Speedo inaccuracy with gearing change?

[Sean]

So I finally found a deal I couldn't pass on for a -1, +2 520 conversion. Now I'm wondering about how to accuratly gauge my actual speed. One friend said 15%, one said -10 mph and one said use the radars on some streets...and other ideas?

Does anybody use a Speedo Healer? Is it worth $100?

Thanks!

[Kitten]

I know someone that uses a speedo healer on his geared bike and it is right on.

[Zach929rr]

Yup. Depends on whether you like a correct readout or like knowing that you need to be at, say, 93mph indicated at a true speed of 85. I don't have one and am about to nab one up.

[Bueller]

uncorrected you will rack up miles that you didn't really do, is it worth $100 towards resale value

[bulldog]

Ralph (rforsthyn?) use to have a post a long time ago how to do this using mile markers on the road; maybe it is still on the boards. I think that is how I did mine back in the day with my old bike and it was right on. I also have heard about doing it using a GPS. Of course you need a Speed Healer, Yellow Box, etc to make the corrections.

[drago52]

I know from conversations with people who own my bike model that the speedohealer will correct speed, but then screw up your odometer. When you change your gearing, the odometer doesn't change, just the speedometer. The speedohealer changes both.

http://www.vfrdiscussion.com/forum/index.php?showtopic=50291&hl=speedohealer

[TFOGGuys]

I know from conversations with people who own my bike model that the speedohealer will correct speed, but then screw up your odometer. When you change your gearing, the odometer doesn't change, just the speedometer. The speedohealer changes both.

http://www.vfrdiscussion.com/forum/index.php?showtopic=50291&hl=speedohealer

It makes sense that the speedohealer should fix both the speedo and the odo, since they reference the same pickup. The issue would arise if the bike had significant speedometer error form the factory (as most do) without the corresponding odo error. Correcting the speedo at that point would make the odo read lower than normal.

[Boy Scout]

Now I'm wondering about how to accuratly gauge my actual speed. One friend said 15%, one said -10 mph and one said use the radars on some streets...and other ideas?

Does anybody use a Speedo Healer? Is it worth $100?

Thanks!
Speedo error tends to vary between bikes. My F4i was off about 5%, while my 600rr was off only about 2.5% (prior to correction).

How to accurately gauge your speed (in no particular order):
1) RADAR on street.
2) Handheld GPS unit
3) Cell phone if it has GPS/Mapping capability
4) Pick a speed and ride at that speed from mile marker X to mile marker X+1, while timing the time it takes. That can be difficult to do safely with accuracy as you would need to be fumbling with a stop watch.
5) Ride around town at 100 mph until you get pulled over, then ask the cop. j/k

I've had one on both of my bikes and love it. If it was strictly a race bike, it may not be worth it unless you absolutely must know how fast you are going, but you're not supposed to be looking anyway. :)

It is fairly common for the odo to be accurate from the factory, while the speedo has some percentage of error (sounds stupid since they use the same signal, but it's true). Because of this, you can make the odo accurate, the speedo accurate, or split the difference. I chose to make the speedo accurate.

If your odo is accurate and your speedo is fast, making the speedo accurate will cause the odo to read fewer miles than actual, which could increase the value of your bike (if you put on a bunch of miles).

[Sean]

Nice! Thanks for the tips!


5) Ride around town at 100 mph until you get pulled over, then ask the cop. j/kBut by the time they catch up, the cops are usually to pissed to give me an accurate response. Then after the pepper spray and taser gun, I sometimes forget to ask. :banghead:

[Ricky]

If someone tells you a specific mph, they are dead wrong. ANY change to the speedo, due to a gearing change, is going to be a percentage.

[Matrix]

I rode around a long time with the -1+2 change and because its a % change it took a little brain power to do it accuratly at different speeds. I felt a lot better about the correctness of the ticket once I got the speedo healer. :banghead:
One thing that I do think is cool is the new ones have a top speed recall button. I never used it on the street but for the track I would check it from time to time in the pits to see if I was improving my top speed (throttle on corner exit + strait + throttle off corner entry).

[Ricky]

I know from conversations with people who own my bike model that the speedohealer will correct speed, but then screw up your odometer. When you change your gearing, the odometer doesn't change, just the speedometer. The speedohealer changes both.

http://www.vfrdiscussion.com/forum/index.php?showtopic=50291&hl=speedohealer

That just doesn't make any sense to me. the speedo and odo are getting their figures off of the same piece of equipment that is tracking the speed of a specific sprocket. It's not like the speedo has a sensor in one place, and the odo uses a different sensor. I mean, it's possible for there to be two sensors, but why???

The calculation of speed is based on the distance a sensor has moved within a certain amount of time.

[*GSXR~SNAIL*]

Sean-

Same conversion I had on the GSX-R1000. Fun, but inaccurate.

As most others here have mentioned, it will throw it off quite a bit...racking up more miles than actual. Riding next to a buddy of mine on I-25, I was reading 98-101 mph, when he was reading 84-86. My bike was certainly off, not sure how right on his was though.

And we all know, that I wasn't doing the 176 mph that I read just prior to breaking on the Pueblo straight.

[brennahm]

From what I've HEARD, the 04-06 R1's speedometer was off by some 6-7%. Again, a speedo healer would correct the speedometer, but the odo would be off. Now (and this is for you Webman!) there is only one wire carrying the speed signal into the instrument cluster and hence this is the only place for the speedo healer to interfere. INSIDE the instrument panel, the factory intentionally makes the speedo slow and the odo correct. Why? Who knows...but still, if you're changing the one signal that's interpreted two different ways then...

We've had guys come in and have their speedo healer corrected on the dyno and get a printout to take to court to fight tickets. I think we only charge a half hour or so if you install the unit yourself.

[Bueller]

Speedo and odo are 2 different boards, fed by the same pickup. You can either get either the odo or the speedo right or split the difference.

[bodhizafa]

I have a GPS you could borrow for calibration. How good was the conversion deal?

[Sean]

Riding next to a buddy of mine on I-25, I was reading 98-101 mph, when he was reading 84-86.

And we all know, that I wasn't doing the 176 mph that I read just prior to breaking on the Pueblo straight.:shocked:I can't believe how different they were! It just helps confirm that I might want to calibrate it. :hump: And 176 mph seems a little high, but you are a wild man. So anything is possible?


I have a GPS you could borrow for calibration.Cool, thanks! It's a good thing you just bought that! :lol:

[Boy Scout]

We've had guys come in and have their speedo healer corrected on the dyno and get a printout to take to court to fight tickets. I think we only charge a half hour or so if you install the unit yourself.
No need to over-think this. The Speedo Healer has a signal generator built in and a correction calculator online. Note the odo, let it run for 5-10 minutes, then check the odo again. You can calculate the error and adjustment needed from that. The online calculator will also give you step-by-step configuration instructions.

[brennahm]

I'm not trying to say it's the only way to do it. Just another option.

[noskills]

I have a Healer and I like it but worth 100 bucks? :dunno: It's nice to know your speed and not have to constantly calculate or if you wish set it for Odo and keep the mileage on your bike accurate. If you have all your gear and have the cash lying around go for it.

[Spiderman]

Figure out what your actual speed is/will be, then you can decide if you want to invest in a speedo healer:

http://www.cosportbikeclub.org/misc/SpeedCalc.html

[CaneZach]

When I swapped out the stock for -1/+2, my speedo was reading 81 MPH while the "check your speed here" radar trailer said 65, or 81.25% off.

[Zach929rr]

I think you mean ~20% off....

[drago52]

That just doesn't make any sense to me. the speedo and odo are getting their figures off of the same piece of equipment that is tracking the speed of a specific sprocket. It's not like the speedo has a sensor in one place, and the odo uses a different sensor. I mean, it's possible for there to be two sensors, but why???

The calculation of speed is based on the distance a sensor has moved within a certain amount of time.

As previously mentioned, most bikes (I dare say ALL) come from the factory with the odometer exactly right and the speedometer off by 5-7%. If you get a speedohealer, it will fix the speedometer, but now your odometer will read less. I went -1 on the front for gearing and my speedo is 15% off. If I got a speedohealer and calibrated my speedometer, then my odometer would be 15% low. You can't calibrate them both.

I'm not sure why the manufacturers always put in "ambitious" speedometers. I ride the a GPS and when I hit 100mph on the speedo, the GPS reads 85mph.

[CaneZach]

I think you mean ~20% off....

You know what I meant:loop:

[Tipys]

I just go by what feels like it is the speed limit (or what I feel like going)