This particular frame probably has more miles than all the others out there combined (not by me mind you), so I would expect it to show problem areas first as well.
This thread basically documents the innards of the main pivot as a reference for other owners.
The Milk Money has its main pivot concentric to the bottom bracket to allow for single speed with suspension and no tensioning device.
The pivot is a plastic bushing type popular now a days on Turners and Banshees. It needs to be greased periodically via a zerk fitting on the underside of the bottom bracket.
You will know when it needs grease because it will creak incessantly until it gets it.
I have noticed that the time between greasing for me has been shortening and that when greasing, it seems the grease is not coming out of each side evenly, so I dismantled it to get a good cleaning and inspection.
Basically, the system is two plastic bushings pressed into the frame. Running inside of these as an axle is a hollow cylinder that the BB threads in to. The frame's pinch bolts grab the ends of the BB cylinder and it pivots inside the bushing.
Removal is pretty straight forward.
1. Remove cranks.
2. Back off one external BB cup (if that is your system, an internal BB could probably just stay there).
3. Loosen 5mm pinch bolts on the swing arm.
4. Whack with a rubber mallet to get it started out, the remove the loose BB cup completely.
5. Turn the other BB cup with the attached BB pulling gently and it will work its way out.
Here is the Axle with attached BB cup almost out of the pivot.
The BB axle is 73mm.
This is a look inside the pivot bushings and you can see the zerk at the bottom.
This is the swing arm with the axle almost out.
You can see some wear on the axle. The threads inside the bushing were shallower in a couple places corresponding, I assume to those wear points on the axle. Not enough grease there.
If one needed to replace the bushings, I imagine the process would be similar to the one nicely demonstrated here on a Turner.
My pivot was dryer than I would like and there was a bit of wear on the axle and the pivot. No slop in it at all.
Not sure why, but I suspect I have been greasing it with too heavy a grease (it was random wheel bearing grease I had laying around). Turner recommends Prep M which I think is a fairly light grease (please correct me if I'm wrong). I might need to pick up some of that for this frame. Also, I think next time I grease it, I will loosen the pinch bolts, and put a BB wrench on the cup and spin the BB axle around a few times to better distribute the grease. I usually cycle the suspension, but that is only a few degrees at most of movement.
I had some lighter "white" grease laying around, so I slathered that in there and reassembled. No problem getting it together. There is about 3mm of extra axle width which you can use to mess with chain line slightly. I just opted to center it.
I suppose you could fairly easily replace the BB axle and the bushings with new ones, but I saw no need here. It came together with no slop, and no creaking.
We'll see how long it lasts.
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