Thursday, October 30, 2014

This is Why I Can't Have Nice Derailleurs

Commute-ending chain suck. Scary. Cell phone pickup requested. Master link right there under the derailleur.

The final ride of the Biopace 48 chain ring set occurred on 10/30/2014. At approximately 7:50 am, under heavy pedaling force while being shifted with a dirty chain, it gave up the ghost. Born: 1989. Died: 2014, aged 25. RIP. 

Full and excellent chain suck study linkage: states that the chances of chain suck occuring with a new chain ring and new chain are nil. Done.

Biopace 48: it lives! Rise obsolete chain ring, rise from the dead! May you live 25 more!!



  1. I didn't know you could buy new Biopace chainrings...NOS?

    1. Tucson GABA bike swap bargain. I think they were $9 NOS. Not an incredibly popular product. I'm not a proponent of them, but I'm not an opponent either.

    2. My husband's MB 2 has Biopace chain rings. He says it's not a big deal and you easily get used to it. For you, NOS is a great find and a cheap replacement to get your bike running correctly. Last time I paid 25.00 (locally) for one chain ring!

      BTW, I couldn't wade through your link to chain suck. Too much information. My eyes glazed over.

    3. I think the (old) conventional wisdom that Biopace is pretty good for steady cadence and distance and easier on the knees has been true for me on my commute. I maintain a steady, medium pace, and my knees are not bothered.

  2. Replies
    1. Khal, I think I have narrowed down the problem to somewhere between the derailleur and the chain ring. More analysis may be necessary...

    2. Of course, rear derailleur lack of tension could contribute as well...

    3. After reassembly I will adjust the B screw and check, Steve.


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