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Old 03-24-2008, 11:17 AM   #1
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Default Practical Application of Theory

Much space in many motorcycle journals and books on the effects of accleration and deceleration; many magazines tout the wonderful benefits slipper clutches.....but why are they desireable?

When you accelerate a motorcyle, a couple of things happen: the weight transfer of acceleration slightly compresses the rear suspension, simultaniously unloading and extending the front forks. At the same time, the front sprocket is tightening the top run on the chain pulling the suspension upward and accentuating the squat of the rear end. This squat loads the rear tire, enhancing rear wheel traction, but also the extending forks, extends both rake and trail, widening the turning radius and slowing steering inputs.

Conversly, slamming the throttle shut mid-turn in response to coming in too hot or making panicky mid-course corrections has just the opposite effects...... sudden unloading of the rear (and the decrease of traction that goes with lack of load), shortening of rake and trail (and the sudden quickening of steering that accompanies it) adding load to the front tire.

That's why the old racers saying of "go in slow, come out fast" applies to the streetrider, too. Negative or neutral throttle in turns leaves the rider in a decreased traction mode, encouraging both rear wheel slides and front wheel washouts.

Get your braking done early, and use a little positive throttle ALONG WITH A LITTLE BIT OF REAR BRAKE to encourage squat and the additional rear traction that goes with it.

Happy Riding
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Old 03-24-2008, 11:23 AM   #2
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Have you ever considered writing for a Motorcycle Magazine? Everything you post has tons of depth, you have ridden a ton of different motorcycles, you are an all around knowledgable person.
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Old 03-24-2008, 11:25 AM   #3
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Excellent tip. I always enter my corners this way since I read the book, Sportriding Techniques.
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Old 03-24-2008, 05:21 PM   #4
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i had a perfect example of this, went into a on ramp too hot and had to remember what i have been taught and not my natural instinct to cut the throttle, poured a lil throttle leaned it over, put trust in my tires and made it though, def didnt have chicken strips after that ride, but the last time i enter a ramp at >80 with out leathers on
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Old 03-24-2008, 05:42 PM   #5
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Originally Posted by drewpy View Post
i had a perfect example of this, went into a on ramp too hot and had to remember what i have been taught and not my natural instinct to cut the throttle, poured a lil throttle leaned it over, put trust in my tires and made it though, def didnt have chicken strips after that ride, but the last time i enter a ramp at >80 with out leathers on
Yep, had a similar situation in a corner. Car was coming opposite direction and I was starting to run wide. If it hadn't been for track time, I would have let off the throttle in fear and subsequently taken out the car and myself. Instead, I gave it a bit more gas and looked deeper through the turn. Could feel the rear wheel slipping just a bit, but I didn't panic, just kept moving through the turn. Yes, I was shitting bricks (I bet the cage driver was too), but made it through due to a little bit of training and forum reading. Thank god for track time...
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Old 03-25-2008, 01:36 PM   #6
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Originally Posted by OTB View Post
...Conversly, slamming the throttle shut mid-turn in response to coming in too hot or making panicky mid-course corrections has just the opposite effects...... sudden unloading of the rear (and the decrease of traction that goes with lack of load), shortening of rake and trail (and the sudden quickening of steering that accompanies it) adding load to the front tire.

...Get your braking done early, and use a little positive throttle ALONG WITH A LITTLE BIT OF REAR BRAKE to encourage squat and the additional rear traction that goes with it.

Happy Riding
Going up Lookout Mountain, it's pretty much all throttle control. Coming downhill is a different story. There is this one section where you can come down a straight section around 60. This leads into a 15 MPH hairpin turn. The road is steep, crowned, and no shoulder.

I start braking, front and rear before the turn. I forgot, the road jogs to the right before it hairpins to the left. I also start leaning off the bike while I'm in the jog. I keep the brakes on in the turn. This probably goes against what every racer has said or written. But like OTB says above, if you go off the front brakes, the front rises and loses traction. You can't give it gas in this situation to load the rear, but with the rear brake on, the rear is loaded.

About seven-eights through the turn I let off the brakes and start giving it gas. It looks and feels so smooth. Like I've been doing it a thousand times. Actually, I have done it a thousand times. But I've seen bicyclists crash there, and I've stopped to move motorcycle fairing parts off the road.
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Old 03-25-2008, 10:23 PM   #7
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Going up Lookout Mountain, it's pretty much all throttle control. Coming downhill is a different story. There is this one section where you can come down a straight section around 60. This leads into a 15 MPH hairpin turn. The road is steep, crowned, and no shoulder.

I start braking, front and rear before the turn. I forgot, the road jogs to the right before it hairpins to the left. I also start leaning off the bike while I'm in the jog. I keep the brakes on in the turn. This probably goes against what every racer has said or written. But like OTB says above, if you go off the front brakes, the front rises and loses traction. You can't give it gas in this situation to load the rear, but with the rear brake on, the rear is loaded.

About seven-eights through the turn I let off the brakes and start giving it gas. It looks and feels so smooth. Like I've been doing it a thousand times. Actually, I have done it a thousand times. But I've seen bicyclists crash there, and I've stopped to move motorcycle fairing parts off the road.
That is why there is no substitute for experience. The book might say not to use the front brake in turns, but practical experience says that at times, not only might you do so, some times it is required. I, too have been on some truly gnarley, downhill, off camber nastiness that, if I followed convention and "common knowledge", I would have been off in the tooly bushes somewhere. That doesn't mean I grabbed a handful of front brake.......it does mean that I squeezed that lever with care and trepidation....
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Old 03-28-2008, 12:01 PM   #8
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Good info as always, my good man.
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The book might say not to use the front brake in turns
A lot of motoGP riders don't even start braking until they are IN the turn
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Old 03-28-2008, 12:10 PM   #9
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Seriously, we should have the OTB/No Worries reeducation thread. Always good reads from ya'll.
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Old 03-29-2008, 04:38 AM   #10
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Seriously, we should have the OTB/No Worries reeducation thread. Always good reads from ya'll.

not thread... Subforum... call it Knowledge... or School!

only they can start threads there...


awesome info
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