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Discussion Starter #1
While back we had some threads going out top speeds of bikes.

Anyhow my buddy has a 2001 and I a 2002 GSXR750. Both bikes same mods, Devil pipe, KN, +2 rear sprocket. Mine has a TRE, not sure if he does or not.

Anyway the "indicated" speed that both of our bikes would pull was a maximum of 186mph with this gearing. The tac would lay stone still right just at the red as the speed would just sit rock still at 186mph.

These runs were done over a good 10 mile plus span of road. We both kept the bikes nailed full open throttle 6th gear for appox 3 minutes at the speed with no change. Did it a few times north, few times south with same affect.

A friends 2004 GSXR1000 with same mods as our 750's had virtually no extra top speed pull. Had some but nothing "too" noticed. He would catch us but the gain he would pull was so, so very slight. For instance it would take him 10 seconds or more to pull even a bike length at max speed.

My guess is we were in the low 170's range. for actual speed. But 186 is all she would click to, no more.
 

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I did the same thing last summer on my 2000 GSXR750 with a +2 rear and other minor stuff. I used an empty 5 mile stretch. At 14k my speedo said 185. I held the speed for about 45 seconds.
 

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Discussion Starter #3
Yeap, thats all she wrote.
 

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He Who Touches Himself
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I heard that the 750's and 1000's were governed at 186mph. Does anyone know how to figure how much the speedos are off the faster we go?
 

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from what i understand all of the japanese sportbike companies agreed to set the max top speed at 186. this is not a gov't rating, they did it on their own for safety. so no matter how fast you are really going if the bike thinks you are doing 186 then it should go any faster.
 

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Discussion Starter #6
Well the speedo is off a set % so you can do the math. Depends on your gearing change also. For instance 55mph may really only be 50, 110 may only me 100. Its a set % across the boards.

From the reading ive done the Suzuki's are governed the highest at 186 with Honda and Yamaha both being lower 180's, don't know about Kawis

But the 750 is only 170's, not 180's as far as actual speed.

Yea there are ways around it, but really not needed ya know. 170 is hella fast anyhow.
 

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from what i understand all of the japanese sportbike companies agreed to set the max top speed at 186. this is not a gov't rating, they did it on their own for safety. so no matter how fast you are really going if the bike thinks you are doing 186 then it should go any faster.
Not arguing whether there is a 186 limit or not (But only the 1000 has a 186 speed limiter and it can be overridden with a 6.8K ohm resistor. It works by cutting fuel to the #2 injector. and is only activated in 6th gear.) however, your statement on why they would have put a limit at 186 makes absolutely no sense.

They put a limit at 186 mph for their own safety??
Please explain how that provides safety for anyone.

Out of the box measured top speeds in descending order. Only one magazine's numbers though (And not a very good one at that). The numbers

04 ZX10R --------- 186
04 R1--------------- 184
04 GSXR 1000 ---- 180
CBR 1000R-------- 175
00 GSXR 750------ 172
 

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Discussion Starter #8
Pretty sure what he meant by the reasoning behind the bike makers caping max speeds on their own without too much world wide intervetion was to cover it before it got to the point of the governments restricting imports. As we all recall the late 1990's early 2000's when the Busa, CBR1100 and then the ZX10 the max speed wars were in the works. Early busa's had a speed that would spin up to 220mph.

I think the bike makers realized if they don't cap things the governments would and that would equal lost sales.

Busa's and GSXR1k's both have the max speed limiter that the TRE can bypass. That said this does not mean the bike is capable of much more maximum speed.

My GSXR750 flicks the speedo up to an indicated 186mph.....prob low 170's.......and thats it. The bike is limited by aerodynamics and motor. More motor will get it into the 180's or more just as the guys racing at Daytona are able to get the 1000's of each make up to very close to 200mph these days.

What i can add is Honda DOES seem to have a lower limited speed than most others. My GSXR750 will maximum speed walk from CBR929's and for the most part flow with a 954 or even creap from it. Had not done the test with a 1000RR.

As said, regarless 170 is pretty damn fast .......and quite fast enough. Even on a barren stretch of 5 lane highway i sweat going that fast for more than a few miles.
 

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Pretty sure what he meant by the reasoning behind the bike makers caping max speeds on their own without too much world wide intervetion was to cover it before it got to the point of the governments restricting imports. As we all recall the late 1990's early 2000's when the Busa, CBR1100 and then the ZX10 the max speed wars were in the works. Early busa's had a speed that would spin up to 220mph.

I think the bike makers realized if they don't cap things the governments would and that would equal lost sales.

Busa's and GSXR1k's both have the max speed limiter that the TRE can bypass. That said this does not mean the bike is capable of much more maximum speed.

My GSXR750 flicks the speedo up to an indicated 186mph.....prob low 170's.......and thats it. The bike is limited by aerodynamics and motor. More motor will get it into the 180's or more just as the guys racing at Daytona are able to get the 1000's of each make up to very close to 200mph these days.

What i can add is Honda DOES seem to have a lower limited speed than most others. My GSXR750 will maximum speed walk from CBR929's and for the most part flow with a 954 or even creap from it. Had not done the test with a 1000RR.

As said, regarless 170 is pretty damn fast .......and quite fast enough. Even on a barren stretch of 5 lane highway i sweat going that fast for more than a few miles.

You are probably right about why the top speed was limited at 186.

Actually the fastest stock busa measured top speed was 196 mph (99). To go 220 the bike would have to have had over 200 hp

I would say that if you have +2 on the rear sprocket you are more likely going around 160 at an indicated 186 on your bike.
 

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He Who Touches Himself
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The speed restrictions from the factory came from the different govt. agencies in Europe. It was one of those deals where they said, "If you don't do something, we will." So Suzuki and the rest took it upon themselves to do the "governing". Makes sense when you think about it, if they didn't do it, them the govt. could have made them set it at a much lower speed.
 

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Discussion Starter #11
I honestly don't think the +2 took any top speed off the bike. I do know it is faster than 160. Being most 600's will go in the 155 range and im WAY ahead of them. And stock CBR929's, etc will go up near 170 and im ahead of them also. Ill have to get a GPS but i think the bike pulls just as fast, just higher in the rpm range.

I know a busa won't go 220 , but the mear fact that its speedo had those numbers was fuel for the fire of the anti bike people. So, easy fix, just change the cluster.
 

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Pretty sure what he meant by the reasoning behind the bike makers caping max speeds on their own without too much world wide intervetion was to cover it before it got to the point of the governments restricting imports. As we all recall the late 1990's early 2000's when the Busa, CBR1100 and then the ZX10 the max speed wars were in the works. Early busa's had a speed that would spin up to 220mph.

I think the bike makers realized if they don't cap things the governments would and that would equal lost sales.

Busa's and GSXR1k's both have the max speed limiter that the TRE can bypass. That said this does not mean the bike is capable of much more maximum speed.

My GSXR750 flicks the speedo up to an indicated 186mph.....prob low 170's.......and thats it. The bike is limited by aerodynamics and motor. More motor will get it into the 180's or more just as the guys racing at Daytona are able to get the 1000's of each make up to very close to 200mph these days.

What i can add is Honda DOES seem to have a lower limited speed than most others. My GSXR750 will maximum speed walk from CBR929's and for the most part flow with a 954 or even creap from it. Had not done the test with a 1000RR.

As said, regarless 170 is pretty damn fast .......and quite fast enough. Even on a barren stretch of 5 lane highway i sweat going that fast for more than a few miles.
that is exactly what i meant.
not sure if i sounded like i said our safety, but i meant the manufacturers safety as in financial
 

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Just my two cents but here is what i have heard...

I believe it agrees with what a lot of people have said, and i hope i am not being redundant. When you gear your bike (and even completely stock bikes have optomistic readings) the speedo is ALWAYS off at/around top speeds (whether it be by a single mph or 15mph) When you gear your bike the curve for how far off your speedo is from actual speed is exponential (thus making a curve and not a linear slope) This means that at 20mph it may be of by like .?? and then at 100mph it could be 7mph off. Now i know someone already expressed this but i just wanted to make it clear that the curve for speedo inaccuracies is EXPONENTIAL.

Now to the idea of aerodynamics... Whoever said it was exactly correct! Aerodynamics is the biggest pitfall for bikes, believe it or not. i read an article (not sure what mag?) that was working on a 200? Hyabusa 1300R... and $250,000 later they got the bike up to 225mph... completely stock. Now what i mean by completely stock is all they did was a shit ton of windtunnel testing, removed the top speed limiter, and dropped like 40 lbs by adding CF everything possible. Basically just a stock motor (now its been like 2 years since i read this article so PLEASE anyone who has seen it or posses it, correct me if need be!). This speed was not read off the stock speedo obviously. Later in the article they claimed that in some/most cases in order for a bike to go from 190 max to breaking 200 mph... can take excess of 60 hp simply becuse of aerodynamics. This explains why some company/person dropped that much into a "stock" busa to run it around 225mph.

Once again, just my .02 and thanks for reading...
 

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Actually the fastest stock busa measured top speed was 196 mph (99). To go 220 the bike would have to have had over 200 hp


the 1st busa would indicate 220 on the speedo stock, but yes the actuality is it was only going in the 180's-190's

my stock geared GSXR 750, hits 141 on the speedo at the end of the 1/4, but the time slip read 126
 

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I am an amature as far as tech stuff goes. I have a 2000 750. I had it dynoed after adding an ignition advancer and with the stock gearing the dyno showed 174mph while the speedo showed 186mph. This past fall I changed the gearing for top speed. I used the stock front (17 tooth) and made the rear a 39 tooth. This was the only change that I made to the bike since my last run. With the 39 tooth the dtno run showed a top speed of 189mph. Unfortunatly I forgot to check the speedo reading this time, but I bet that it showed 186mph. Within a week or two, I am going to make another dyon run. This time should be faster with another sprocket change (18T front , 39T in back). I'll try to remember to check the speedo during this run.
 

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Gsxr 750's will not go faster than 170 mph! (unless highly modified) just cause the" speedo says" specialy when you are geared...(the speedo runs off of the counter shaft) the best one I heard was "my bike will do 190 mph" when asked to prove this great task it was learned that his speed run was done on a swingarm stand in the garage
sorry for the rant I am just sick of super speed claims based on geared bikes....my bike goes 220 mph oh yeah its got a 56 tooth rear sprocket.......
 

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Did not mean to upset anyone, sorry. I really had that speed, but like I said it was on the dyno, not the street. The street would not have been as fast (weight/ air friction). BTW, a 56 tooth sprocket would give you a quicker 0-60, not top speed. You should watch what you complain about and do more research first. No offence.
 

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Did not mean to upset anyone, sorry. I really had that speed, but like I said it was on the dyno, not the street. The street would not have been as fast (weight/ air friction). BTW, a 56 tooth sprocket would give you a quicker 0-60, not top speed. You should watch what you complain about and do more research first. No offence.
true but what would the speedo say? I am sorry about that post note the post time.....my point was when you gear down your bike the speedo will read faster, and it wasn't quite directed at you. some people don't understand that the speed sensor runs off of the countershaft
 

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No prob 2step. I agree with you. When I dropped teeth on the front the first time I took my bike down a nice staight away and the speedo showed 175mph. There is no way my bike was going that fast. I'm guessing it was more like 150 or something. I am a speed freak none-the-less. I'm setting up now for high speed runs, but once doone with that, it is off to the 1/4 mile. I'm learning quite a bit about gearing lately.
 
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