how to adjust a new deraulier for shimano 14-34t rear cassette to shift to the first easiest largest

Discussion in 'Cycling Equipment' started by yoshiserry, May 3, 2014.

  1. yoshiserry

    yoshiserry New Member

    May 3, 2014
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    Hi guys,

    I'm having huge trouble getting the deraliuer to shift into the largest easiest gear closest to the frame because the top jockey wheel on the derailuer actually just doesn't get close to clearing it.

    the hanger and deraliuer are both straight, both replaced in the last few days.

    I bought a new deraluier and it wont shift to the first aka largest aka closest to the wheel / dropouts gear its about two inches too high. So it (the deraulier) knocks into the largest easiest cog. I've fiddled with the B screw already tightening it all the way in. But the deraulier jockey wheel keeps rubbing against the first gear cog on the cassette.

    The smallest aka High Limit screw is already correctly adjusted I believe and I just had the deraliuer and hanger replaced so they are straight. the only thing I can think of is adjust the b screw but it didn't get the deraluer to be able to shift to the largest cog when i ADJUSTED IT.

    As the picture below shows (the deraliuer is too high, not enough vertical distance between the hanger/dropouts and deraliuer jockey wheels. I know its not on the second largest gear, but when it is, the same thing described happens. it won;t shift to the largest because half the jockey wheel hits it.

    The gears are currently on (1/3 in front) and (2/7 in back) the largest cog easiest gear to ride in is 1, which I can't switch to.
    I have a 7-8 speed SHIMANO ACERA RD-M360-SGS for $30 AUS


  2. alfeng

    alfeng Well-Known Member

    Jul 23, 2005
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    FYI. As a final solution ...

    If you REPLACE the upper jockey wheel with a 10t pulley wheel will almost ensure that you would be able to use access the 34t Cog on your Cassette without the clearance problem(s) which you are experiencing.

    BUT, before you try doing THAT, it is possible that you simply need to remove a few links from your chain. Doing so will allow the rear derailleur's cage to pivot forward & thereby change the derailleur's geometry.

    Check or to get the particulars on determining the appropriate amount of chain that a bike should have ...

    • essentially, you want enough chain to wrap around whatever Big-Biggest Chainring-Cog combination you have and a long enough cage to take up the slack when you are in the Smallest-Smallest combination which you have on the particular bike.

  3. oldbobcat

    oldbobcat Well-Known Member

    Aug 31, 2003
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    This derailleur is made for a 34t cassette/freewheel, so simply getting the chain length correct will suffice.

    CAMPYBOB Well-Known Member

    Sep 12, 2005
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    What they said. You have too many chain links installed for your chainring/cassette combination.