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How much force is required to steer at speed?


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At my camp last week, @Cobie Fair demonstrated how much force he applies to the bars to quicksteer into T1; a direct visceral demonstration. Compared to my perception of my own bar inputs it's at the other end of the spectrum. I'm wondering if bar pressure can be measured or calculated as a function of speed and desired lean rotation speed.

There are some corners where it seems to make sense to quicksteer and I can do it without overthinking and there are others where my SRs discourage me from pushing harder. I'd like to overcome this barrier.

I thought that if I could duplicate the amount of force required in a quantifiable way, I could "sneak up" on the right amount, bypassing my SRs.  

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What sorts of corners trigger your SRs? What do you think (or what do your SRs think) will happen if you push on the bar harder?

There are way too many contributing factors involved to try to calculate how hard you'd have to push at a given speed. Handlebar length and angle (giving you more or less leverage) is an obvious one that can dramatically change the force the rider needs to impart, and its an item that varies a lot by motorcycle type and model. Steering angle of the bike, type of tires, etc. would all contribute too. Far simpler just to experiment with it for yourself on your own bike.

For corners where you feel a bit uncomfortable steering the bike quicker, here are some things to observe when you ride, that could impact your confidence steering the bike quickly:

1) Do you have a specific apex chosen that you want to hit?

2) When do you look in to that apex, do you give yourself enough time to see it, to be able to make a positive and effective steering input?

3) When do you move your body, are you solidly in position before you have to make your steering input?

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Yes, there are lots of variables (I didn't consider that) but I am still thinking there's GOT to be a way to measure or calculate this empirically, at least for a specific bike/setup. Ideally, we only need to know how much force is required at the contact patch using model rubber and model asphalt, since that has a known coefficient of friction. The other factor would be overcoming the gyroscopic forces.

It's probably easier to say what corners I feel comfortable with quicksteer than the other way around- LoL. I can easily do it in a series of esses, full lean to full lean. Oddly enough, I have a hard time when I can see both entry RP and apex RP. This doesn't vary much when sitting in the middle of the seat or hanging off, though hanging off does distract me enough that I don't need to think about the mechanics of steering and can quicken a little, but not by enough to raise my entry speed consistently.

I did find by reviewing my Video Bike footage, that I tended to enter/exit corners in relatively the same speed bands, regardless of radius.

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I forgot to talk about my SRs. My best guess is that my concern is about having the front end wipe out. I've had it happen once. Tires weren't cold and there was no discernible debris or fluids on the road. I had a rider following me on the street and when I went to turn left, the bike just ended up on the pavement with no explanation. Neither of us had a clue what happened.

I don't think I have a good perception of front end traction, but I can feel front end slips and slides on bad pavement. I do think I've recently opened the door to being able to feel rear grip with the throttle and it gave me more confidence to be able to play with the amount of throttle on corner exits to now be able to discern bands of power applied (on the gas but decelerating, on gas holding steady, on gas slight acceleration, on gas driving, on gas full boogie).

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1 hour ago, Jaybird180 said:

 Oddly enough, I have a hard time when I can see both entry RP and apex RP.

That is a good observation.

Do you give the turn point less attention in those situations? How much attention do you allocate to each point, or do you just view them together? If you allocate more attention to one point than the other, does that change during the corner? If so, when and what is the shift?

If you increase your entry speed, do you still keep the same turn point or do you turn in earlier?

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I'll have to go back and test to see if I have a good, working 2-step. Closer towards the end of day 2, I could get closer and more consistently to the turn point before cheating the turn. However, I do place more attention on apex accuracy.

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58 minutes ago, Jaybird180 said:

I'll have to go back and test to see if I have a good, working 2-step. Closer towards the end of day 2, I could get closer and more consistently to the turn point before cheating the turn. However, I do place more attention on apex accuracy.

If a rider had a correct apex chosen but turned in a little too early, what would the rider have to change about the steering to still hit that chosen apex?

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1 hour ago, Jaybird180 said:

Slower steering and would also have to delay throttle roll-on.

Exactly, so turning in early makes it difficult, and counter productive, to quick turn the bike  


Your plan to investigate your two step sounds like a good starting point for improving your quick turn in those turns where you can see both TP and apex at the same time. If you can eliminate turning in early, you may find it much easier to improve your steering rate, which could then allow improvements in entry speed. 

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