Speedo Off - New Sprocket The Culprit...

So, I'm riding around after installing a larger rear sprocket and I'm thinking the speedo seems way off. Am I correct in assuming the speedo gets it's info from the rotations of the front sprocket instead of the front wheel like most bikes?

Is there any way to adjust this?

yes you are correct, it is picked up from the sprocket. Fortunately there is also a simple fix for this. 12 o clock labs makes a speedo calibrator that just plugs into your wiring harness. i do not have one yet but hope to soon others have had good luck with them

12 o'clock labs speedo healer was my 1st mod. I originally got it to correct the factory's inaccurate speedo/od. It's best benifit has been being able to recalibrate your speedo/odo when you change tire and/or sprocket sizes. It's plugs into the existing wiring.

Best thing I ever did to my bike - http://www.wrrdualsport.com/reviews-intro/bikeparts/97-speedodrd

Just installed this device, but the device looks completely different from what Krabill's link shows, and the connector was further back than where the link showed as well (even though there is another connector like it above the negative post of the battery). I hope I installed it correctly, but the instructions clearly state that it will flash red and green if it's plugged in correctly, which it did. We'll see, I haven't tried it against the GPS yet...

Ok, so I had it plugged into the wrong plug!

No wonder it didn't change the speed... :)

Now I plugged it into the correct plug (the one directly above the negative battery terminal) and it works great. It's right on with the GPS now...

hamish54 wrote:

12 o'clock labs speedo healer was my 1st mod. I originally got it to correct the factory's inaccurate speedo/od. It's best benifit has been being able to recalibrate your speedo/odo when you change tire and/or sprocket sizes. It's plugs into the existing wiring.

Does this product also correct the odometer? I have a 13 /48 sprocket setup and the speedo is about 10 mph off and the odmoeter is incorrect also. Thanks for any replies

Yes, it seems to correct everything. I took a 70 mile trip on the bike and the GPS showed 69.7 miles and the odometer showed 70.2, so quite close (before the odo showed a much higher number than the GPS...)

GusinCA wrote:

Yes, it seems to correct everything. I took a 70 mile trip on the bike and the GPS showed 69.7 miles and the odometer showed 70.2, so quite close (before the odo showed a much higher number than the GPS...)

Thanks, Looks like a I'll have a late addition to the Christmas list!!!