Let me start with a word of caution... don't try this until you read the rest of my post. You might break something.
Out of curiosity only (no immediate need), I wanted to see if it was possible to push-start / bump-start / roll-start my Slingshot. So while rolling at low speed I started to let the clutch out, only to discover that the rear tire was starting to drag and the engine was not even hinting that it might start to turn over. And I don't think the rear tire was skidding just due to the low weight in the rear or poor friction with the road.
I've done push-starts before in other manual cars and this felt very different. It felt as if the engine was completely locked up. I tried this a couple more times, releasing the clutch even more gently, and I'm convinced the engine is not going to turn over. I think fully releasing the clutch at anything more than a crawl could lead to broken parts.
To answer the basics... ignition was in the On position, start button was glowing red, battery condition was good, gearbox was in 1st gear. If it makes any difference, this is a Canadian 2016.5 SL. And it starts just fine using the button.
Is there some kind of ignition interlock that prevents the engine from turning over? Is this a Canadian thing?