niznai

I have just got one of these and I found that the bottom shock silicone O-ring is a very tight fit on the shock shaft. It is so tight, it is difficult to clip the holder on the body shock. Being a used car, I am not sure this is the original kit O-ring, so my question is if anyone knows what O-ring goes in there. The one on my car is exactly like the Tamiya red silicone O-ring.