Speedometer Error/Correction

ZED wrote:

inspector wrote:

Good information. So it sounds like if I correct for speed, almost no mater what the odometer is at least going to be closer then it was....

My thoughts too. What do I care if my ODO is out to lunch as long as I know where my speed is at without getting a brain cramp.

I figure that if I do my maintenance when it's needed, or within 10% of spec milage it's all good.
As for resale, I don't care if the milage reads higher than it actually is. If a potential buyer wouldn't buy my bike due to 10% higher milage then they wouldn't buy one of my bikes at all since I plan on miling them all out anyway. My plan is that like my KLR and my Ducati, I'll have some worn out parts left over from this little thing when I'm done with it.

Now I just need to get off the fence and actually buy the corrector so I can rest my brain while riding.

actually, in almost all cases, once the unit is installed, if you are going to have an odometer discrepancy, it will end up reading a bit lower than it should, this of course starts happening only after the increment rate of the odometer makes up for any over incremented miles it occurred during the period of time the device was not installed.

12oclocker wrote:

actually, in almost all cases, once the unit is installed, if you are going to have an odometer discrepancy, it will end up reading a bit lower than it should, this of course starts happening only after the increment rate of the odometer makes up for any over incremented miles it occurred during the period of time the device was not installed.

Hi Brooks, I ordered one of your units. But I am surprised by your ODO quote here. It implies there is memory on miles traveled, and at what calibration (stock or modified), and then the bike (or your software?) compenstates until a true mileage is indicated. Really? Is this true? I have a hard time understanding and/or believeing that ... can you exaplin more please.

The reason I am asing is this ... when I changed the gearing my WR250R and also changed tires ... the Speedo/ODO was way off. I bought a speedohealer and tried true in the speed but then realied that the ODO was still off and that with the speedohealer you could only true one of those metrics at a time. So I took it off and sold it. Now SheWolf turns me on to your little gizmo and I say what the heck, I will buy it to at least true my ODO. I need my ODO to be accurate for Dual Sport and Turkey Run events that use a route sheet for navigation.

So, understanding more here is important to me. Would apprecaite it if you could explain a little more. Thanks, Ross

Gargoyle wrote:

12oclocker wrote:

actually, in almost all cases, once the unit is installed, if you are going to have an odometer discrepancy, it will end up reading a bit lower than it should, this of course starts happening only after the increment rate of the odometer makes up for any over incremented miles it occurred during the period of time the device was not installed.

Hi Brooks, I ordered one of your units. But I am surprised by your ODO quote here. It implies there is memory on miles traveled, and at what calibration (stock or modified), and then the bike (or your software?) compenstates until a true mileage is indicated. Really? Is this true? I have a hard time understanding and/or believeing that ... can you exaplin more please.

NO. He's just saying if you did the math in your head. More of a resale thing then anything else. (i swear it makes sense to me).

Gargoyle wrote:

The reason I am asing is this ... when I changed the gearing my WR250R and also changed tires ... the Speedo/ODO was way off. I bought a speedohealer and tried true in the speed but then realied that the ODO was still off and that with the speedohealer you could only true one of those metrics at a time. So I took it off and sold it. Now SheWolf turns me on to your little gizmo and I say what the heck, I will buy it to at least true my ODO. I need my ODO to be accurate for Dual Sport and Turkey Run events that use a route sheet for navigation.

So, understanding more here is important to me. Would apprecaite it if you could explain a little more. Thanks, Ross

In your case it sounds like if you set the ODO to be spot on for your events....then the speedo should be a lot closer to actual also.

*If any of this turns out to be incorrect (don't see how it could be) plz delete this post and replace with "idiot response deleted"

Here is a detailed explanation from my 12oclockLabs website...
the last paragraph gives an example of what I was talking about.

Quote :

it will correct the odometer as well,
although sometimes getting them both 100% correct continuously is not
possible,
this is because some bikes have an odometer error rate which is not
equal to the speedometer error rate,
since your ECU uses the same signal to determine both the odometer
reading and the speed reading,
this type of problem lies within the ECU itself. If you find yourself
in this situation,
you will be able to get your speed 100% and the odometer very close. Or
you can choose to get the odometer 100% and the speed very close,
or you could even choose a happy medium between the two, and get them
both equally close, its up to you, and it depends on how
far apart the two error rates are from each other.


To determine your Distance error rate, use this formula:
100 - ((Actual Miles Traveled / Miles Displayed on Odometer) * 100) = Distance Error Ratio
where "Actual Miles Traveled" is a mileage reference which is known to
be accurate, such as by a rolling wheel ruler, or laser distance
measuring tool.
(even wheel rulers and laser measuring tools have a margin of error)


To determine your Speedometer error rate, use this formula:
100 - ((GPS Speed / Speedometer Readout) * 100) = Speed Error Ratio


To determine the correction ratio for an error rate, you simply invert the sign, example:
for a 7% error rate, you would need a -7% correction ratio entered into your SpeedoDRD device


Another factor to consider is that your odometer has probably been racking up inflated miles for quite some time now,
so if your odometer is say around 4% errored and your speedometer is around 6% errored,
and you already have say 1000 miles on your bike, you really only have 960 miles on your bike,
and if you correct for the speed using a -6% correction ratio to get 100% accurate speed readings,
you will cause a -2% correction on the odometer. This means that 2000 miles after using your -6% correction ratio,
your odometer will finally read what it actually should.
This is the most common situation among users which have error rates which are not equal,
because the speed almost always has a higher error rate than the odometer if the two error rates are not equal.
For this reason, and in most circumstances,
it is usually best to go ahead and select to calibrate your speed to be 100% accurate.

OK, thanks for the replies. I will just try to get the ODO spot on.

no prob,
I've current got 4 SpeedoDRD Speedometer Calibrator units in stock ready to ship!

Is it a plug and play unit (no wiring to be done)?

AK

Akoffroader wrote:

Is it a plug and play unit (no wiring to be done)?

AK

Yep, plug and play.

SpeedoDRD healer
Just installed my DRD healer from 12 Oclock labs, nice unit. Once I figured the set up technique "no problem"
With a 606 (120/90) rear tire, and 13/46 gearing I used a -8.4%
calculation (ODO difference) and went for a trip around the block. At
45 indicated, my GPS read 42 and the ODO was a little slow (gps would
register a tenth just prior to my ODO). I am going to try a -8.3% and
see how close I get. With all my mods, I would really like to know what
my MPG really is. Kind of nice to have something accurate or closer
than before. Best guess, at hiway speeds I should only be off by 5 mph
as opposed to the 10 prior to the spd healer. (its a psychological
thing)
Given the variance between the speedo and odometer, I wonder
if the differences are closer on the "X" models !!! Are Japanese
calculators and watches this inaccurate ????

**UPDATE** with 73.4 (gps) and 73.1 (odo) I should come in at less than
.5 mile variation for every 100 miles traveled. The speedo is reading 4
mph fast compared to my gps at 70 mph. This was setting my DRD unit
-8.4%. This seems to be a nice compromise set up. I would imagine no 2
bikes would read the same with the same components, but pleased with
the results. Even if my gps is off slightly, still good numbers. This
is 2 days of work commute.

I wonder if trail riding with wheel spin in the dirt has any effect ?

I like geniuses that tinker with toys.


__________________

I got one of these from 12oclocklabs.com, too.
I was amazed at how tiny it was when I took it out of the shipping box.
These speedo recalibrators sure have gotten smaller over the years because the one I bought for my 2003 Yamaha FZ-1 was about the size of a typical cell phone. :)

Setting it up for my 12/45 sprockets was easy with the supplied instructions as the theory behind it was similar to ones I've used in the past.
Speedo is now reading something realistic.
Very satisfied with this unit.

I finished up my article on the SeedoDRD here - http://www.wrrdualsport.com/reviews-intro/bikeparts/97-speedodrd

I just love this little thing

oldirt wrote:

SpeedoDRD healer
I used a -8.4%
calculation (ODO difference) and went for a trip around the block. At
45 indicated, my GPS read 42 and the ODO was a little slow (gps would
register a tenth just prior to my ODO). I am going to try a -8.3% and
see how close I get.
...
Given the variance between the speedo and odometer, I wonder
if the differences are closer on the "X" models !!! Are Japanese
calculators and watches this inaccurate ????
...

Wow! 8.4 to 8.3, you're fine tuning by .1%
I'd be happy if I was within 10%
My WRX with 13/46 is currently about 30% out according to local radar signs.

I'm definitely planning on ordering a unit as soon as I'm back from my next trip.

I just installed a speedo healer which I purchased directly from Brooks at 12oclocklabs and I must say that this is a great device...very accurate and easy to install.
I'm in Melbourne Australia and I received it via USPS within the week from the US.
The unit is tiny and installs easily under the seat. The installation instructions are easily read and if you can change the time on a digital clock radio then you will have no problems doing this.

Installed my drd right after I got my x. Great product at a great price. I've just dealt with speedo error in all my cars and bikes in the past. Kinda cool being able to get it almost perfect. My stock x needed 7.7% correction when using gps. I entered that as I'm not concerned if the odo is slightly off. I'll like this unit even more when I go to change the gearing and tire size. I'd be interested in one for my Buell when/if they become available, hint, hint!

I can do a unit for your Buell no problem, if you can email me some pics of your speed sensor connector, I will track it down for you,
I did a plug and play unit for a 2009 Ducati Monster a couple weeks ago. I'll be stocking the plug and play Ducati units very soon.
thanks for the feedback guys!

I finally ordered mine. Definitely looking forward to it!

I look forward to when you've got the Ducati one ready.

ZED wrote:

I finally ordered mine. Definitely looking forward to it!

I look forward to when you've got the Ducati one ready.

If you can send me some pics of your Ducati speed sensor connector,
I may have the right connectors here already, if not I'll track them down and get some ordered!

I will do that next time I have the plastics off.

How much are these speedo/odo correctors?

Here you go:

http://www.12oclocklabs.com/

I believe he was offering a discount to forum members some time back. You might send an email to check on that, I think his email address is on the website.

Sarah

Mine is 5 mph high compared to my Garmin GPS.

Got mine the other day. I just need time to install it. Gteat service, fast shipping.

I ordered a SpeedCali to calibrate my speedometer. It was super easy to install and calibrate and it was less expensive than all other calibrators out there. Check it out at SpeedCali speedometer corrector

I want to order three, for myself and two friends. Which model is preferred?

12oclock labs or SpeedCali?

Are there others to consider?

Will either correct both speedo and odo?

Just for reference.. gearing is 13/47 and 14/47.