I've never hugged a man so tight in my life. Perched high and riding pillion on the back of John McGuinness' Honda Fireblade, we're doing over 170mph down the Sulby Straight on the Isle of Man TT course. The wind is tearing the helmet off my head, the chinpiece obscuring my vision. All I'm aware of is a vague blur of passing shrubbery, a grey rush of dry-stone wall and - ahh, thank God, a 30mph sign...
Except this is a closed course with no speed limits, so just as I'm about to relax and breathe again, a whole village flashes past at warp speed, the bike doing well north of 100mph, the pistons sounding like they're trying to break free of the cylinders. Every single muscle and fibre is screaming to let go. My arms feel like dead weights. Try sticking your head out of the car window at 70mph to get an idea of a fraction of the wind resistance a TT biker's body has to endure. I don't mind admitting I let out a cry of anguish at this point.
It's not like John is even going that fast, for him. He's the most successful living TT rider, with 21 wins to his name and countless lap records. Such is his familiarity with the course, he knows where each individual drain cover is on a 37-mile lap. Yet despite his obvious mastery of these roads, it's still shocking to discover he's so relaxed on this run he has time to honk the horn at spectators as we go blasting past.
I'd gladly swap places with one of them right now. Halfway round the course and the only grip left between my two hands is the tips of my fingers. The thought of falling off suddenly becomes very real and very urgent. ‘If I'm holding on to nothing but the leather at the end of the fingers, will one of the gloves suddenly peel off and send me tumbling backwards?' Amid the maelstrom of speed and noise, I contemplate this with a surreal calmness at odds with the torture my body is being forced to endure.
John had said before we set off that if it was all getting a bit too much, I should give him a light punch to indicate he needed to slow down. I told myself there was no way that was going to happen, that I would not wimp out. But at the end of the Sulby Straight, when he's finally on the brakes, I offer a swift jab to John's stomach. Enough. Really. I can't take any more of this. Enough...
John brings us to a stop back at the race start. When I dismount, my right leg is shaking uncontrollably from cramp, my clothes are drenched in sweat, my neck aches and someone has to help me take my gloves off because I'm so weak.
After I've got over the initial shock, I turn to see John chatting and laughing with his mates. He looks like he's done nothing more than pop to the shops.
Would I do it again? Yes, but the truth is, at the time, I physically couldn't have managed it. A genuinely humbling experience.
Top Gear would like to send its condolences to the friends and family of Karl Harris and Bob Price, who tragically lost their lives on the TT course this week.