Yamaha and Honda have said plans for a £12.5m budget cap on what factories can spend on their 1000cc MotoGP projects each season is impossible to police.
Dorna is keen to implement a budget restriction of 15m Euros to entice new factories like BMW into MotoGP by making it much more financially viable to enter.
But while Yamaha and Honda agree a maximum spending limit is a good proposal, both share the view it is impossible to ensure nobody spends more than agree cap.
Yamaha boss Lin Jarvis told MCN: “To police a budget cap in my opinion is virtually impossible. To even start thinking about policing it is a bad idea because you will consume an awful amount of time.
"We will only give money to the accountants and the FIM will probably have to increase their staff by X amount to carry that out. I don’t think it is the right way to go but the idea is good.
"The idea is to limit the expense of a manufacturer to reasonable parameters so we can encourage more manufacturers to come back and not need an endless budget.
"But whether 15m is the right number, I have no idea. That’s a number that’s been thrown out but I don’t think there has been any real serious calculation.”
And HRC boss Shuhei Nakamoto told MCN: “It’s impossible to police this. How can you check how much they are spending in R and D? We fully agree with the philosophy but 15m Euro is too difficult for us.
"I think more realistic is something closer to 20m. I think that is reasonable for a company to join MotoGP. I have heard some rumours that BMW is already spending 15m Euro in World Superbike.
"If they come to MotoGP they could find bigger sponsorship to cover the extra costs and get more exposure for their brand.”