Can you help me understand chainrings?

DannyOnTheRock
DannyOnTheRock Posts: 24
edited April 2017 in MTB buying advice
Okay so I bent a chainring and have decided that I want a narrow/wide single chainring on my bike to replace the current 3 chainrings I have there at the moment.

I'd like to get a race face ring and want it to be similar to the middle ring in that 3 ring setup I have but I'm so confused with what I need to get.

The ring there now is 130 with 32T - the lowest 130 ring has 44T but I could fit a 104 ring with 32T or more. Will having the same number of teeth produce the same gear ratio I'm after or is it the size of the ring that matters?

Comments

  • robertpb
    robertpb Posts: 1,866
    The pitch is always the same, if I'm understanding you correctly.
    Now where's that "Get Out of Crash Free Card"
  • DannyOnTheRock
    DannyOnTheRock Posts: 24
    So a 32T chainring will be the same diametre regardless of if it's 104 or 130 yes? What exactly is the 104 measurement as I thought that was the diameter from point to point.
  • robertpb
    robertpb Posts: 1,866
    It means that 44 teeth is the same no matter what bolt hole mounting you have, the distance across each link in the chain is the pitch.

    As to the size of the chainring it's got to have a range of gears that is suitable for the cassette and your riding.
    Now where's that "Get Out of Crash Free Card"
  • DannyOnTheRock
    DannyOnTheRock Posts: 24
    Right so a 32T chainring is perfect for me. I tried riding in the mountains yesterday just in that one gear on the front with no bother. So is the 104 measurement the size of the spider the chainring goes onto?
  • robertpb
    robertpb Posts: 1,866
    Yes it is.

    What cassette do you have on your bike, in the information you've given on this site your bike comes with a 14-28 that will only give 200% gearing not a lot for mountain biking, close to 400% would be normal.
    Now where's that "Get Out of Crash Free Card"
  • cooldad
    cooldad Posts: 32,599
    If you are right about the '130' it would be the bolt centre diameter, so a 104 will not fit your cranks.
    I don't do smileys.

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  • DannyOnTheRock
    DannyOnTheRock Posts: 24
    @robertpb

    I've no idea but my next project is to fit trigger shifters for the rear derailleur with a 10 speed cassette. I've just got to get the funds for it all and measure the freewheel to make sure it fits.

    @cooldad

    Yeah I got it wrong. It's a 104 i want not the 130. The 130 measurement came from the tip of one tooth to the tip of the opposite tooth on the ring. Now i know that's not right and it's definitely 104.

    Thanks for being patient with me guys. I won't be a noob forever lol

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