Quote:
Originally Posted by Ghetto2315
Not sure if anybody knows the answer to this but if you look at the diagrams above and you see the diameter for Size 1 and Size 2 and then % diameter difference.
If going to non-OEM tires like we all are discussing, do front and rear tire both have to be -% or -% (or +% and +%) or can front/rear can be -% and +%? The reason why I ask is because the % diameter difference plays a huge role in speedometer accuracy. If the front has a -% and the rear has a +% (or vice versa), does that cause an issue?
EDIT: For Example. If you go to a front 235/40/20, it is a -0.7% diameter difference than front OEM. So the speedometer will read slower than OEM. But if you put rear 255/40/20, it is a +1.1% diameter difference which means the speedometer will be faster than OEM.
|
Depends on there the speedo is driven from but I would expect a sensor on one of the rear uprights or from the ICE gearbox.
So the rear tyre is the important one. And going slightly larger is no bad thing as it will fix the flight speedo over read.