XRAY - Model racing cars

Hi all...

After i attached the front and rear arms, i note that even the instructions said that it is extremely important that the arms move freely on pivot pins. They didn't at first, but after i pushed the holders out while i tightened em up, they seemed to do, except very very slightly they didn't move absolutely freely under their own weight. I don't have an arm reamer so i pushed on with the build, and figured i'd buy an arm reamer one day soon and re-try to get the arms to move freely under their own weight.

So, i got to now attaching the anti-roll bars., and note again that the instructions said to verify that both sides move at the same time. Well, mine dont. I've tried to tighten the screws only enough to remove excessive free play and still allow the anti-roll bar to move freely.

Does this all tie back to the arm's not moving freely? Should i go back to that step and ream the arms until they fall freely, and then continue the build?

Or is there some other things i can check with the anti-roll bars and the fact that both sides dont move at the same time?

Any help appreciated, thanks...

Let's just make sure that "MOVE AT THE SAME TIME" is being interpreted correctly. If you start to raise RH arm then the LH arm will not move immediately; you have to raise the RH arm so far before the LH arm moves. Now when you change sides and start to raise the LH arm you should find that the RH starts to move when you have raised the LH arm the same distance that you moved the RH arm to make the LH arm move- hope that makes sense!

All I can say is that that is how it has worked on all my XRAYs over the years - ie I have never moved an arm and had the other arm move immediately, "at the same time"

Oh, and, if you do not have a reamer then you can use a drill bit, of the appropriate size,to clean through the suspension arm and free it

It might be related to the arms.
It's a good idea to get a reamer anyway as if there is any damp etc at all come into contact with the arms they can swell very slightly and bind again.

For the roll bars, I would attach them to the mounts but don't connect the ends of the bars to the ball joints that are attached to the wishbones.
This way when you tighten the small grub screws on the mounts you can easily check if they are making the roll bars bind at all (the bars should easily fall under their own weight).

Also check the roll bars are flat by laying it on a dead flat surface, a sheet of glass or similar to make sure that one end doesn't stick up at all. If it does, try bending it a bit until it's dead flat.

Skiddins

Just built a T4 and found that the forward 2 pc al arm mounts can be loosened and re-tightened so the h pins to set correctly. Before you ream the arm I would run a hinge pin through it to see if it binds at all. If not then the binding is front to rear distance and not hole diameter related.

The "lift" of the rollbars is adjusted by the length of the actual anti-roll bar rods which mounts onto the arms. If the arms are not perfectly free, it may influence this action, causing them to bind up.