Question for those who have used this method for rear wheel alignment.. How many marks on each side show after you were finished? I just did this and there is a difference of 1/2 way between two tall marks and that seems like a lot to me. Just wondering if I need to look for something else out of place that is causing the difference like the forks or something bent....
That seems excessive. It could be different for all of us but I'd expect to find it within the closest hash marks.
Key ingredient is not bending the string around the tire or anything else. Its just needs to rest next to the leading edge of the tire.
Id suggest rotating the rear tire trying a different spot. Confirm string is not dropped into a tread/grove.
Good luck!