Are they all the same width between the arms? I have a degenhart and a la forge and they seem the same. Only reason i ask is I looked at a front weight, (allegedly ex Fastrac) and it seemed a fair bit narrower. The ones i have measure 84cm between the arms and this one appeared to be only 76cm with short pins out the side I couldn't see how mine would fit. Always assumed they were the same. Anybody else noticed similar?