270kmh f3
#2
11-23-2006, 04:56 PM
RE: 270kmh f3
mods?
I don't think my F4 can do that... even if I include the speedoerror. :-/
I think the F4 runs out of revs before it can get to a true 270... different sprockets and it might be possible for me. I don't think it would. From my math, real world speed of 165 mph (265km/h) would be the rev limiter on stock sprockets for the F4... indicated could be 10% higher I suppose.
I don't think my F4 can do that... even if I include the speedoerror. :-/
I think the F4 runs out of revs before it can get to a true 270... different sprockets and it might be possible for me. I don't think it would. From my math, real world speed of 165 mph (265km/h) would be the rev limiter on stock sprockets for the F4... indicated could be 10% higher I suppose.
#3
11-23-2006, 05:01 PM
RE: 270kmh f3
Here's a strange thing...
I had my buddy check my speed the other day (AFTER he already pulled me over
, anyway, I told him about how I heard the speedo was of by 10 miles up from the factory.
So he agreed to check my speed as I was doing the limit and turns out, MY speedo is 5MPH SLOW exactly. I was doing 30 in second gear right by him for long enough that my speed didn't flucuate, and he checked my speed at 35MPH.
I thought everyone said that it was 10MPH fast?
Anyone else has a buddy in LE, have them check your speed. You might be surprised.
I had my buddy check my speed the other day (AFTER he already pulled me over
, anyway, I told him about how I heard the speedo was of by 10 miles up from the factory. So he agreed to check my speed as I was doing the limit and turns out, MY speedo is 5MPH SLOW exactly. I was doing 30 in second gear right by him for long enough that my speed didn't flucuate, and he checked my speed at 35MPH.
I thought everyone said that it was 10MPH fast?
Anyone else has a buddy in LE, have them check your speed. You might be surprised.
#5
11-23-2006, 05:13 PM
RE: 270kmh f3
It is off by a percent.
It is basically a rounding/accuraccy error.
The way speed is measured is by counting how many times the sensor detects a rotation TIMES the distance it think the bike travels for ever rotation. It's always the same error - it's a linear problem - the faster we go the more the error is noticed.
MATH of it all?
So say that it counted 20 rotations. It figures each rotation is 1.00 meters, where it is actually 1.05. Say it was measuring over 1 second.
So 20 * 1m = 20m/s = 72km/h.
Now if we correct it, it's really 20 * 1.05m = 21m/s = 75.6km/h
Using the 270km/h and the same error used above? It would indicate 270km/h when it was going 257.4km/h
Keep in mind the speedo error numbers I used in this EXAMPLE are 4.8%
---
After all the math - 270km/h no matter how you read it is damn fast...
It is basically a rounding/accuraccy error.
The way speed is measured is by counting how many times the sensor detects a rotation TIMES the distance it think the bike travels for ever rotation. It's always the same error - it's a linear problem - the faster we go the more the error is noticed.
MATH of it all?
So say that it counted 20 rotations. It figures each rotation is 1.00 meters, where it is actually 1.05. Say it was measuring over 1 second.
So 20 * 1m = 20m/s = 72km/h.
Now if we correct it, it's really 20 * 1.05m = 21m/s = 75.6km/h
Using the 270km/h and the same error used above? It would indicate 270km/h when it was going 257.4km/h
Keep in mind the speedo error numbers I used in this EXAMPLE are 4.8%
---
After all the math - 270km/h no matter how you read it is damn fast...
#7
11-23-2006, 06:34 PM
RE: 270kmh f3
ORIGINAL: woot
It is off by a percent.
It is basically a rounding/accuraccy error.
The way speed is measured is by counting how many times the sensor detects a rotation TIMES the distance it think the bike travels for ever rotation. It's always the same error - it's a linear problem - the faster we go the more the error is noticed.
MATH of it all?
So say that it counted 20 rotations. It figures each rotation is 1.00 meters, where it is actually 1.05. Say it was measuring over 1 second.
So 20 * 1m = 20m/s = 72km/h.
Now if we correct it, it's really 20 * 1.05m = 21m/s = 75.6km/h
Using the 270km/h and the same error used above? It would indicate 270km/h when it was going 257.4km/h
Keep in mind the speedo error numbers I used in this EXAMPLE are 4.8%
---
After all the math - 270km/h no matter how you read it is damn fast...
It is off by a percent.
It is basically a rounding/accuraccy error.
The way speed is measured is by counting how many times the sensor detects a rotation TIMES the distance it think the bike travels for ever rotation. It's always the same error - it's a linear problem - the faster we go the more the error is noticed.
MATH of it all?
So say that it counted 20 rotations. It figures each rotation is 1.00 meters, where it is actually 1.05. Say it was measuring over 1 second.
So 20 * 1m = 20m/s = 72km/h.
Now if we correct it, it's really 20 * 1.05m = 21m/s = 75.6km/h
Using the 270km/h and the same error used above? It would indicate 270km/h when it was going 257.4km/h
Keep in mind the speedo error numbers I used in this EXAMPLE are 4.8%
---
After all the math - 270km/h no matter how you read it is damn fast...
#9
11-24-2006, 04:48 AM
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#10
11-24-2006, 07:52 AM
RE: 270kmh f3
All motorcycles have this problem... even if it was perfectly accurate from the factory if you have the tire preasure, change the tire profile or drive on the freeway and wear the middle off - ANYTHING to make the tire a different size than the bike assumes it is. Counting the number of rotations is easy, getting the distance travelled in each rotation 100% accurate is nearly impossible. It could start out being exactly right and then start over reading... change tires and it under-reads.
Insted of risking under-reading EVER they over estimate the distance travelled in each rotation of the tire... which makes them even less accurate than they perhaps have to be.
GPS isn't a bad solution.