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  1. #1
    WNC Native
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    Smaller Chainring on 2011 20" Hotrock??

    Has anyone put a smaller chainring on a 20" Hotrock? I have one of the green 2011 versions. My daughter loves it and has been doing well with it, however I think going from the 36T ring to say a 32T ring would probably help her some on the climbs. She will be on it for the rest of this summer and possibly some of next. So I don't want to crazy on rebuilding it or sinking money into it, however if the chainring swap can be done I'm all in.

    From browsing other threads I've gathered that the chainring may be riveted to the crankarms and need to be drilled out, I can handle that. Also saw it's probably 110 BCD.

    Anyone do this to their kid's bike?
    "I ride to clear my head, my head is clearer when I'm riding SS. Therefore, I choose to ride SS."~ Fullrange Drew

  2. #2
    mtbr member
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    Not familiar with this exact crank, but all the pictures for 20" hotrock I find look like they have a steel chainring swaged directly to the crank, no intermediate spider that the crank can be removed from. Rivited cranks are usually only found on cheap cranks with >1 chainring, in which case the middle and inner chainring are typically rivited to the non-removeable outer ring. Best bet would probably be to replace the entire stock crank with a small sinz or bulletproof brank BMX crank (square taper, 110mm BCD 5-bolt). Added benefit is that you can get these cranks shorter than 140mm which is probably a bit long for most 20" bikes.

    Downside is that a 4 tooth difference in chainring is only equivalent to changing 1 tooth on the freewheel. If you really want to gear it down lower, get another freesheel with larger low range cog (else switch to a casette hub an use a lower gear range casette).

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