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Has anyone noticed their speedometer being off? I've noticed that occasionally traffic around me doesn't seem to be flowing at the rate my meter says. For example, this morning coming to work traffic was moving at what my speedo says was 87-90mph. At 90 my tach said approximately 5300 rpm. Is that about right? My gearing is stock as far as I know (I'm the second owner). About what rpm is say, 55 and 70 mph for you guys?
 

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Stock gearing on your bike is 19T front 43T rear. On my RS in Second Gear (still stock) 2000 rpm is 20mph 3000 rpm is 30 mph and so on. Also since the speedo sensor is in the front gearing will not change this. Yes your speedo is wrong. I have checked mine with GPS and the bike speedo is about 7% to high. How ever the oddometer is dead on. Bike manufatures do this on purpose. I have been on group rides with a hole varity of bike all are speedos read diffrent at the same speed but every bodys oddometer read the same after a given distance. The only bike that showed true speed was an Aprilla.

“When the dogs are looking for their bones and it’s raining ice picks on your steel shores”
 

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I too have GPS varified and mine is about 10% high. When I am doing 60mph on the GPS, the speedo on the bike says 66mph. Odom is dead on though. Remeber too that some tires have taller profiles, and as they wear that too may alter the speedo. I'll have to check what my RPM's are this evening.
 

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3Banger, please explain "Also since the speedo sensor is in the front gearing will not change this". Does this mean if you change your sprockets, it will not effect the speedo readings? Or is that not the same as gearing?

Umm....bye.
 

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3Banger, I'm bored so I'll chime in.


The RS has its speedo feed off the front wheel (I think the right side). You can follow a black wire down the forks to the hub. That is your speedo feed. Some bikes, for sure the Honda f4, feeds off the front sprocket. It counts revs of the sprocket than does some math to give you speed. If you alter the gearing on that type of bike, the computer is counting revs, but your bike is going a different distance per revolution of the wheel.
 

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Changing your gearing IE sprockets will only effect your rpms meaning if your bike was reading 5000rpm at 90mph and you went up a few teeth on the rear or down 1 tooth on the front. Your tachometer would read about 5500rpm at 90mph which gives your quicker acceleration but less top speed. I have heard of people hooking up bicycle electronic speedos to there motorcycles and getting a more accurate reading, more like 1% error since you measure the circumfrence of the tire and enter that into the speedometer. They also tell the time, average speed, top speed, current speed and have a stop watch all for under $50.00.

 

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Yes, I mean the speedo sendor is on the front tire on the RS. Changing the sprocket ratios will not effect it. Diffirent tires and tire wear will make a diffrence, but it is still a pretty small precentage.

“When the dogs are looking for their bones and it’s raining ice picks on your steel shores”
 

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Awesome news. That was the only thing keeping me from changing my rear sprocket. Would you shy away from chaning the front to 1 tooth smaller? I've heard that this can put stress on something.

Umm....bye.
 

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Stock is 19t which is a big sprocket. I went down to 18t in the front and kept the back 43t. If I did it over again, I would have gone 44t in the back. But I took so much chain out to move the axle in as far as possible that I would have to add links.

You will be fine with an 18 tooth in the front.
 

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I plan on dropping one tooth up front and going up two in the back. WildRS had 17t front and 45t rear and didn't seem to have any problems.

“When the dogs are looking for their bones and it’s raining ice picks on your steel shores”
 

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Well you got six gears to pick from from so you can always pick a good gear for cruiser. In sixth down the interstate you will be at a little higher RPM. But even at 80 or 90 sixth is pretty low RPM on a stock geared bike.

“When the dogs are looking for their bones and it’s raining ice picks on your steel shores”
 
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I checked my SpeedTriple w/ my GPS and found at 60-100mph, it was reading about 5mph faster than I was going.
Mine has the mechanical cable driven speedo unlike the 02s.
Apparently there is a little known DOT regulation which specifies a speedo CANNOT indicate lower than actual speed and the Mfgrs mostly make sure this won't happen by miscallibrating them. My former kawasaki and a bud's ducati do the exact same thing 'cept the duc reads almost 10mph too high.

 

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As far as gearing, I'm currently using 18/45. My bike, being an '01 had a 19t front and I swapped that down to 18 right away. I went to a 45 rear two weeks ago and I just love it! Gas mileage?? Don't care! Bike still feels comfortable cruising at 70 but man what an improvement in the twisties. Love the power but does make throttle transitions much more sensitive when cornering. Seems to fit my use and style well. Will have to do an RPM check next time out.

Nugget'01 Sprint RS

Just because I'm paranoid doesn't mean they're not watching me!
 

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Bearing in mind that although location data from a GPS reciever has some error, that error may also be potentially amplified when measuring velocity vectors. In other words.....GPS accuracy can vary as much as your speedo and is not the most accurate way of calculating actual speed.

Rules are made to be broken.
 

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Way to go nugget with the 18/45 combo! Unless you spend alot of time over 150mph, it's a great combo, with the stock sprockets, first gear is so friggin long, the 18/45 is perfect. I even played with a 17/47 combo on the 02 Daytona, kills the top end but the acceleration is insane, probably a good combo for track days though.
I think a two bros pipe and the 18/45 combo is enough to make any 955 rider more than happy!
 

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My 2000 955I had a 18 front and a 42 rear stock I went to a 44 on the rear then this year I went to a 45 on the rear. I have an aluminum rear sprocket with only about 1000 miles on it and it still looks new if anyone is interested let me know. I have heard that it's harder on the countershaft bearings if you go to a smaller sprocket.

 

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Where are you guys getting your sprockets and such. I am about due for a new chain and am going to change the to 18/45 from 19/43 stock set up.

“When the dogs are looking for their bones and it’s raining ice picks on your steel shores”
 

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I got mine from Sprocket Specialist. The stock countershaft sprocket has a chunk of rubber attached to it, to do what I'm not sure. The SS didn't and I have not noticed any vibration or side effects.
 
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