Mounting 104 BCD to FSA or Race Face Spider - Help

vman

Active member
Jan 1, 2023
68
42
Marin County USA
Trying to mount up a 104 BCD chainring to a new spider for a Bosch Gen 4. I have the park chain ring tool, but its very awkward to try and use a torque wrench while trying to hold the back of the chainring with the crappy chainring tool and also trying to hold onto the chainring so it will not lodge itself into your workbench or your arm. On traditional bikes I would simply mount the chainring to the crank and use the crank arm to stabilize things while I torqued them down....that does not work in this case as the spider does not mount to the crank. Any ideas ? Thanks

V
 

vman

Active member
Jan 1, 2023
68
42
Marin County USA
For those that might have a similar issue - I figured out that the key is to go very slowly and work your way up to the big TQ when you use the bigger TQ wrench. I used a small T wrench to get all the bolts as tight as I could by hand, then used a small TQ wrench to get them to 6 NM, then brought them up to 10 NM using my bigger torque wrench in one hand while stabilizing the chainring against a piece of cardboard it could sink into on top of a bench. I Used a leather work glove to hold onto the chainring while working it with the TQ wrench and the crappy chainring spline tool in the other hand. I know understand why Wolf tooth charges $25 for chainring bolts that have a 4 mm instead of spline on the nut side, not sure why all the manufactures have not ditched the spline nut except maybe cost.
 

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