8 - The Swing Arm

 I took the swing arm into work with me today and had a look at it on the surface table. With just a couple of measurements it seemed things were even more complicated.
 Although there was a 4.5mm difference in the heights of the shock mounting bolts, there was only a difference of 2mm across the height of the axle. 

 So the swing arm did have a twist but it didn't amount to the difference noticed at the mounting bolts. The only explanation could be that these bolts must have been welded into the lugs of the swing arm at different heights. It seems a bit odd because you would expect them all to be built in a jig. 

 After a lot of debating in the workshop about the best way to correct the problem we had to leave aside our "engineering heads" and think to ourselves "we're not going racing on this wee bike, in fact we'll probably not be doing any more trials on it, so if we could correct the 2mm across the axle we would leave it at that.

 It wasn't hard to do, I just clamped the pivoting end in a vice, placed a long bar between the two legs of the swing arm and gave it a push. Now the axle's level and the height difference of the shock mounts is approx 2.5mm. As someone remarked, the only time I'll ever notice it is when I'm taking the shocks on or off, and that won't be often.

 Still I'd like to know from anyone if they have come across a similar issue with their bike.