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Old 02-11-2014, 10:04 AM   #181
Tripped1
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Originally Posted by Wraith Rider View Post
The possible amount of acceleration with a given power and mass is a physical fact. You can't betray physics by changing the gearing.

Incorrect.

The torque applied to the rear wheel is VERY much affected by the gearing.

Whether or not the chassis will allow X amount of torque to be applied without rolling over backwards is a physical characteristic.
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Old 02-11-2014, 10:15 AM   #182
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@tkent02
If 6 seconds is as quickly as you could ever want, that's completely fine. It's just very slow.

@Tripped1
You don't need to know the torque or the gearing. Power tells it all. Of course you can change the gearing in a way that reduces the actual acceleration below what the power would allow, but you can't increase the possible acceleration that way.
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Old 02-11-2014, 10:18 AM   #183
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@tkent02
If 6 seconds is as quickly as you could ever want, that's completely fine. It's just very slow.

@Tripped1
You don't need to know the torque or the gearing. Power tells it all. Of course you can change the gearing in a way that reduces the actual acceleration below what the power would allow, but you can't increase the possible acceleration that way.
You sir, once again, are completely clueless.
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Old 02-11-2014, 10:21 AM   #184
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Originally Posted by Wraith Rider View Post
@tkent02
If 6 seconds is as quickly as you could ever want, that's completely fine. It's just very slow.

@Tripped1
You don't need to know the torque or the gearing. Power tells it all. Of course you can change the gearing in a way that reduces the actual acceleration below what the power would allow, but you can't increase the possible acceleration that way.
Yes you can.

The primary drive, transmission, and final drive are ALL torque multiplicative.

Power is work

W=Fd (force times distance)
That that force is torque, SO if you are increasing the multiplicative effect of the final drive you are making the F in the equation greater. The actual power derived from the engine is a secondary concern.

Engine output as an absolute only matters if you are direct drive, there are NO internal combustion power motorcycles that I have seen that are direct drive.

This how you can move warships with jet engine that spool up to 16,000 RPM. The shafts may be doing 20rpm, but you crank HUGE power and no torque down to HUGE torque with the main reduction gear.
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Old 02-11-2014, 10:24 AM   #185
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Originally Posted by Wraith Rider View Post
You don't need to know the torque or the gearing. Power tells it all. Of course you can change the gearing in a way that reduces the actual acceleration below what the power would allow, but you can't increase the possible acceleration that way.
Time to bring the facepalms in.
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Old 02-11-2014, 10:28 AM   #186
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Originally Posted by Wraith Rider View Post
@Tripped1
You don't need to know the torque or the gearing. Power tells it all. Of course you can change the gearing in a way that reduces the actual acceleration below what the power would allow, but you can't increase the possible acceleration that way.


Engine power is torque times angular velocity. Saying torque has nothing to do with power is fundamentally incorrect on the most basic level. Gearing also has a profound influence on the rate at which force can be applied to the drive wheel.

You seem to be trying to make a physics argument without actually understanding the physics. Better to just state that you LIKE "high" power. That is a subjective statement that no one can objectively argue against. But bringing in absolutely incorrect physics to bolster your opinion does your argument a disservice.
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Old 02-11-2014, 10:29 AM   #187
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a[m/sł] = P[kW] / (m[kg]*v[m/s])

You will NEVER achieve higher acceleration than determined by power and mass as shown in this equation. No matter what you do with your gearing. It's just impossible and it's plain physics. Face it.
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Old 02-11-2014, 10:33 AM   #188
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Since I value speed in the curves much more than speed down the straights, this is pretty much irrelevant to me. If one bike is capable of a 10.5 sec quarter, and another 11.0 secs, or even 12. Does it really matter very much unless you are on the race track?

The only time I really miss having big power is when I get stuck behind a sport bike rider who twists the throttle on every straight but has no clue on how to go around the curves.

The problem with big power is that along with big power you generally have either a big heavy bike, or an uncomfortable super sport bike. That's fine if that's what you want but it's not for me.
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Old 02-11-2014, 10:34 AM   #189
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The power in your equation must be measured at the point it is applied (the rear wheel). The power applied at the rear wheel is a function of the engine torque, the engine speed and the gearing.

If this were not true your bike would be able to accelerate from 0-60 just as quickly in 5th gear as you can in 1st gear. Don't take my word for it. Get a stopwatch and measure acceleration in these two scenarios.
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Old 02-11-2014, 10:36 AM   #190
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I thought there would be no math today.





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Old 02-11-2014, 10:38 AM   #191
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I thought there would be no math today.

you were wrong.



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Old 02-11-2014, 10:40 AM   #192
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BRB...


You're right.

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Old 02-11-2014, 10:45 AM   #193
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BRB...


You're right.

OK, which hand is faster, the hand with the big numbers or the one with the small numbers?
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Old 02-11-2014, 10:45 AM   #194
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@Paebr332
As I already stated, a bike CAN of course be geared to accelerate less than possible with a given power, but NOT to accelerate more than that. And of course the power in the equation is the power applied, what else could one think it could be? But you can NOT apply more power than the bike has. No matter the gearing.

Quote:
Originally Posted by klaviator View Post
If one bike is capable of a 10.5 sec quarter, and another 11.0 secs, or even 12. Does it really matter very much unless you are on the race track?
Well to me 1g of acceleration just feels better than 0.5g of acceleration. It's an adrenaline thing I think.
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Old 02-11-2014, 10:47 AM   #195
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@Paebr332
As I already stated, a bike CAN of course be geared to accelerate less than possible with a given power, but NOT to accelerate more than that. And of course the power in the equation is the power applied, what else could one think it could be? But you can NOT apply more power than the bike has. No matter the gearing.



Well to me 1g of acceleration just feels better than 0.5g of acceleration. It's an adrenaline thing I think.
With appropriate gearing, that DR 200 would do 1g of acceleration, or a lot more. Just not very far.
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