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Vehicles can be up to 10% off of stock settings, you can get a GPS to get actual speed if you want, not sure top speed of 750, but the thou won't register faster then 186mph.
 

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Not only is the speedo inacurate at thsoe speeds, but on a motorcycle the wind resistnce VS the weight of the bike will actually cause the back tire to be spinning at high speeds faster than you are going. AMA superbikes rear tires can actually spin up to 15 MPH faster than the bike is actually traveling at full speed.
 

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Thats very uncommon and on only extremely powerful bikes like ama superbikes.
 

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skibum91 said:
Thats very uncommon and on only extremely powerful bikes like ama superbikes.

Actually no.... not so. It is more about aerodynamics of a bike than its power.
Granted my 600 isn't going to spin it up that much, but 3-5 MPH would not be un-reasonable at all.

The coefficient of drag for a state of the art bike is actually close to the same as a common BUS. The most aerodynamic production bike today is the Hayabusa, and it is still VERY poor.

Vehicle Drag Coefficient
Description Low Medium High
----------------------------------------
Experimental 0.17 0.21 0.23
Sports 0.27 0.31 0.38
Performance 0.32 0.34 0.38
60's Muscle 0.38 0.44 0.50
Sedan 0.34 0.39 0.50
Motorcycle 0.50 0.90 1.00
Truck 0.60 0.90 1.00
Tractor-Trailer 0.60 0.77 1.20
The lower the number the better ;)
http://www.bgsoflex.com/airdragchart.html
 

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Well I can tell you out of all the bikes I have topped out I have never run into that problem.
 

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skibum91 said:
Well I can tell you out of all the bikes I have topped out I have never run into that problem.
And how exactly do you know this..... Do you have a precision calibrated speedometer, and a GPS to track your TRUE speed so you can compare your REAL indicated speed Vs. your REAL land speed ???? :hmmm:

It is not something you are going to notice, it just happens. ;)
 

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You don't think you are going to notice wheel spin, especially with some sort of cross wind?
 

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skibum91 said:
You don't think you are going to notice wheel spin, especially with some sort of cross wind?
Do a little experiment for me Ski..........

Assuming you have an interstate near you that the speed limit is 70MPH, go about 20 miles at about 80 MPH (in most areas 10 over the police will leave you alone right) and take a look at your back tire....... I guarantee you it will have about a half inch strip of blistered area right down the middle. Why do you think it does this? The front in your opinion is going the exact same speed, so theoretically shouldnt it be blistered equally :hmmm:

Your back tire spins faster than the front because of the large amount of drag a motorcycle creates, and the relatively light weight which provides for even poorer traction characteristics........ period....... end of story :thumbup:
 

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BallHawk3 said:
hmmm....how do you find out your true speed? get a book or search online and learn the gear ratios...then you'll be able to tell how fast your going by gear and rpm.....you can be a sick fuck like me :laughingr
A speedo healer or yellow box makes your gauges pretty damn close to the "true speed" that your tire is turning..... but if you were to use a very acurate GPS or LASER or something, It would be off, not much, but still off.

And the more power you get, the lighter the bike, and the faster you subsequently go (also taking gearing into consideration) the more slip you will get. It is a trade Motogp bikes have to make, light weight for agility, Vs top end speed and straight up traction.

Cornering is a whole different story
 

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Motojoe_23 said:
Do a little experiment for me Ski..........

Assuming you have an interstate near you that the speed limit is 70MPH, go about 20 miles at about 80 MPH (in most areas 10 over the police will leave you alone right) and take a look at your back tire....... I guarantee you it will have about a half inch strip of blistered area right down the middle. Why do you think it does this? The front in your opinion is going the exact same speed, so theoretically shouldnt it be blistered equally :hmmm:

Your back tire spins faster than the front because of the large amount of drag a motorcycle creates, and the relatively light weight which provides for even poorer traction characteristics........ period....... end of story :thumbup:
You don't think that blistered area has to do with the fact that its your rear tire thats pushing your bike, not your front?
 

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skibum91 said:
You don't think that blistered area has to do with the fact that its your rear tire thats pushing your bike, not your front?
Yes.......... that is exactly why, and it blisters because it is slipping pushing against the wind resistance...........why else would it blister? if it were turning the same exact speed as the front it would not blister, or they would blister evenly
 

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Motojoe_23 said:
Yes.......... that is exactly why, and it blisters because it is slipping pushing against the wind resistance...........why else would it blister? if it were turning the same exact speed as the front it would not blister, or they would blister evenly
That doesn't make any sense that it would blister the same as the front tire, the rear tire is the one with the force on it, The weight/power to move the bike is going to wear the rear tire down more than it would the front.

I understand the whole wind resistance/power thing that the bike can't go any faster but your not going to convince me that the rear tire is always spining the rear tire when moving. don't you think it would do the same thing in fast corners? well if your tire was spining faster than the rest of the bike it would try to step out on you everytime you leaned over.
 

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skibum91 said:
That doesn't make any sense that it would blister the same as the front tire, the rear tire is the one with the force on it, The weight/power to move the bike is going to wear the rear tire down more than it would the front.
That is my point, I was saying with your logic it would either be both or neither.
I understand the whole wind resistance/power thing that the bike can't go any faster but your not going to convince me that the rear tire is always spining the rear tire when moving. don't you think it would do the same thing in fast corners? well if your tire was spining faster than the rest of the bike it would try to step out on you everytime you leaned over.
ALL motor vehicles drive tires spin a bit faster than the vehicle is moving. This is why all vehicles drive tires wear faster than the driven tires
As far as fast corners go, the faster you go, and the more throttle you are applying, the more they will spin up. Typically you are NOT applying full throttle at TOP speed in a corner. That is when the spin is the greatest, and on high powered bikes like AMA factory or GP bikes, it can be as much as 15 MPH.
 

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Ski, Joe is right. It's all physics. I had a basic physics class in college and we talked about cars and why they hydroplaned. We also got into high speed driving. I had a really good teacher and he would try to make everything relative to something we could all understand.
 

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Damn... I was hoping someone would eventually come in and confirm what I am saying.

To brake it down more.... there are Two things that limit the top speed of a bike (or car for that matter) and that is wind resistance and traction. Horsepower has to overcome the resistance while the bike utilizes the available traction.

Eventually, as speeds increase, you inevitably run into a "wall" of air that the bike just cant push past. The light weight of our bikes lends then to having more HP than it can use to overcome aerodynamic drag causing lack of tra ction. It is now somewhat similar to your bike pushing against a real wall..... the more power you give it, the bike will eventually start to break traction to try and push the wall over in the direction you want to go.

bonneville racers face this more than anybody. Ever wonder why a turbo Hayabusa did 250+ MPH at the maxton mile (a mile long standing start drag race) but at the world spped trials in bonneville they have not gone much faster with a hayabusa with WAY more power and WAY more room to utilize tall gearing. It is all about traction, and bonnevilles traction sucks.

All the HP in the world cant overcome lack of traction or poor aerodynamics.
 
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