I am having problems aligning my rear wheels to run on the axle heads. They are canted 2.5 degrees using the rr tool. During alignment test the rear wheels drift toward the body when rolled foward, and drift toward the axle head when rolled backwards. I thought that this indicated a toe-in problem and rotated the axles in the slots to correct. It appears that no mater how I adjusted the toe-in and toe-out by rotating the axles, the wheels continually drift towards the body when rolled foward and toward the axle heads when rolled backward. Any advice? (I am using the pre-existing axle slot)
You are correct that you want zero toe or a slight "toe-out" on your rear axles where the wheel migrates toward the axle head when the car is moving forward.
Here are a couple of suggestions....
You should turn your rear axles so that the wheels migrate out during forward movement. Consequently, if you are looking at the back of the car, make the following adjustments to tune your axle rotation - start with your axle head facing up at 12:00 o'clock - the left axle should be turned slightly clockwise - the right axle should be turned slightly counter clockwise - if you are still having problems, drill another hole for your dominant wheel axle so that the front end of the car will be lifted.
If you are still having problems, send me a PM and I will call your tomorrow night to help you resolve your issue. Murph Shining Light Tribology
I should have mentioned that my FDW is the only wheel touching the track.
This is our third year canting our axles and have always had success adjusting the toe-in, toe-out by rotating the axle heads as you discribe.
Is it possible that my rear axles are not canted after using the rr tool? I am reasoning that since my son did most of the axle polishing himself this year he may have taken off more of the materiel than in past years hence decreasing the diameter of the polished portion of the axles. Could this have created less of a cant when using the rr tool? In my (limited) experience, I could always oberve the negative camber of the rear wheels when holding up the cars with mounted wheels and axles. This year, I cannot observe a difference.
But, I am not sure this would account for the accessive tow-in I experience in the alignment test. I do not believe that it is possible for the pre-existing axle slot with straight nail heads to produce two toed-in wheels in the rear? Maybe on one side, but not both.
It does sound like the axles are slightly undersize, BUT no problem here.
Cut a 1/8" strip off the end of a standard business card, remove the axles and put them back in the Pro Rail Rider Tool and wrap this strip around the axle shaft at the head and repeat the process. This will give you the additional offset you need.
Another tip is that with a strip off a biz card, you can have even more flexability in you Pro Rail Rider tool. You will have 1.5deg & 2.0 deg (with strip) and 2.5 deg amd 3.0 deg (with strip)
Also watch your slots, we see a lot of them that are not square to the centerline of the body, while it is best to have them correct, you can adjust for some slight imperfections.
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