Technical Question - Bullseye Cranks

Smithjss70

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Hello! I have an extra non-drive side Bullseye crank arm that has either been re-threaded incorrectly or possibly a factory faux pas. The issue is that the non-drive side crank arm is designed to slope away from the chain stay when installed in the correct orientation. However, the pedal lug's threads on this arm are tapped to accept the pedal from the wrong side, which if installed in that manner, will not clear the stay. I hope this makes sense. Essentially, the threads are backwards.

I surmise the following:

1) someone installed backwards, forced the pedal, rethreading it unintentionally with force
2) someone rethreaded intentionally but had the wrong orientation
3) factory blunder

Either way, I want to correct it and am seeking input on whether this can be easily accomplished. The threads are clean and allow for easy pedal installation but from the wrong side, so I'm leaning towards scenario 2 or 3 being the case. I've rethreaded aluminum cranks which is no problem but the hardness of the Bullseye steel gives me pause. My taps are hardened steel and of high quality (Park), but again, I've only used them on aluminum cranks. Thoughts or insights would be greatly appreciated before I attempt it.

Cheers!

Jason
 
This extra. Are you going to use it? I have been looking for a non drive side Bullseye for quite some time...
 
Thanks ishaw! It would have been but the pedals are new M737s so I wasn't keen on trying to find a NOS set and cannibalizing to right pedals so I took it to a machine shop today for a professional to correct with pro tools. He said it should be no problem no fingers crossed.
 
ErikFive":2msadd04 said:
This extra. Are you going to use it? I have been looking for a non drive side Bullseye for quite some time...

Erik

Ferry van der Stelt has a set for sale on FB. Very reasonably priced too in case you can't locate a single NDS arm. Good guy too. I've done a deal or two with him.
 
Just an FYI, crank arm was successfully retapped and is sporting a new M737.

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