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speedo stops at 186mph however your not really going that fast, the stock speedo is so far off that it aint funny...
 

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Yeah thats why I noted it was indicated, it seems really optimistic, but it is fun to see the speedo just blur thought the triple digits. I'd like to see someone try a top end run with a GPS unit.
 

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I've read that the K4 speedo with stock sprockets (17/42) is around 8% - 10% off. Running 16/44 sprockets is supposed to get it closer too reality, so now 178 mph is at redline in 6th gear. I did however, read this in an ad for a 520 conversion kit...
 

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I've read that the K4 speedo with stock sprockets (17/42) is around 8% - 10% off. Running 16/44 sprockets is supposed to get it closer too reality, so now 178 mph is at redline in 6th gear. I did however, read this in an ad for a 520 conversion kit...
this is a completely incorrect statement, and whomever told you that was lying to you. 16/44 is -1, +2, and it makes it an even higher percentage than stock. i would guess between 20% - 25% error.

the only way to tell how much your speedo is off (and yes, it does vary from bike to bike) is to either get a gps and measure from there, or find one of those roadside radar stands that say "speed limit xx, your speed xx".
 

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Well.... today my speedo bloked at 299kmh and the rpm still climbed a litle bit. I rode with the speedo blocked for some minutes.... and then I backed of because I was running out of gasoline.
This was in 5th gear..... I dont recall what rpm I was doing.... however it was never necessary to put 6th gear. My bike is stock.
 

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yeah doohan, i think it was th may issue of bike. they said like 175 in 4th, 185 in 5th and then the speedo stops at 186.... i wonder what they hit if u bypass it.
 

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would be nice to see speedo past 200 mph for a laugh. Heine Gericke do a bolt on speedo that goes uo to 320 kmh,think you have to weld magnet pick-up onto wheel tho.
 

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Wonder how fast it will go when I'm out of the break in period.
Plenty fast. As fast as your gears and ultimately the power of the engine and aerodynamics will allow. It is my personal believe that the speed restriction is limited by gearing, engine power and the rev limit. Not some mysterious ignition cut-off at 186 mph in 6th gear. Sorry TRE guy's but that's the reality unless someone can convince me otherwise.

186mph indicated just happens to be the calculated limit of the speedometer, not sure of actual speed the stock gears and the rev limit will allow. If you read the magazine tests you will see trap speed determined by radar (usually accurate within a few mph) is well over the indicated error limit that 189mph on the speedo would actually represent. Which would be a speed of 170mph @ -10% error.

Sport Rider Speed Tests done with Radar on the K4 was 180 mph. That would be 186 @ 3% error rate but 3% seems low. I would think the error of 186 mph indicated if reached would mean much less speed than 180mph actual.

The '04 ZX10R had a trap speed of 186. Given both bikes hit the indicated limit before the actual speed limit was achieved it is fairly certain that would indicate the final drive gear ratio and the rev limit supersedes the speedometer indication.

Given the well know indication error rate is usually more that 3% for the GSXR and 2% for the ZX10R the speed limit by speedometer indication is unlikely.

As far as I'm concerned it seems apparent that the speedometer is programmed to stop at 186mph or 299kph but in my opinion it is not involved with the ECU and speed limitation of the bike.

Curious if anyone has ever increased the stock final drive gear ratio (taller) without altering anything electronically and then used a GPS or alternate speed indication to see your speed limit?

The TRE would then seem only useful in changing the ignitions full advance when you want it on full time regardless of gear position and the top speed restriction is not an issue regarding the GPS/ECU. The ECU is only concerned with the rev limit as far as ignition cut-off is applied.

Just some thoughts I've had about it.

By the way I will find out about the K5 limit but I'm still restricted under 10K rpm limit at 800 miles and climbing. I've routinely clicked off 150mph indicated quite easily without so much as any effort for the K5. As if it was just getting started for the elusive 200 mph barrier.
 

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Haskovec's SuperStock 1000 hit 198mph at Daytona. We run about stock gearing there.
 

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Well, with the old config with ran about 1-2 teeth taller than stock and would usually be about 1000-2000 rpms from redline before shutting off on the banking.

With the new config we actually ran 3-4 taller than stock to allow for 1st gear use on the new infield but we have alot more rpms left in 6th on the banking.

I haven't a clue if kit ECU's are legal in SuperStock.

Either way, I was able to his 181 with my 04 and I was far from being the 'fast' guy. I bet if I was able to carry the exit speed from the chicane a lot of the uber fast guys did, I'd have a higher trap speed.
 

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if you want to try to get a more acuret speed try what i did and go look at www.veypor.com for a nice little toy that has its own speed senser. it was shocking how far the speedo gets off as you get up there
 

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my personal results of diferent runs measured with GPS on 1k :

stock gearing&michelin pilot sport 190 without tre =294 kmh
with tre =298 kmh

metzeler sportec 190 without tre =297 kmh
with tre =301 kmh
17-41 & sportec 190 without tre =300 kmh
with tre =306 kmh
 

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my k3 went 177mph on gps stock, after a trip to lees and a tre it went 184mph with the same gearing---- my k5 went 177mph last sunday on gps, it is stock with about 400 miles on it.
 

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my personal results of diferent runs measured with GPS on 1k :

stock gearing&michelin pilot sport 190 without tre =294 kmh
with tre =298 kmh

metzeler sportec 190 without tre =297 kmh
with tre =301 kmh
17-41 & sportec 190 without tre =300 kmh
with tre =306 kmh
Interesting results. Seems almost too close to call what is actually happening. However, at high speeds, 1 mph/kph steps is much more of an effort, unless an abundant amount of power is available and drag coefficients is good at that speed.

Perhaps there is something in the 6th gear ignition advance compensation that affects speed. Which would seem to me to be a process of retarding the engines time to maximum power before or near the final drive limit. But if it is doing this it's not able to prevent a whole lot of speed or distance over time traveled, from your results.

We know that a vehicle is ultimately limited by the final drive ratio even if you have abundant power to go faster. You will eventually hit your rev limit if the gears aren't allowing more travel. It's a combination of the final drive ratio, engine power and aerodynamics. If you improve all of the above you can go faster. But it gets exponentially more difficult the faster you want to go.

If the factory is limiting speed electronically it seems to be an afterthought, as the bike nearly reaches the final drive ratio limit at maximum power anyway. I'm not sure what to think other than the stock conditions of the bike are not that limited.


Good stuff.
 
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