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Discussion Starter · #1 ·
I ordered one of these compact Centaurs in silver from a dealer who shall remain nameless for now. One of the junctions of ring/spider/bolt is very screwed up: there is a gap of at least 2mm between the ring and the spider (other junctions are flush); the bolt protrudes and will not thread down flush; the back of the threaded collar into which the bolt threads doesn't lay as flush as all the others; that same collar is machined so it fits into the hole and doesn't hit the spider (but does anyway).

I heard that there were some recent rings--don't recall which--that were not perfectly symmetrical (one hole is off slightly). Did the dealer cobble some mismatching items together, or WHAT??

Thanks in advance...
 

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Check and see if it's just sloppy assembly. What you describe sounds exactly like someone tightened all crank bolts on a canted chainring.

Remove all the bolts and the rings. Lightly coat all spider-to-rings contact surfaces and bolt threads with grease. Put the rings where they need to be (might take a bit of pushing and jiggling) and loosely insert crank bolts. Don't tighten any of the crank bolts until you're sure the rings are flush with the spider.
 

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Bent spider?

Although your description is kind of fuzzy for me, it sounds like you have a bent spider. Remove the chainrings and put the crank on a flat surface - you will easily see if the spider arms are all in the same plane. If the spider is badly bent, I would return the crank. If it is only slightly bent (maybe 2mm), then you can straighten it as follows:

Place the bike on its side with the crank supported on a block of wood at the axle. With another block of wood or a stout dowel placed at the end of the offending spider(s) give it a whack with a hammer. Check for change in alignment. If you got no change, hit it harder next time. Repeat until all the spiders are even. You may need to bend them away from the frame (brace the right crank on the block of wood) or toward the frame (brace the left crank).
 
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