Driving long curves

Experts:

What do we need to know about driving long curves?

It’s a question that’s long intrigued me, in view of the impact the long curve theoretically has on lap time.

There’s a sweeper on my local track that one spends maybe 3 seconds in at hire kart speeds. There’s no chance of jacking the inside rear off the deck, so that’s 3 seconds of massive drag on the lap time.

I’ve not tried it, but I’ve wondered whether there might be an advantage to driving the curve in 2 straight lines linked by a sharp turn through 90 degrees. Or several short straights linked my several turns of a few degrees.

Completely counterintuitive of course, but I suspect that most of us just reason that there’s nothing much we can do with long curves, and drive them as They’re shaped.

But if we deconstructed the driving of long curves, would we find an advantage hidden here?

Thanks for your thoughts.

Lee

I am certainly not an expert, but I have had some success in rental (hire) karts as well as 4-stroke racing karts.

My main question for you is what does the kart feel like? If you put just a little more steering in, will the back start to slide? Or does it just plow straight ahead no matter what you do? I certainly understand your concern about not being able to unload the inside rear tire and agree that it’s an important thing to be aware of. However, it may not be as big of an issue in some rental karts, at some tracks. Different tracks, or even just different karts at the same track can have wildly different handling. If the kart is somewhat balanced and the rear will start to slide if you turn the wheel more, then I would not be concerned with altering your line in a long sweeper.

Some thoughts about lifting the inside rear tire: to me, it is easier to notice with soft racing kart tires than it is with rock hard rental kart tires. However, with that said, a very tiny amount of steering input may bog down a rental kart significantly, while a normal amount of steering to get around a corner may unload the inside enough to reduce the drag. While this is unproven, I think in some rental karts, in some corners, it can help to be either at “full steering lock” (the max steering you normally get to in the corner) or perfectly straight ahead. No in between. Either unload the inside rear tire as much as possible, or set it down all the way and drive straight. I think you were already kind of thinking about it this way. The main place I think this thought process can help is long sweeping exits, where you can keep turning just a little longer, and then go completely straight to the next corner entry.

In some cases with rental karts I have found unconventional lines to be faster, but not in the way you’re talking about. With such a lack of power, sometimes it can be faster to really try to make the track as short as possible. Not only does this include simply running on the inside of the sweeper for the full length of the corner, but also not using the full width of the track on exit.

I do have an example, which is the closest thing to your suggestion of driving in two straight lines with a sharp turn in the middle. It was not a long sweeper though, but two corners that basically became a double apex corner. Outside of the track, there was a concrete runoff area. In rental karts, in the rain, on slick tires, you could drive into the corner very straight and go off onto the concrete area, suddenly have grip so you could turn, and then get back on the track and drive a relatively straight exit. I have never encountered such a situation in dry conditions in any kart.

So I guess what I am saying is, there is probably not a benefit to what you are suggesting.

I say give it a shot! See if it does anything to your lap time :man_shrugging:t4:

Report back!

Edit:

Google image overhead shot of the corner in question?

With the really long corners the fun is how early you can be on throttle?
And/; can you holfd it all the way out?

Usually with any kart but the most powerful, you need to be on the throttle very early in the turn. If you feel one of the rear tires is “dragging” or binding the kart, try leaning outwards while going around the corner. It may lighten the load on the inside rear enough to free the kart up. If you look at pictures of some of the top European guys in the wet, they’ll be leaned out over the outside side pod.

1 Like

That’s basically what I do on longer turns, esp if it’s a flat out turn. Lean out to unload the inside rear as much as you can. I can’t say what difference it makes… But it looks cool :smiley:

image

Some great advice here - especially James your bit about looking cool. :sunglasses:

You’ll find the sweeper in question top left of photo. there’s no driving needed to get through on full noise (85kph - the KZ2s hit this at 170 apparently) - but I’m looking for something to ‘do’ on this piece of track - such as keeping as much load off it as I can.

Benn, you’ve answered that I think - just lean out. Simple as that is, I hadn’t thought of it so I’ll give it a go at the season opener in a couple of weeks and let you know what I come up with.

Johnathan: I subscribe to that ‘all or nothing’ Steering approach too - hence this question. I’ve been tracing the inside of the curve all the way through on the shortest line I can find, with the inside rear on the kerb / grass to minimise the force it feels. Interestingly, a guy in my crew observed one of the fast guys turning in from the concrete apron in our last wet enduro, exactly as you describe. So looks like the word on that is out…

Thanks for your comments.

@Motormouse
Lee,
I’m doing a bit of rentals these days and your question intrigues me.

What did you discover vis-a-vis straightening out the turn? Did you take it to the track?

Hiya Dom.

Since asking that question I’ve become an aggressive proponent of ‘unloading’. I now drive with my attention on the inside rear with a view to getting as much pressure off it as I can. Which means me helping the g-loading grind me into the outer side of the seat.

As always, I don’t know whether its right. But I do know that I’m walking away with trophies that I wasn’t before.

Excellent. Go get em. I gather turning that corner into two straights was a bust?

It’s the right question, and I assume the answer is ‘yes - a bust’. I haven’t figured out a portable timing solution with which to measure splits, so I can’t conclusively say. I feel that unloading the inside throughout the turn is better than doing nothing, but better than driving a hard ‘V’? Jury’s out.

The hard V is an interesting idea in a kart with no grunt. Given the hugeness of that turn, I can see why you’d consider it.
You’d think, given the engine, you’d loose too much rpm forcing a V rotation.

For the life of me I can’t figure out how you can do that.

I think he means leaning towards the outside of the corner.

“The lean” trying to think of a video that gives a good example. Any ideas?

Its in the wet but look for Schumachers gentle lean versus those around him doing a violent lean.

Thanks for the share Nik.

This video has been locked down. I assume from your description that most of these guys are doing what I do - getting off the inside rear as hard as possible - while the great Schumacher is doing a much gentler version of this?

If so, that’s telling because of how aggressive he usually was at the wheel. I’m guessing he’s reasoned that the water lubricates the bind between the 2 rear tyres, and is using some weight on the inside rear chasing grip?

I’ve tried with a different link.

I think he’s aiming for a sustained inside rear wheel lift rather then a pop it up down situation. He’s actually the only one of the front group who’s doing the leany thing. I’ve personally never done it and consider myself pretty handy in the wet.

Nik: awesome share thanks.

You’re right - he’s the only one doing gymnastics at the wheel. But he’s also the only one who’s gone 16th to 2nd! In a field of the worlds best at that. Granted, he probably knows the track better than anyone, but that result looks pretty conclusive in favour of the lean to me. What do you think?

I thought I saw him leaning aggressively forward coming off the turn a couple of times too. Whats he up to?

I spoke to someone who knew him when he raced karts and he (and Liuzzi where the only two this person told me about, also in the video, no.7) had a very refined way of placing their body weight around the kart depending on the corner they were negotiating. So even in the dry they were leaning very specifically depending on the grip needs.

He definitely seems to lean forward, I’m not sure I spot the aggressive part, but he seems to be pulling his bodyweight towards the steering wheel at a number of points.

I was sure he finished on the podium in this race (but it shows him spinning) so I wonder if this is Final 1 or the day before the podium. There was a lot of, erm, iffyness about this race lol. It’s Schumi’s track (his dad owned it and he grew up there), he allowed Tonykart (with him) to test there in the weeks running up to the event but didn’t allow any of the other teams. This isn’t to say he isn’t a great driver, but he gave himself every advantage, which is part of his greatness for sure.