Here's a brief history of my problem: After a few years of owning the UUC Evo III bank account drainer (err, short shift kit) I noticed my shifter felt sloppy. I pulled the boot off the shifter and noticed the carrier cup bolts (6x 3mm allen bolts) were not tight. I tightened them up best I could in limited space with a tiny allen key - ie not very much. It got better, til recently when I noticed 4 out of the 6 bolts were missing entirely, assuming they fell out over winter.
So I remove the shift carrier, here's what I found: The bolt heads sheered off. These are grade 8 bolts, and thought there's no possible way they were over-torqued with a 2mm cheapo allen key.



Anyways, here's why it happened. The bolt heads only have one flush surface to make contact with as you can see here:

and if you look here, you'll see EXACTLY why the bolt heads sheered off. When you torque down one side of the allens, it puts a good bit of force on the opposite side of the cup in the shifter. With all 6 bolts are torqued, add in vibration and forces from shifting, over time this is bound to happen.


This is an inherent design flaw - the bolts were not overtorqued at install, and this is NOT the first time I've heard of bolts backing out or breaking off entirely. Quite frankly for $350, this SSK should have come with a modified or new carrier.
My plan now is to drill and tap new holes around the carrier with flush surfaces for the bolts to meet. I will take pictures once I'm done.
So I remove the shift carrier, here's what I found: The bolt heads sheered off. These are grade 8 bolts, and thought there's no possible way they were over-torqued with a 2mm cheapo allen key.



Anyways, here's why it happened. The bolt heads only have one flush surface to make contact with as you can see here:

and if you look here, you'll see EXACTLY why the bolt heads sheered off. When you torque down one side of the allens, it puts a good bit of force on the opposite side of the cup in the shifter. With all 6 bolts are torqued, add in vibration and forces from shifting, over time this is bound to happen.


This is an inherent design flaw - the bolts were not overtorqued at install, and this is NOT the first time I've heard of bolts backing out or breaking off entirely. Quite frankly for $350, this SSK should have come with a modified or new carrier.
My plan now is to drill and tap new holes around the carrier with flush surfaces for the bolts to meet. I will take pictures once I'm done.




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