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Closed Throttle Steering?
- Thread starter justride
- Start date
I got introduced to this at Racing School Europe a few weeks ago (by Troy Corser). He wanted us to do all our downshifting at points that I would consider to be crazy early, turn in early, square off the corner and double-apex it in the interest of starting to accelerate earlier, even if it meant lower cornering speed. I understand the point but it isn't something I've ever tried (in 30 years of doing this - but not on modern superbikes ...)
Here's a big factor ... modern superbikes have drive-by-wire throttles with quickshift up and down, and automatic rev-matching on downshifts, which on the bikes we were riding (2020-2021 BMW S1000RR) were absolutely bumpless, even when shifting down to 1st ... something that I never otherwise do. Another big factor on modern superbikes ... traction control that makes 1st gear manageable.
I haven't ridden my own race bike since taking that school ... and I'm not convinced how applicable it's going to be. My own bike doesn't have drive-by-wire, and therefore doesn't do automatic rev-match downshifts, I have to rev-match myself - which I can do ... but at Grand Bend, once started, I'm never below 3rd gear. It's not even possible to use 2nd at race pace. I may try keeping an eye on the revs to see where there's an opportunity to be a gear lower. There's a few things I'm going to try, if I still remember it 6 months from now.
The other thing is that the early-apex, square it off, accelerate out while double-apexing the corner works if you have something with prodigious acceleration (superbike) ... maybe not so much on the smaller bikes where nothing much happens when you twist the throttle. If I lose cornering speed, I'm dead in the water exiting the corner.
I'm 20 seconds a lap off World Superbike lap times, so what do I know. (30 kg too heavy, 20 years too olde)
Here's a big factor ... modern superbikes have drive-by-wire throttles with quickshift up and down, and automatic rev-matching on downshifts, which on the bikes we were riding (2020-2021 BMW S1000RR) were absolutely bumpless, even when shifting down to 1st ... something that I never otherwise do. Another big factor on modern superbikes ... traction control that makes 1st gear manageable.
I haven't ridden my own race bike since taking that school ... and I'm not convinced how applicable it's going to be. My own bike doesn't have drive-by-wire, and therefore doesn't do automatic rev-match downshifts, I have to rev-match myself - which I can do ... but at Grand Bend, once started, I'm never below 3rd gear. It's not even possible to use 2nd at race pace. I may try keeping an eye on the revs to see where there's an opportunity to be a gear lower. There's a few things I'm going to try, if I still remember it 6 months from now.
The other thing is that the early-apex, square it off, accelerate out while double-apexing the corner works if you have something with prodigious acceleration (superbike) ... maybe not so much on the smaller bikes where nothing much happens when you twist the throttle. If I lose cornering speed, I'm dead in the water exiting the corner.
I'm 20 seconds a lap off World Superbike lap times, so what do I know. (30 kg too heavy, 20 years too olde)
I like the way Neeves explains it in the 2nd video. It's helped me improve at the track this year, so I can give my perspective as a casual track day rider in novice to intermediate groups this year (no racing).
Thinking to Turn 2 at Shannonville Long Track this year as an example and on an SV650. Initially, I was having trouble getting it right. Sometimes braking too early, hitting the apex too early and drifting wide as I accelerated out, again, too early - limiting throttle on exit to avoid drifting out too far. Then sometimes braking too late, missing the apex altogether, slowing right down to get the bike to turn in and accelerating out when pointed in the right direction.
Thinking back, I think I was too eager to either be on the brakes or on the throttle, and came to learn that it's ok to be off the brakes and off the throttle for a period of time.
So I have my braking marker, on the brakes firm at that point, trail off with more lean, off throttle for a short period of time, then gradually increase throttle as I pick the bike up on exit.
With this, I've found that (1) I can fine tune corner entry by adjusting time trail braking / time off throttle, so I am able to hit the apex more consistently, (2) dynamically, it works - being off throttle and with engine braking the weight is still mainly on the front, so the bike wants to turn in - then when the exit opens up, on the throttle, load the rear as you pick the bike up - in contrast, when I was getting on the throttle too early, even before the apex, I was loading the rear too early, then limiting throttle to avoid running out wide and overall just not working with the bike.
Maybe it's second nature / something that goes without saying for more advanced riders, but for me it's been very helpful.
Thinking to Turn 2 at Shannonville Long Track this year as an example and on an SV650. Initially, I was having trouble getting it right. Sometimes braking too early, hitting the apex too early and drifting wide as I accelerated out, again, too early - limiting throttle on exit to avoid drifting out too far. Then sometimes braking too late, missing the apex altogether, slowing right down to get the bike to turn in and accelerating out when pointed in the right direction.
Thinking back, I think I was too eager to either be on the brakes or on the throttle, and came to learn that it's ok to be off the brakes and off the throttle for a period of time.
So I have my braking marker, on the brakes firm at that point, trail off with more lean, off throttle for a short period of time, then gradually increase throttle as I pick the bike up on exit.
With this, I've found that (1) I can fine tune corner entry by adjusting time trail braking / time off throttle, so I am able to hit the apex more consistently, (2) dynamically, it works - being off throttle and with engine braking the weight is still mainly on the front, so the bike wants to turn in - then when the exit opens up, on the throttle, load the rear as you pick the bike up - in contrast, when I was getting on the throttle too early, even before the apex, I was loading the rear too early, then limiting throttle to avoid running out wide and overall just not working with the bike.
Maybe it's second nature / something that goes without saying for more advanced riders, but for me it's been very helpful.
I like Neevesy's explanation better too, because it clearly describes what the technique is trying to solve: low entry speed after the turn-in, with the associated behaviour of getting back on the throttle before the apex to compensate. The closed throttle is just the gauge of whether you could have carried more speed into the corner or not.
For me, a slow entry speed was really a symptom of low trust of the front tire. It feels safer to gradually tip the bike in until you get to full lean, and then make up the lost time by getting back on the throttle earlier. The thing that helped me the most to improve in this area was an exercise at Toni Sharpless' school on a minibike. The drill was to just hammer the front brake as hard as I could while turning in, until the front wheel started to slip. Overall speed wasn't important; the only point of the exercise was to work the front tire as hard as possible by simultaneously braking and turning. In 5 minutes I had a much better understanding of how much front-end traction was available, and I was instantly more confident on turn entry when back out on track. That drill was so valuable, I could do another whole day of just that.
However, that's a drill that you do on a minibike at jogging speed, not something that you do on a full sized bike on an open track. Neevesy's advice to just gradually release the brakes earlier and earlier in a corner is a safer way to carry more speed to the apex and build trust in the front tire. The 'closed throttle' technique is just to prevent you from cheating by slowing down too much and then hiding it with the gas.
For me, a slow entry speed was really a symptom of low trust of the front tire. It feels safer to gradually tip the bike in until you get to full lean, and then make up the lost time by getting back on the throttle earlier. The thing that helped me the most to improve in this area was an exercise at Toni Sharpless' school on a minibike. The drill was to just hammer the front brake as hard as I could while turning in, until the front wheel started to slip. Overall speed wasn't important; the only point of the exercise was to work the front tire as hard as possible by simultaneously braking and turning. In 5 minutes I had a much better understanding of how much front-end traction was available, and I was instantly more confident on turn entry when back out on track. That drill was so valuable, I could do another whole day of just that.
However, that's a drill that you do on a minibike at jogging speed, not something that you do on a full sized bike on an open track. Neevesy's advice to just gradually release the brakes earlier and earlier in a corner is a safer way to carry more speed to the apex and build trust in the front tire. The 'closed throttle' technique is just to prevent you from cheating by slowing down too much and then hiding it with the gas.
Shut throttle while heavily geared down 
also puts braking load on the rear tire while not braking the front, encouraging a controllable rear slide rather than a front lowside. The chain pull also encourages the rear suspension to not top out. There's a lot going on!
also puts braking load on the rear tire while not braking the front, encouraging a controllable rear slide rather than a front lowside. The chain pull also encourages the rear suspension to not top out. There's a lot going on!|
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