So if the stock speedo is optimistic but the stock odo is pretty much accurate then what happens when a speedo healer is connected, does it effect the odometer reading?

 

In one word, yes. You simply have to figure out how much it will be out (equal to percentage of correction if gearing is left stock; alternative gearing will muddy things a bit) and do some calculating to get an accurate number.....

The best way to check it (especially if you have changed the gearing, as noted above), IMO, is to use the road-side mileage indicators (sample it over a given distance, say 10 miles or 20 km, and extrapolate from there).....

 

sorry, so are you saying that the speedo will be healed but the odo will be reading the mileage at a faster rate (assuming I've geared the bike lower?) (ps I'm referring to the odo and not the trip, not sure if that makes a difference)

 

Odo and trip is the same, if one is of the other is of by the same amount... And yes, they are affected... The same signal is driving all three... Change that either way and the all change by that amount...

But trust me, the odo is never 100% accurate as stock either... Just figure out a point in the middle, where the speedo is accurate enough to not get you tickets and the odo is fairly accurate...

 

The odometer will be eading mileage at slower rate. For my bike when I ran stock the odometer was a bit fast but not as fast as the spedometer. When I went to 43t it was faster still. After "healing it" I decided to go as accurate as I could on the speedometer, and not worry about the odometer.
With my speedometer right on the money my odometer is about 5% "slow"