Ignite Ducati's Ben Spies will make a return to MotoGP action at Indianapolis later on today but still doesn't know how his injured shoulder will fare through the weekend and into the next three races in a row.

The Texan hasn't ridden since Mugello when he decided to knock it on the head but said then he would try and get some track time in, even on a road bike, before coming back. He hasn't managed this, so is in uncharted waters for first practice.

" I'm not worried, really, with anything other than just slowly getting back up to speed. Other than that, there's no worries. There's no perfect time to come back or anything like that. Sothis was the best time to come back with all the doctors and what was going on. So we just do what we can do and kind of start from scratch and build our way up," said Spies, speaking at Indianapolis.

"You can be the fittest person out there but what a bike does to you, you can't duplicate it in the gym. Even when you're 100 percent, when you give 100 percent the entire weekend, come Monday, every rider is sore on basically their whole body. These bikes are really physical. So there's no real way to test anything.

"I believe everything is going to be fine and we will slowly getting back up to speed. It's been, you know, about eight months, nine months since we've seen that speed. So just got to be patient and just work in a good way."