Oh, and GPS speedometers are only as accurate as their scan rate. So, if they scan once every five seconds for their position, you have to hold whatever speed you have for five seconds to ensure an accurate reading. They're pretty accurate, but even the SpeedoHealer can correct to under 1%, and at 200mph, that's less than 2 mph. Not bad, I think.
how many 200 mile per
- Thread starter orangebusa??
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Scan rates are generally 1 second on any GPS unit.... and at terminal speeds, it's not like at 50mph where the speedo just jumps 30mph in 3 seconds... at terminal speeds you're lucky if you gain 0.2 mph in 1 second. You'll top out before you let off... giving you that 1 second for the GPS to register.
As for slippage at high speeds... that's where you get most of the the tire/clutch slippage.
Think about it.... at those speeds the bike is so light and the rear wheel is moving at super high speeds. Believe me... it's not aero's that effect the speed at any given RPM...
Just try it with a GPS..... gear the bike 16/40 and see what the GPS reads when you bang off the limiter in 6th.
I'm betting you don't see anything higher than 185mph on the GPS.
btw... not to poke fun, but it's "aerodynamics"
As for slippage at high speeds... that's where you get most of the the tire/clutch slippage.
Think about it.... at those speeds the bike is so light and the rear wheel is moving at super high speeds. Believe me... it's not aero's that effect the speed at any given RPM...
Just try it with a GPS..... gear the bike 16/40 and see what the GPS reads when you bang off the limiter in 6th.
I'm betting you don't see anything higher than 185mph on the GPS.
btw... not to poke fun, but it's "aerodynamics"
I agree with you. If you use 16/40, at the rev limiter, you're only going about 185. Two things: 1.) Dip into the red (beyond the rev limiter... which I do routinely, thanks to the TRE), and you'll go a little faster (193 mph at 11,000), and 2.) Given 18/40 gears, you'll lose a lot on the low side, but gain a great deal on the high end. That's been my whole argument... and while there's going to be some minimal slippage, I contend that the greatest limiting factor is the wind resistance (cavitation at high speeds... part of limitations of having any amount of drag coefficient).
I think you may be unclear about what I'm saying...
The rev limiter is not altered by the TRE.... the timing which allows you to pull to the rev limiter is what is altered by the TRE.. hence the name, "Timing Retard Eliminator".
There is a difference between the Redline and Rev limiter.
Redline- Begining of the red zone
Rev Limiter- point at which your ECU stops the RPM's (it's well beyond the redline)
Now what I'm saying is that the MPH at the Rev Limiter is going to be roughly 182mph... if you're using a slightly taller tire with a lot of air, it may allow for 184-185mph at best... ON THE LIMITER.
With 18/40 gearing... you're looking at 208mph on the limiter (assuming your bike can pull it).
That's all I'm saying.
Of course the wind resistance is the largest factor stopping you from achieving those speeds.... I'm not talking about that. I'm talking about the maxium mph that a certain gearing combination will allow at the rev limiter.
You can have 10,000,000 rwhp.... but if you're geared for only 180mph at the rev limiter in 6th..... you'll only do 180mph.
The rev limiter is not altered by the TRE.... the timing which allows you to pull to the rev limiter is what is altered by the TRE.. hence the name, "Timing Retard Eliminator".
There is a difference between the Redline and Rev limiter.
Redline- Begining of the red zone
Rev Limiter- point at which your ECU stops the RPM's (it's well beyond the redline)
Now what I'm saying is that the MPH at the Rev Limiter is going to be roughly 182mph... if you're using a slightly taller tire with a lot of air, it may allow for 184-185mph at best... ON THE LIMITER.
With 18/40 gearing... you're looking at 208mph on the limiter (assuming your bike can pull it).
That's all I'm saying.
Of course the wind resistance is the largest factor stopping you from achieving those speeds.... I'm not talking about that. I'm talking about the maxium mph that a certain gearing combination will allow at the rev limiter.
You can have 10,000,000 rwhp.... but if you're geared for only 180mph at the rev limiter in 6th..... you'll only do 180mph.
Well, yes... and then I dip down into the red. The rev limiter cuts in somewhere near 12,000 or 12,500.
I guess I just see differently, that's all. My bike doesn't even hit the red zone until 10,800 and if I'm dipping below that (and yes, before the rev limiter), I'm still pulling... ie, going faster. If I have 18/40 gearing and I'm at 10,800... AND... I'm treadmill (ie, no wind resistance), the rear wheel will be travelling at abut 210mph.... before it hits the red at all. If I dip below the red line, I'm still going faster, still pulling, because the rev's are continuing to go up ... the engine still has more to give. It might not be particularly healthy long-term, but there it is. Now, put in the wind resistance and the realistic probabilities are decreased, but if I'm at the red line (not the rev limiter) and have 18/40's, I'll definitely be going faster than 200mph... as the gearing and the size of the tires will dictate. If wind is preventing me from hitting 10,800 then that's a factor preventing me from doing it, but if I do hit 10,800 with those gears, I would be going about 208-210.
By the way, went to Teledo on Sunday. There was a poker run. I ran up there from Fort Wayne with about ten other guys. It was pretty cool. We were running with a bunch of locals. When we got on the highway we managed the traffic better than most of the bikers. Only one local was keeping up to us Fort Wayne guys, but we do a lot of that kind of thing on 469 and 69, so we probably had an unfair advantage. We blasted back home and ended up having a really good time. If anyone is interested, they have it every year. About 100-150 sport bikes do the run in Toledo this time every year.
It may INDICATE 12,000 but the ECU regardless of a TRE makes your TRUE RPM revlimiter at 10,800 - hence the reason DAVEO does an ECU mod on Busa ECU's and some models will not be adjustable beyond 11,200... Period...
With 18/40 gearing at the rev limiter (whatever it is on the Busa)... you WILL be going 208mph assuming you don't have excessive clutch/tire slippage.
But to pull that sort of MPH... you need major power!
If you're a small light guy and an experienced land speed racer.... you'd need roughly 210-220rwhp to pull that gearing.
Assuming you've listed all your mods.... I don't see your bike doing much more than 194-196mph depending on your weight, tuning, weather.
If you put such tall gearing on your bike... YOU WILL GO SLOWER!!!!!!!!!!!!!!!!!!!!
Gearing the bike that high would put you well under your peak power at those 185-190mph speeds... and your bike will simply not be making enough power at that RPM to continue pulling.
The trick is to gear the bike so that you're just beyond peak power when you top out. This way, you know you're making as much power as possible at the point of greatest wind resistance.
All 18/40 gearing is going to do is leave you with LESS power to combat the wind resistance at 190mph.
But to pull that sort of MPH... you need major power!
If you're a small light guy and an experienced land speed racer.... you'd need roughly 210-220rwhp to pull that gearing.
Assuming you've listed all your mods.... I don't see your bike doing much more than 194-196mph depending on your weight, tuning, weather.
If you put such tall gearing on your bike... YOU WILL GO SLOWER!!!!!!!!!!!!!!!!!!!!
Gearing the bike that high would put you well under your peak power at those 185-190mph speeds... and your bike will simply not be making enough power at that RPM to continue pulling.
The trick is to gear the bike so that you're just beyond peak power when you top out. This way, you know you're making as much power as possible at the point of greatest wind resistance.
All 18/40 gearing is going to do is leave you with LESS power to combat the wind resistance at 190mph.
I got the power.... I just need to know what gearing I need to go that fast.
You may be right. I'll find out one way or another. It's only costing me $14 for the 18 front. I'll ride it as fast as it goes, use the Yellow Box and prob get a friend cop to radar me. That'll be the definitive proof for me. I'll cap the bike out using the gearing and get the reading.
Cheers all.
Cheers all.
Can you recommend any relatively inexpensive ones... and would it record fastest speed? Thanks.Just get a GPS and zip tie to the upper tripple...::
Phantom12,
FYI, GPS scan rates are 1000 times per second, but the display only updates every second. (Much better than the suggested 5sec interval)
Imagine if the display changed 1000 times per second, then trying to read it at 200mph :-)
And the best thing about a GPS speed is it accurate and is directly comparable with any other GPS speed. Unlike the Suzuki speedo.
I've hit a measly 181mph on the GPS, but had to back off as it was pitch black at 3am one night. Too much traffic in the daytime and few straight roads where I live. Hitting 180 on the Speedo is easy as that's only 161.1 real. Much quicker to get there and back down to say 100 than it is to wait for top speed to arrive.
In the meantime, it's good to come here and read about others doing 200+
Steve
It's nice to see alot of honest people on this thread. If you read some threads or other sites you'd swear that all busa owners have been 200+ and if you havn't then you can't ride.
There are so many variables in going fast. You must try to solve each one.
I've been 165 on the gps with the speedo reading 186. So to solve the error I've ordered the speedohealer.
To go faster I need a longer road and we've been scoping that out.
To help "I really don't know what."I've just put in a power commander.
To help the restricter, I just put in a TRE.
Now alls I need is a new tire and an opportunity.
There are so many variables in going fast. You must try to solve each one.
I've been 165 on the gps with the speedo reading 186. So to solve the error I've ordered the speedohealer.
To go faster I need a longer road and we've been scoping that out.
To help "I really don't know what."I've just put in a power commander.
To help the restricter, I just put in a TRE.
Now alls I need is a new tire and an opportunity.
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