Odometer Inaccuracy

[Texas Blonde]

Hi guys ... used the search options for this one, but didn't come up with much. My odometer/trip seems to be losing @ 5 miles for every 100 I am riding. I have the stock tires and have made no sprocket changes. The bike is lowered with bones 2", but that is the only change I have made. What could cause this inaccuracy? Could it also be affecting the speedo reading? Does it really matter, other than it will show fewer than actual miles (which could work out in my favor later)? Thoughts?

[md86]

Best I can say is find one of those mobile radar things on the side of the road to check your speedo . Dunno WHAT could be up with your odo other than maybe a bad cable or gears in there somewhere .

[BucKatana]

Sounds like the perfect setup if you ask me. I'd just leave well enough alone.


It's a very common occurance from what I've seen.



buc

[SweetLou]

The speedo is usually about 5% to 10% percent off with all bikes. So say you are going 65mph, you may be only going 60mph (thats how my bike is now...) Something that can cure that is something like a speedo healer or yellow box. This will fix the speedo issues as well as your milage.

[The CyberPoet]

Re: Odometer Inaccuracy

My odometer/trip seems to be losing @ 5 miles for every 100 I am riding.

Standard deviation.

Your bike take's it speed readings from the transmission output shaft (the front chain sprocket, effectively). Anything that varies the distance on the ground compared to the "idealized" set-up will alter the bike's speed and distance calculations, including:
(you already covered this Sprocket changes
as well as
Tire wear
Tire brand (not all 150/70ZR17's are identical in actual size)
Tire growth (all tires increase in size during their first week or so of use, anywhere from about 2% to about 8% for typical street tires, up to about 24% for track tires).

Plus there is a legal requirement for the manufacturer of the bike to have the speedo over-report the speed, so that they can't be blamed (legally) for you getting a speeding ticket inadvertently.

My thoughts:
If you are still riding on the Macadams (the "stock" tires), sell them ASAP (eBay) and get yourself a set of Metzeler Z6's or Pirelli Diablo Stradas. The difference in grip/handling is much more important than the 5% inaccuracy you might currently have -- and may save your life at some point.

SweetLou listed two of the four possible fixes (yellow box, or speedohealer). The other two are printing new covers for your gauges that are calibrated to your actual speed, or changing tire brands to something that will get closer to zero percent.

Cheers
=-= The CyberPoet

[Texas Blonde]

I have been considering the tire change, so it looks like I just had the little push I needed. I will start there and see what happens. I know it's a good thing, as long as nothing else is getting screwed up. On the next service I'll have the cable checked just to see. I'll let you know what type of difference it makes with the odometer. Thanks for your replies.

[chriskatana]

IOn the next service I'll have the cable checked just to see. I'll let you know what type of difference it makes with the odometer.

FYI, there is no Speedo cable on your bike, it is driven by and electronic signal that reads the rotaion of the front sprocket.

[md86]

Oh yeah , I guess it's just us with the old tech machines that could have a problem like that . Don't listen to me , I'm we todd did .

[The CyberPoet]

On the next service I'll have the cable checked just to see. I'll let you know what type of difference it makes with the odometer. Thanks for your replies.

As chriskatana pointed out, there is no "cable" driven speedo in your Kat (98+ Kats are driven electronically with a pulse sensor at the speedo and a hall-sensor type magnetic pick-up at the tranny end). Thus, either your bike is getting a signal or it's not, and if it wasn't, your speedo would be dead.

Don't listen to me , I'm we todd did .

Huh?

Cheers
=-= The CyberPoet

[chriskatana]

Don't listen to me , I'm we todd did .

Huh?

Cheers
=-= The CyberPoet

I'm "we-taw-did"

[Texas Blonde]

[Texas Blonde]

Getting new tires this weekend. My husband favors the Metzeler because he has always ridden on them, but has no firsthand experience with the Pirelli's. What should be considered when choosing between the two?

[SweetLou]

Between the Metzlers Z6's and the Perilli Diablo Stradas (there new tire), they are supposed to be pretty close in performance and everything, but I found that the Perilli's were a tad bit cheaper in price at Americanmototire.com

[crazyaussie]

Don't listen to me , I'm we todd did .

Huh?

Cheers
=-= The CyberPoet

I'm "we-taw-did"

You both have it wrong. The real saying is: "I'M SOFA KING WE TAUGHT IT!"

[SweetLou]

WoW.

This thread got really off track