I have done something similar to that. We were in Austria and came upon a cable car going up an alp.
We decided to have a go. When we got to the top you had the option of going back in cable car or going on one of those gocart like things on a track. We decided if we didn't do it we would regret it so we had a go. We had a cart each. OH set off in front of me, I waited a while to let him get ahead then I set off. It was the scariest thing I have ever done. It wasn't in a straight line going down, oh no! It was going round and round the ruddy mountain. I had to use the brake most of the time. I lost my voice through screaming I want to get off. What made it worse there were three teenagers in carts behind me and they would come careering down at top speed then having to stop because they couldn't pass me. Then having to wait to build up a big enough gap to allow them to speed again.
When I eventually got to the bottom after what seemed an age I couldn't stop shaking. Then I discovered they had taken a photograph on the way down. I have never seen abject terror on anyone's face before but mine excels all terror stricken photographs.