished [with]. I think Honda can make a similar process in the future.
"We are limited about many things in the rules. We don't have so much time, this I understand. One track will be better, one track will be a little bit worse. Maybe the next track [Barcelona] will be a little bit better than this one.
"We need to be patient enough, keep working, keep motivated, keep positive. With more kilometres I believe I will be better on the bike, but the real difference will be made when I have these pieces that I am demanding.
"But obviously it's a process of both - evolution of the bike and the understanding to ride the bike better. When we put this together, we'll make a big step."