• 05-25-2019
    solitone
    Rear derailleur for Megarange freewheel
    My son's bike has a Shimano Mega Range 14-34T freewheel, it's the Shimano Tourney MF-TZ31. It's a 7-speed freewheel, with 14-16-18-20-22-24-34T cogs.

    I'm thinking of upgrading the stock rear derailleur, a Shimano Tourney RD-TY300-SGS:
    https://bike.shimano.com/en-EU/produ...TY300-SGS.html

    It doesn't work consistently well with the low (34T) cog. The low regulation screw has to be almost removed. Still alignment under the low cog is not perfect. So I need to increase cable tension, but then shifting to the high cogs is worse.

    Furthermore, I'd rather have a short cage (GS) derailleur, being the bike small.

    The shifter is a Shimano Revoshift SL-RS36-6R:
    https://bike.shimano.com/en-EU/produ...L-RS36-6R.html

    What would you suggest?
  • 05-25-2019
    Kingfisher2011
    TX55. My son's Felt came stock with a TX55, it's a short cage and works with the 7spd megarange. No troubles shifting into the big gear out back. I also upgraded to SL-M310 shifters, dirt cheap and gets the kiddo used to triggers.
  • 05-25-2019
    solitone
    Thanks for the reply, I'll consider that. It seems to be long cage though, the product code is RD-TX55-SGS, and AFAIK SGS means long cage.
  • 05-25-2019
    Kingfisher2011
    Nope you're right. SGS is long, GS is medium. For some reason I was thinking it wasn't a long cage, I'll own that. It is indeed a long cage. :(