The opportunity came about as both Shedden and McGuinness use Dunlop tyres and Honda race machinery, and both had been badgering their sponsors for a turn in the other's seat. Fortunately Honda and Dunlop were just as keen to find out, though there were a few nervous looks among the respective crews as Gordon and John swapped Nomex and leather for the day.
First up is John, driving Shedden's 350hp Honda Civic BTCC car. He avoids any stalls as he pulls away from the pit lane and is soon into a rhythm around the undulating Scottish track. It helps that he knows the layout from his early days of racing two-stroke 250cc bikes here and he soon settles into respectable 54-second laps. That's not too far off race pace for Shedden.
Once back in the pits, John gives his initial impressions. "The braking and cornering are unbelievable compared to the bike. You stick it in and it's just grip, grip, grip, so the apex speed is much higher. I'm braking about 100 metres later in the Civic than I do on the Fireblade."
Impressive, but Gordon's familiarity with his machine is telling. "I had to look at Gordon's data after the first run," laughs John. "Turns out he's braking 48 metres later than I was to begin with, so I could see where I had to sharpen up."
The bike fights back out of the corners though. "The power to weight ratio of the Fireblade means it just gobbles up the car on the straights," he says. "Also, the seating position in the car is alien to me as I'm strapped in. You can see so much more on a bike and aim for the apex, whereas in the BTCC car I had to judge it by experience instead of sight."
McGuinness is also surprised how much the car moves about in corners. "It skips around more than I expected and there's understeer. That's not something I'm used to as on a bike if the front lets go, nine time out of 10 times you're upside down. I've got massive respect for Gordon as it's hot, noisy and busy in there. You're working really hard and I was using muscles I didn't know I had. Mind you, I wouldn't mind having a BTCC Civic for track days..."
Now it's Gordon's turn and he seems more pensive than John was. Hardly surprising given the Fireblade has a power to weight ratio of around 900hp per tonne, compared to the Civic's 273hp per tonne. It doesn't stop him turning in quick times though and he's soon down to a consistent 55-second lap. Not that anyone was keeping tabs on such things, of course.
It's clear the physicality of riding a Superstock Fireblade at pace has surprised Gordon. His usual calm demeanour is accompanied by a sweat-soaked brow. "The bike is doing everything it can to rip your arms out of their sockets," he reflects. "Your brain has to work so fast to keep up and you're always conscious it's got to be you riding the bike rather than just hanging on. The acceleration is phenomenal. It's so rapid in parts of the track where the car isn't, but then I was also waiting and waiting to get on the power through corners where I can be hard on the throttle in the Civic."
As with John's drive in the BTCC car, it's the Fireblade's braking that surprises Gordon the most. "The brakes are so good and the tyres offer so much grip. In my mind, I was thinking there's only a contact patch the size of a credit card on the front tyre, yet it stops so well."
So, what are the big differences between car and bike? "You can push and find the limit in the BTCC car, perhaps go beyond it and just bring it back a little," says Shedden. "Even if you miss an apex, it's not a problem. On the bike, it's very difficult to get to that fine point of getting the most out of it but not overstepping the mark. Gauging where the limit lies is trickier, especially as I don't have the experience to slide the bike like John does and I don't want to end up on my ass.
"With the car, you're strapped in tight and everything is done through the fingertips. Also, you have exactly the same view every lap if you're doing it right. On the bike, you're up, down, side to side, so you see corners totally differently and your body moves a huge amount relative to the machine. Then there's the wind trying to push you off."
And similarities? McGuinness is characteristically matter of fact. "Both are a real laugh to go fast in or on. That's about it!"
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