# AW Tjet Ultra G R12



## TK Solver (Mar 18, 2004)

I picked up six of these cars for $10.99 each during a recent AW inventory reduction sale. After my usual prep work, all six cars ran great right out of the box. But then two of them started slowing down after about two minutes of track time. Nothing was binding. It was a heat issue, because if I let them cool down for awhile, they'd run great again for a couple minutes. I tried adjusting the brush spring tension and the problem didn't go away. I ended up swapping the brushes with those from some older AW chassis and the problem went away. I haven't seen this issue with the other four R12 cars.

Any thoughts on this? Did AW change brush materials? Why doesn't the problem show up on all the R12 cars? Could it be some interaction with the "lubricants" AW puts on their chassis? I did inspect the brushes and "polished" them on a sheet of paper but it didn't help.


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## slotcardan (Jun 9, 2012)

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## Rich Dumas (Sep 3, 2008)

Possibly you do have a slight binding issue, that is very common with JL/AW cars. The problem is that the cluster gear shaft on these cars is a little short and does not always fit into the hole in the base chassis. When that happens the whole assembly will get tilted and the mesh between the crown and drive pinion as well as between the idler and driven gears will be compromised. The fix is simple enough, first push the upper end of the cluster gear shaft so it is flush with or maybe just a little lower than the top pf the driven gear. Next push up the drive pinion a little, but not so far that the assembly is too tight. The shaft has splines, make sure that they do not ride in the gear plate hole.


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