Mag swingarm measurement, please.

Hi y'all. If you have a real Mag swingarm, can I please have the measurement across the inner shock mounting plates?? Mine is a 70's custom shop copy, and need to rework the lower mounts to fit my Ohlins. But if a real Mag is wide that's an option, too, if one can be both found and afforded! Here's mine, about 7-13/16" or 198.4375mm for you smart people. Thanks!

From the picture posted it looks like you have a ProFab swingarm. A rare and rather desirable item in itself. I have seen them go for $250 +




It does look though that it has been modified at some point for 'laydown' shocks. Since you will be modifying the shock mounts anyway, consider using a 'regular' swingarm (inexpensive and plentiful) and modifying to exactly the configuration you want.

BTW - what is needing to be reworked for the Ohlins lower shock mount? Is it the width, diameter, or...? There may be an easier solution than fabrication and welding.

Yes I figured it a ProFab. The Ohlins fit the mounts fine, but their springs are larger diameter so they hit the chain. Just want to move bottom of shocks farther out. Revised stock arm is fine, but curious about the mag.

Wish I could answer your question directly, but I don’t have a Mag swing arm. I will stand corrected if wrong, but I do not think the width between the shock mounts would be much different than the ProFab or OEM swingarms due to the fact that they are both used on the MK frame. The thinking is that the top and bottom of the shocks need to be in line for them to work most efficiently.

Recently on this forum there has been good discussion on the proper way to rebuild and install forks. The outcome to note is to insure the fork legs are in line and centered by tightening the damper bolts only after the forks are compressed. In addition, tightening the axle only after compressing the forks a few times or measuring at a few points along the forks to ensure they are parallel.

The same thought applies to shocks in that the top and bottom shock mounting points should be in the same plane and parallel. In the modification that you are considering, the top mount would need to be moved outboard the same distance as the lower mount. If not, the binding of the shock rod, especially at full compression, would be hard on the seals and shafts.

Thanks Vinskord. Yes, the stock shock alignment straight up and down. And, I agree that the Mag and other stock arms are likely the same width... I was being hopeful for an easy fix! Fortunately, with the use of heim joints for proper articulation, the shocks can be angle quite a bit. They came that way right from the factory on the later years.

Refernce MJ/MK



XN



My setup will have to be a little more like the XN.