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Discussion Starter #1
I am questionning the accuracy of the speedometer reading on my 2014 Brutale 675. From what I can see, it seems to read high by around 10%. This is just a subjective assessment based on travelling highways where the speed limit is 100km/h. Following traffic, my speed reads over 120km/h on the gauge...

Has anyone done any testing regarding speedo accuracy? I will verify shortly with a GPS to understand what the real situation is. I hope it does not read high by that much because this causes the odometer to also record high, meaning the bike is aging faster than actual.
 

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There is a youtube video from 2012 with an f3 showing 280km/h +, which I would say is probably 7-8% out, the b3 would be the same.
Oh, and don't worry, daylight saving will not fade your curtains.:)
 

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Almost all motorcycles regardless of brand have speedo's that read high. This is very normal.
 

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I agree with VaporMV, I know all my motorcycles read high. I noticed this afew times with the signs the highway patrol put out that show how fast your going, as well as being pulled over clocked at 80, my speedo was at 85 the whole time.
 

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Discussion Starter #6
Thanks guys. I appreciate the feedback. I knew most manufacturers air on the high side.... but I would say the MV is on the very high side based on my own experience with other brands. If they all do this, then I wonder what is the rationale for this, I mean what purpose is served by communicating erronous information to the driver?
 

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...

I am questionning the accuracy of the speedometer reading on my 2014 Brutale 675. From what I can see, it seems to read high by around 10%. This is just a subjective assessment based on travelling highways where the speed limit is 100km/h. Following traffic, my speed reads over 120km/h on the gauge...

Has anyone done any testing regarding speedo accuracy? I will verify shortly with a GPS to understand what the real situation is. I hope it does not read high by that much because this causes the odometer to also record high, meaning the bike is aging faster than actual.
I know that in some countries, by law, your speedometer must show a speed exact or above the speed your actually driving.

For your concern of the bike aging faster than actual, with this knowledge of your speedometer reading high 10%.
I would suggest you lower your speed by 10%, this would prevent your bike aging to fast...:stickpoke
 

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All manufactures speedos read high. It's a liability issue. The odometer however is suppose to show the correct amount.
My Subaru is around 8% high. Subaru was sued in the US for having inaccurate mileage readings. They plead guilty to mileages being out 5%. Even though I'm in Canada I received a letter explaining that they had extended my warranty from 100,000 to 105,000 kms. To bad for me, I already had over 125,000 on the clock at the time.
My F3 675 and my Ducati 900 SS FE are both about 7% out. My wife's old Monster 600 was at least 10% high. Her bike used the same speedometer, cable and gears as my 900 but her bike had a smaller front tire.
 

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Are you kidding ?

Good stuff. Another option would be to punch open 4 windows on the 48 tooth trigger wheel located on the rear disc brake. I will give it a try starting with two.
Are you sure this is what's used for the indicated speed, and how do you plan to confirm you have the right reading at all speed, with a GPS :stickpoke. That would be even more ridiculous.
 

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Discussion Starter #13
Are you sure this is what's used for the indicated speed, and how do you plan to confirm you have the right reading at all speed, with a GPS :stickpoke. That would be even more ridiculous.
Don't worry for me mate. I do this for a living. The only thing I fear is the speedo throwing an error code if there's an algorytm expecting evenly spaced pulses like on a crankshaft trigger wheel setup with a hall effect sensor where the trigger wheel pattern is X number of tooth minus one or two tooth which is now the standard on most modern engines.
 

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PSI, first off, welcome to this mad world.
I just spent a weekend tooling around on my S4Rs Monster with a Garmin Zumo 660 GPS on board. That speedo was about 10% optimistic for speed. IMHE, every speedo everywhere is off by about that much, say 8-10%.

What is it that you do for a living that would have you punching open additional speed sensor windows, yet you don't realize that this is not a condition unique to MV?
 

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Discussion Starter #15
PSI, first off, welcome to this mad world.
I just spent a weekend tooling around on my S4Rs Monster with a Garmin Zumo 660 GPS on board. That speedo was about 10% optimistic for speed. IMHE, every speedo everywhere is off by about that much, say 8-10%.

What is it that you do for a living that would have you punching open additional speed sensor windows, yet you don't realize that this is not a condition unique to MV?
Thanks for the warm welcome. Actually, I am a professional engine tuner and I am an authorized MoTeC dealer in Canada. My focus is mainly on building smaller turbocharged engines, 1 to 1.5 liter engines, developing up to 650hp at over 4 bar boost, mainly in drag drag racing snowmobile applications as well as race jetski applications. Drag snowmobiles are rigs that run 1000 feet in less than 6.5 seconds at over 160mph on asphalt or 660' in less than 5 seconds at over 130mph on snow. Can share a few youtube clips of what we do if that's of any interest.

Call it professional bias, but I just can't stand inaccurate calibrations. Maybe this speedo thing is not worth the trouble after all.... but it still bugs me....:laughing:
 

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It is possible that MV have built this into the program to stop you young hoons from getting yourself into trouble. That explains why the odometer is correct but the speed reads higher.

Don't waste time with this.

Spend your time wisely and put one of your one liter, 4 Bar turbo'd engines in your B.:f4:

Now that would a project.:stickpoke

ps. Don't let the Aussies stir you up too much.:)
 

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PSI...sounds like great fun!
 
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