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Does any know if there is a Top speed limiter on the 1050 Sprint?
I done and indicated 173.4mph today and it felt like there was a definite stop once it got there, it felt like the limiter on Japanese car's, like a cut in the ignition or fuel for a second then it would go again.
I done it on a closed runway in case anyone is wondering
 

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Unless you have done some serious mods, the top speed is 160mph under perfect conditions. There is no top speed limiter, only rpm limiter at which point it will cut off till it gets below red line.
 

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Just an exhaust and a k&n filter. That's what it's indicating anyway, it's probably 160mph true speed. It's definitely hitting some sort of limit or cut, maybe it is the rev limiter but doesn't feel like it,
 

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And I was behind a hayabusa that said he was showing 180, wasn't a whole lot between us at the end of the run
 

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Just looked at video's on YouTube judging by where the rpm needle is on some top speed runs I may of been the rev limiter alright
 

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Does any know if there is a Top speed limiter on the 1050 Sprint?
Only the rev-limiter. Mine ran an indicated 177mph before it hit the limiter. On the dyno of course officer!



Mine has a top speed limiter. It is a pair of sensors located atop the seat, right where it meets the tank.
I had to think about that one for a moment. :)
 

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Discussion Starter #8
Mine has a top speed limiter. It is a pair of sensors located atop the seat, right where it meets the tank. It also activates considerably sooner than what your indicator shows.

That must have been a pretty steep downhill..
No it was level ground I'll have to get a video done for proof
 

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No top speed limiter.
Sprint won’t do 174 with stock motor. That’s speedometer error.
I’d be surprised if it pulled redline in top gear, but if it did you hit the rev limiter.
 

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Just an exhaust and a k&n filter. That's what it's indicating anyway, it's probably 160mph true speed. It's definitely hitting some sort of limit or cut, maybe it is the rev limiter but doesn't feel like it,
Have you had the fuel injection remapped? If not, that could be another factor. Running my Sprint on the dyno revealed over-rich fueling at the top end. Manufacturers often do that to provide additional protection for the engine. With the over-rich fueling I doubt if my Sprint would have pulled more than 9,000 rpm in top gear - although I never tried until after the remap.

Prior to the dyno work I was already running the correct map for the TOR exhaust. Even though it was the correct tune for that setup it was still too rich at the top end and too lean in mid-range for my bike. The mid-range was annoying and the reason I decided to buy some dyno time for a custom tune.

Despite what I said above, if you're getting 173 mph out of a 1050 Sprint then you don't have anything to complain about. With the 6% error programmed into the speedo settings, that equates to a real 163 mph. Of course that assumes the ECU parameters are correct. The ECU calculates the speed from the output shaft so if someone changed the gearing without adjusting in the ECU, then the reading will be wrong.
 

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Or more off if the gearing was lowered which is what most people do.
If it’s lowered then the bike may have actually hit the rev limiter. That makes sense.
 

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I'm curious. Have you double checked your accuracy using a GPS device? Top speed I ever saw on my 1050 was an indicated 162. GPS said it was 149. Still bloody fast

Sent from my SM-G950U using Tapatalk
 

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....that assumes the ECU parameters are correct. The ECU calculates the speed from the output shaft so if someone changed the gearing without adjusting in the ECU, then the reading will be wrong.
Some numbers for those who may be interested:

With stock 19/42 gearing the 1050 Sprint would show around 170 mph at 10,000 rpm in top gear – if you can get there. Numbers can vary a few mph either way because the rev counter isn’t 100% accurate. We know that the speedo isn’t 100% accurate; it comes from the factory with approx. 6% over-read programmed into the ECU. If we compensate for that then our indicated 170 mph becomes 160 mph road speed. Tire variations could affect that road speed.

As Cburt mentioned, lowering the gearing is a popular mod. Adding one tooth to the rear sprocket would reduce our potential top speed to 156 mph road speed. If the speed-factor programmed into the ECU is not adjusted, then the speedo will still give the same 170 mph reading at 10,000 rpm in top. The same applies for other gearing numbers.

The photo showing 177 mph on my Sprint was achieved with the red line rpm increased. That was done as a temporary step to avoid the rev limiter interfering with top end tuning.

As a side note: anyone who considers adjusting their speedo to give a “true” reading should be aware that it will also affect the trip computer. That’s fairly accurate to begin with so adjusting out the 6% factory error will throw out the odometer, trip mileage and fuel consumption.
 

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Discussion Starter #15
I must check the gearing and do a GPS run.
I've done it twice, 174 the first time and 173.4 the second time
 

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Maddi, I'd suggest you check both the front and the rear sprocket sizes. FWIW, I fitted a 18T front on my 2006. Absolutely loved it after that.

Stock size for your bike should be: Front - 19T, Rear - 42T
 
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