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Discussion Starter #1
Okay, so you are riding a GSXR1000 when the road is a bit slippy, maybe wet, dirty, perhaps even has some ice.

Convential advice would be to ride in a higher gear, but I started thinking about this.

Assume you are being as gentle as you can on the throttle. If you are in a higher gear then isn't a small movement on the throttle, assuming you have the torque, going to speed the bike up by more than the same movement in a lower gear?

So lets say you are riding at 30mph, should you ride in 1st, 2nd, 3rd or 4th when slippy?
 

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I would rather be at 3,000 rpm than 6,000 rpm on a wet road.
I also try to remember to put the bike in B mode when it's wet because it seems like it has slower throttle response.
 

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Captain Obvious ... because obviously it’s obvious
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A higher gear is a less favorable torque ratio, which is compounded by the fact that you make less torque at a lower RPM. If I'm in the wet at 30mph, I'm probably going to in 4th or 5th gear and lugging the engine. And I'll never be in the ice, because god help your soul.
 

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You have an L4? Use C-Mode ;)
 

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Discussion Starter #7

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It's the only time I have used the S-DMS, especially in drizzle when the oil is lifted off the road, on my 750 it mades a huge difference.
 

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Rectum Rupticus
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Okay, so you are riding a GSXR1000 when the road is a bit slippy, maybe wet, dirty, perhaps even has some ice.

Convential advice would be to ride in a higher gear, but I started thinking about this.

Assume you are being as gentle as you can on the throttle. If you are in a higher gear then isn't a small movement on the throttle, assuming you have the torque, going to speed the bike up by more than the same movement in a lower gear?

So lets say you are riding at 30mph, should you ride in 1st, 2nd, 3rd or 4th when slippy?
 

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Discussion Starter #10
It's the only time I have used the S-DMS, especially in drizzle when the oil is lifted off the road, on my 750 it mades a huge difference.
Okay, I tried C mode this morning and in traffic I honestly wouldn't have known if I hadn't checked the dashboard to see it was selected. I could tell once you started to accelerate more above 30mph but sadly that's not much of my normal commute!
 

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Ex-Lady Supermod
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Okay, I tried C mode this morning and in traffic I honestly wouldn't have known if I hadn't checked the dashboard to see it was selected. I could tell once you started to accelerate more above 30mph but sadly that's not much of my normal commute!
Don't know what to tell you as on my 750 A/B/C are noticeable.

 

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Here's an argument for riding at lower gears/higher engine speeds on the wet: while going at a higher engine speed, will require more throttle control to avoid actively sliding the rear, suppose the rear does lose traction, say because you cross a spot where the water film is deeper, or where there's more contamination on the road, because you're near a traffic light. As the tire starts spinning on a wet road, the available traction drops dramatically as the spin develops [1] and the engine soon operates more or less unloaded, or, at least, with a much lighter load. The problem with being at a higher gear in such a scenario, is that that you'll likely be at a larger throttle opening, than if you had been a couple of gears down. Once the engine starts becoming unloaded, it's going to raise its speed, much like as if you'd slipped the clutch, only in this case the wheel is going to spin faster along with it, losing more traction, unloading the engine even more, etc.

This will generally happen whether you're at a higher or a lower gear and I think it also explains why rear wheel spins tend to be more violent in the wet. The difference is that, at a higher gear, the engine will accelerate faster and further [2], making the spin more sudden and violent. Couple this with the fact, that it won't happen in response to rider input, hence without warning, likely to catch you off-guard and you can have a dangerous situation, especially on higher-powered bikes.

[1] Although I'm not sure about this, I think that's because as the wheel starts spinning, the relative speed of the tire-pavement contact patch rises, much as if you were going much faster, so that the same situations that govern aquaplaning arise.
[2] To simulate this, to some degree, try going at a certain constant speed, the one you typically ride when the road is wet, and pulling the clutch in. See how fast and far the engine speed rises, then repeat the experiment three gears higher.
 

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If it's raining out, which it often is in Florida, I am short shifting around town. There is no need to apply any additional torque to the ground, especially on a 1000. For me, it's no more than ONE gear higher for 99% of wet weather scenarios.
 

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I should have mentioned: I don't mean to imply one should ride always in the powerband or in first gear if not possible. Obviously, a compromise must be made, between having an overly touchy throttle and a potential for a sudden and violent slide-out of the rear wheel. Riding one gear higher (instead of 3, say something like in 5th and at 3000rpm), sounds like a reasonable choice in that context.
 

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Captain Obvious ... because obviously it’s obvious
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Here's an argument for riding at lower gears/higher engine speeds on the wet: while going at a higher engine speed, will require more throttle control to avoid actively sliding the rear, suppose the rear does lose traction, say because you cross a spot where the water film is deeper, or where there's more contamination on the road, because you're near a traffic light. As the tire starts spinning on a wet road, the available traction drops dramatically as the spin develops [1] and the engine soon operates more or less unloaded, or, at least, with a much lighter load. The problem with being at a higher gear in such a scenario, is that that you'll likely be at a larger throttle opening, than if you had been a couple of gears down. Once the engine starts becoming unloaded, it's going to raise its speed, much like as if you'd slipped the clutch, only in this case the wheel is going to spin faster along with it, losing more traction, unloading the engine even more, etc.

This will generally happen whether you're at a higher or a lower gear and I think it also explains why rear wheel spins tend to be more violent in the wet. The difference is that, at a higher gear, the engine will accelerate faster and further [2], making the spin more sudden and violent. Couple this with the fact, that it won't happen in response to rider input, hence without warning, likely to catch you off-guard and you can have a dangerous situation, especially on higher-powered bikes.

[1] Although I'm not sure about this, I think that's because as the wheel starts spinning, the relative speed of the tire-pavement contact patch rises, much as if you were going much faster, so that the same situations that govern aquaplaning arise.
[2] To simulate this, to some degree, try going at a certain constant speed, the one you typically ride when the road is wet, and pulling the clutch in. See how fast and far the engine speed rises, then repeat the experiment three gears higher.

Your throttle opening at a higher gear is usually not going to be greater than a lower gear unless you are severely lugging the engine, which would be because you're trying to allow more air in, but it's not having much of an effect. If I'm running in first/second gear at 70mph, the throttle position is significantly advanced compared to being in 4th or 5th.

The thing I'd be more worried about is that if your tire does spin, the gearing ratio in a higher gear will cause the wheel to spin faster.
 

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Your throttle opening at a higher gear is usually not going to be greater than a lower gear unless you are severely lugging the engine, which would be because you're trying to allow more air in, but it's not having much of an effect. If I'm running in first/second gear at 70mph, the throttle position is significantly advanced compared to being in 4th or 5th.
I'm not sure how you mean that, but I'm assuming going at the same constant speed in both cases, to make them comparable. Going at a certain speed will require virtually the same power in any gear gears and, since at a higher gear your engine speed is going to be lower, you're going to need more throttle to produce that power. If you mean that the throttle opening won't be substantially higher, then depending on the gearing difference, that may be the case, but, since we're explicitly discussing shifting to higher gears to reduce the engine output and make the throttle response less sensitive, I'm assuming it will be substantial, by definition.

The thing I'd be more worried about is that if your tire does spin, the gearing ratio in a higher gear will cause the wheel to spin faster.
That is also a valid point, that I have missed entirely. Thanks for pointing that out.
 
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