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Discussion Starter · #1 ·
I was curious myself so I entered all the specs from the owners manual into a calculator. He's a screen shot for you guys.



You guys that are making top speed test runs, what gear are you in 4th, 5th?
 

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Saratogian
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6th gear, man. You put shit in, you get shit out...you must be off slightly on a number somewhere. For starters, our true redline is probably closer to 13500. What does the "select preset" drop-down do?
 

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All it means is the bike can physically do 169 in 6th gear with the gearing and redline, but it doesn't have the HP to make it that high.

In reality, it seems to me once you get to about 130mph actual, there's not much difference in 5th and 6th gear acceleration. I saw 154 indicated (probably 140 actual) in 5th gear, still pulling a little.

Do you have a link to that site? Do they have any other calculators?
 

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Discussion Starter · #4 ·
DefyInertia said:
6th gear, man. You put shit in, you get shit out...you must be off slightly on a number somewhere. For starters, our true redline is probably closer to 13500. What does the "select preset" drop-down do?
Why are those numbers shit? They look dead on to me... I used the exact numbers from the service manual.

6th gear is geared for 169mph, you just don't have the horsepower to get there. That is why for top speed runs your probably not in 6th gear, most likely 4th or 5th... The lower the gear the more power gets to the ground.

The redline on my 2007 is 14,000 rpms, not sure why your is lower. I think I remember reading somewhere the the rev limiter kicks in at 14200 rpms

here's the link to the site if you want to play around...

http://www.bikerenews.com/Stories_Archives/GearRpmSpeedCalculator.htm
 

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Saratogian
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omniphil said:
Why are those numbers shit? They look dead on to me... I used the exact numbers from the service manual.

6th gear is geared for 169mph, you just don't have the horsepower to get there. That is why for top speed runs your probably not in 6th gear, most likely 4th or 5th... The lower the gear the more power gets to the ground.

The redline on my 2007 is 14,000 rpms, not sure why your is lower. I think I remember reading somewhere the the rev limiter kicks in at 14200 rpms

Only because 14K or 14.2K is your indicated RPM...the dyno would likely tell a different story.

The bike pulls through 4th (for me anyway) and I've used 6th at the track (Road America) but maybe I should have kept it in 5th...not sure...I was looking at the quickly approaching right-hander, not the tach.
 

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Discussion Starter · #6 ·
DefyInertia said:
Only because 14K or 14.2K is your indicated RPM...the dyno would likely tell a different story.

The bike pulls through 4th (for me anyway) and I've used 6th at the track (Road America) but maybe I should have kept it in 5th...not sure...I was looking at the quickly approaching right-hander, not the tach.
Maybe your dyno is lying? :)

I suspect your were traveling below 140mph, and in that case, yeah, you'd have more power to the wheels in 5th...
 

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Discussion Starter · #9 ·
DefyInertia said:
It's common knowledge that sportbike speedos and tachs are optomistic. Are you familiar with the R6 17.5K bs?
I'm not talking about the tach.

The engine computer has a redline built into it, when that redline is hit the rev limiter steps in, that has nothing to do with the tach. The tach as accurate or inaccurate as it may be only displays what it gets from the computer.
 

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Saratogian
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omniphil said:
I'm not talking about the tach.

The engine computer has a redline built into it, when that redline is hit the rev limiter steps in, that has nothing to do with the tach. The tach as accurate or inaccurate as it may be only displays what it gets from the computer.
If you got your number (14K+) from the manual or some other yamaha publication it should be close to the number that the tach reads but not the speed at which the engine is actually spinning....the dyno would reveal the most accurate number.

In other words, the "engine computer" limits the revs to less than 14K per those who have tested it. Get it? Got it? Good...
 

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Saratogian
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fxclm5 said:
hey those 1-3 r pretty much dead on, so 3/6 aint bad... but thats with speedo error and the tach error working 2gether... so what is it u guys r arguing about?
His program spits out actual numbers. When I bounce of the limiter in 2nd gear I'm not actually doing 94 but I would be - according to his output - if the engine was spinning at 14K...obviously it's not.

EDIT - stock gearing
 

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Discussion Starter · #13 ·
DefyInertia said:
His program spits out actual numbers. When I bounce of the limiter in 2nd gear I'm not actually doing 94 but I would be - according to his output - if the engine was spinning at 14K...obviously it's not.

EDIT - stock gearing
The speedo is probably off then :) Maybe verify with GPS?


This is the internet, we are arguing about completely useless stuff because, ummm, that's what you do on the internet? :)

:popcorn
 

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DefyInertia said:
His program spits out actual numbers. When I bounce of the limiter in 2nd gear I'm not actually doing 94 but I would be - according to his output - if the engine was spinning at 14K...obviously it's not.

EDIT - stock gearing
ok so we both agree that the speedo and tachometer is not what actual reality is right? problem solved, so whatever # ur pitching against his # doesnt even matter cuz they are all not accurate due 2 our original hardware not being accurate. other then that those 1-3rd gears redline is correct for me, ive never redlined 4th..or 5th or 6th so i dunno
 

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The Tach reads 14K at redline but the engine is spinning closer to 13K at that point. My cars are the same way...on my Prelude for instance fuel cutoff is at 7,600 rpms but the tach shows it rpms at 8,400 at the fuel cut. Same sorta thing with the bike. The tach is optimistic. All manufacturers have to keep up with the optimism or the general public would think one of them is a dog! "13K rpms, well my tach says it goes to 14K!"

Damn marketing is all it is! Not sure how exactly they get away with it but I digress.

It is pretty cool that this bike will exceed most posted limits in 1st gear. :)
 

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fxclm5 said:
hey those 1-3 r pretty much dead on, so 3/6 aint bad... but thats with speedo error and the tach error working 2gether... so what is it u guys r arguing about?
So basically you were saying that it's dumb luck that 1-3 per the program are close to 1-3 per our bike even though they are both wrong? If so, then yeah, I agree. Omni was trying to say that the limiter kicked in around 14K or 14.2K when in fact it is significantly lower.

Someone should run that program using 13K and then 13.5K just for kicks....at least then we'd have a better idea of what the top speed would be sans wind resistance.
 

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Well, Omniphils calculation seems to be spot on. The 14k readline is just a number in the calc and does not mean that any of our FZ6 actually reach that readline. As far as I know the true readline is closer to 13 kRPM. The numbers are just theoretical, if our bikes would get to 14 kRPM on the 6th we would be going 169 mph. But as we all know the hp is just not enough for this speed.

Anyway, it was nice to have this data calculated (Java Script somewhere?). Speedo error has nothing to do with this. It is very easy to measure RPM accurately, but true speed is a different thing. I trust the tach but not the speedo. For me 7000 RPM and indicated cruising speed of 84 mph is what I want to know. That will keep me just within the speed limit.
 

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Holy drama kids! You would think this is an octane thread...

I wrote a calculator thingy a while back. If you use the gearing info for our bike, this should output actual speed for any given actual RPM, regardless of whatever the friggin' display might say. Don't discount tire wear as a significant fudge factor, either. 2 inches circumference difference (which is about 1/3 inch tire wear) makes a pretty significant difference...
 
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