Ducati Corse general manager Gigi Dall'Igna says the team will see how the holds up during testing before deciding which bike riders Andrea Dovizioso and Andrea Iannone will use at the first race of the season on 29 March.
Dall'Igna told crash.net that there are still niggles with the new bike.
Dall'Igna said: "I don't want to take the decision regarding which bike we will use at the first race before the Qatar test. One track is not enough to verify completely the new bike and also I need more mileage on the engines.
"We still have to make another comparison between GP14.3 and GP15 at the Qatar test and after that maybe we can have a better opinion about which bike to use for the race.
"At the end this is the rider's choice. Not my choice. The rider has to do the best for performance and not follow my opinion. I did this [approach] all my life.
He added: "There are some small things that we didn't expect. But I think it is quite reasonable because the bike is completely new so you cannot think of everything before. You have to test, check what happens and try to solve the issues that you have.
"For me the [new] bike is a little bit faster than the other one in the chicane. There are some parts of the track where I think we gain quite a lot but there are some other areas where we have to improve a little bit to reach the GP14 performance.
"High speed corners I'm quite happy about the behaviour of the bike. I'm not really happy mainly in the braking zone and above all the final braking zone."