Hello Jilles
Thankyou very much for starting this thread. I don't have any setup questions since I have found that car setup is something you have to work out yourself since everybody drives their cars very differently.
I do have some specific questions about the TRF416 chassis, however, that you may have some suggestions about:
1. I think most people have found that when we build the 416 we have to add quite a few shims to the direct center shaft before putting the flanged bearings on and fitting it into the bulkheads. For example I have to add four or five 4x0.2 mm shims to the center shaft. How much do you guys have to add, and do you keep it equal on each side of the shaft or do you add more to one side?
2. In the rear diff the diff balls are partially exposed, and running outdoors on asphalt the diff attracts a lot of dirt and hence requires frequent rebuilds. I currently use a small sheet of clear vinyl as a diff cover, but since it only sticks to the outside of the diff pulley they don't last long and more often than not come off. The same is true of the Tamiya diff covers: there just is not enough area for the covers to stick to and last more than a few runs. Do you have any tips on how to somehow protect the diff and keep it clean?
3. Obviously parts wear out as time goes by, but I have to constantly replace the swring shaft protectors (or C-clips) that you put on the rear swing shafts before putting then into the diff halves. For me they wear out completely after about three full race meets (I run 10.5), and although they are not an expensive part I seem to be constantly buying new ones. The other issue with this is that as soon as they wear down a bit the swing shaft starts damaging the diff halves. Do you have any tips on how to make the C-clips and diff halves last longer? It seems that the Xray C-clips last significantly longer, would trying another manufacturer's C-clips help? What would be really good is if Tamiya went back to the design of the original TRF415 and TRF415MS, where you didn't have C-clips on the rear swing shafts just a ring the clipped to the end of the diff halves. If you got the delrin diff halves for the 415 and 415MS they seemed to last for a long time.
Sorry for the long questions! Thanks.