Bogie track drivers

[400brian]

Here is a heads up to all you guys running JD bogie sleds. As far as I know, all of the Kioritz powered bogie sleds ran white track drivers. From what I can tell, the 74 and 75 300s ran the black ones, then after that ran the white ones. The 72 and most of the 73 sleds ran a 1" drive axle. The 73 X8s were upgraded to 1 1/8" mid-run. From 74 on, they all had the 1 1/8" shaft.

You will also find white drivers of another pitch count on the Dator and 78 CC.

I have no idea why they switched to the black plastic drivers on the slide rail sleds, or why they used them on the 74 and 75 300.
But here is the deal: 15 or 20 years ago, Rainville was spinning a track on a Dator in his garage, when one of the drivers grenaded and then rolled up the bare leg of a buddy standing nearby ( and yes, it left a mark ). After that incident, Joe started telling guys to inspect the white drivers on their sleds.

Around 2011, I began a restoration of the 72 400 my father bought new. The drivers had around 2000 miles on them, but they looked like new. These white drivers were made of what appeared to be a nylon type material. They had a molded in aluminum hub, and stainless steel pins in the sprocket teeth. I would say they had excellent wear properties, and seemed pretty tough. I fully intended to put them back into the sled.
Joe urged me to inspect them closely, so I humored him. To my horror, when I held them up to the light, I could see large cracks starting at the hub and going almost to the outer edge!

When we compared notes, he told me he had dug out an NOS sprocket he had, and made the same discovery. So it appears use has nothing to do with the issue, and this has been supported by everyone else in our circle. Apparently the material has continued to out gas or shrink over the years, setting up stresses that tears them apart.

To anyone who is still running these, I would suggest you are running on borrowed time. Sooner or later these will fail. If all you do is putt around the farm or yard, I guess it is not such a big deal. But if you ride them like you stole them and put on some miles, perhaps you should be looking for some black drivers, AM52563.

Used is what we are left with for the most part. Some Scorpion guy
has re-popped some all plastic drivers, but they seem to be available on a once in a while basis. I found a set for my 72 restoration in the 1" bore that I needed, got lucky.

Maybe you guys are all aware of this, just thought I would put it out there if not.