Viewing 11 posts - 1 through 11 (of 11 total)
  • 9/10 speed road compatibility
  • Spin
    Free Member

    My dad has a compact 2×9 set up on his road bike. 50/34 at the front and something like 11-30 at the back. He wants lower gearing and the most straightforward way seems to be a new chainset. I’ve found a 10 speed gravel double with 46/30. Will this work with his 9 speed chain and current shifter? I think everything else is Sora. Open to other suggestions too, I’ve got a bit out of the loop on this stuff!

    bikerevivesheffield
    Full Member

    What is the chainset? The chain and rings will work for sure

    bikerevivesheffield
    Full Member

    Why not an 11-34 or 11-36 cassette?

    Spin
    Free Member

    Why not an 11-34 or 11-36 cassette

    I was thinking that would require a new mech.

    Spin
    Free Member

    What is the chainset?

    Shimano GRX FC-RX600 GRX chainset 46 / 30T, double, 10-speed, 2 piece design – Black

    Although I’m now wondering if there would be issues with using the existing front mech on a much smaller chainset.

    steezysix
    Free Member

    Older Shimano 9 speed MTB and road rear derailleurs have the same pull ratio, so you can replace the Sora one and get a bigger cassette. The front derailleur will probably work ok with smaller chainrings, but might not shift as smoothly.

    I had the same Sora setup on my road bike, switched to a 42t single N/W chainring and 11-36t cassette. Lost a bit of top end speed but I’m not a super fast rider anyway!

    Spin
    Free Member

    Older Shimano 9 speed MTB and road rear derailleurs have the same pull ratio, so you can replace the Sora one and get a bigger cassette

    Cheers, I think I was coming round to this idea!

    poolman
    Free Member

    I m lowering the gearing on a touring 3×9 setup, with a medium cage derailleur spa cycles reckon I can go to 24 34 44, based on that’s the tooth difference on existing setup.  If it doesn’t change as smoothly as existing i m not that bothered as don’t expect to be using the granny ring that much.

    hofnar
    Free Member

    Although I’m now wondering if there would be issues with using the existing front mech on a much smaller chainset.

    That could be a real issue with a 46 or smaller chainring it depends on how low the front derailleur can drop on the frame. If its clamp on or a clamp on support you are most likely in the clear. If the support is fixed to the frame often it doesn’t go low enough.

    timba
    Free Member

    GRX sticks out 2.5mm further to clear wider hubs and fatter tyres. The road front mech might not be able to deal with that and engage the big chainring

    mrauer
    Full Member

    nevermind

Viewing 11 posts - 1 through 11 (of 11 total)

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