Talking speedometer

I always remind Ace to drive slow. When we’re on the road, I am his talking speedometer because 60kph is already fast for me and I constantly tell him we’re driving fast.LOL. If he’s alone driving, I don’t know how fast he goes but I hope it’s not beyond 100kph because it’s too dangerous riding a motorbike at that speed. If there’s only a way for me to monitor his driving speed even if I am here at home, I would. But the only gadget that I could think of are radar detectors which he could detect if he’s been motitored by a radar. Hmm…it’s not for me. It’s for Ace so he could slow down before being issued a ticket for overspeeding.I hope there’s a gadget that I could use to monitor his speedometer reading when he’s on the road.