Compact crank vs. triple

Discussion in 'Cycling Equipment' started by rdr0912, Jun 22, 2007.

  1. rdr0912

    rdr0912 New Member

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    Recently I bought a new Scott s-20. It has a double 105 crank. Some of the hills here are kinda steep. I've debated getting a triple crank so I can commute with this bike and I don't have to kill myself getting up some of them with a small bag at 530 in the morning.
    What is the difference between the compact and triple crank? Is the compact literally smaller in size or are the sizes of the chainrings closer together of what?
    Thanks in advance
     
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  2. sogood

    sogood New Member

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    You can calculate it. But I'd say that triple will give you an extra one to two gear steps lower down.

    http://sheldonbrown.com/gears/

    Unless you really need those low gears, how about just change the cassette? It would be much cheaper than changing the crankset. But just make sure the cassette size is appropriate for your RD size.
     
  3. Dancier

    Dancier New Member

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    This has been thrashed out before, you're going to open up another can of worms.

    Depends what your preferences are but i like triples because when you've got zero in the tank after a lonng ride and few hills before home, they become invaluable. A compact is just a poor substitute for fat old guys like me.[​IMG]
     
  4. thomas_cho

    thomas_cho New Member

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    There are also other considerations to going compact (double) or triple.

    Going triple would mean you have to get a shifter that can do triple (if you have the 105 shifters ,u already have it), a new FD, new RD, new Crankset, new chain.

    Chances are that you will get better at climbing hills the more you do it. So perhaps the compact is the least expensive route to go at this point.
     
  5. Camilo

    Camilo New Member

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    I really like my triple, but if you just bought a bike with a double, it is not a practical change to make. Financially, I think it is something that should be done on initial purchase, not retrofitting a new bike. There's just too much to change out, considering you'll be buying brand new parts and selling off used parts.

    Changing to a compact double involves far fewer expensive parts. If you do that and maximize the size of your rear sprocket, you might find you are where you need.
     
  6. rdr0912

    rdr0912 New Member

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    It's not that I want to change for fitness reasons...I am able to use the double that I have now fine. I feel like I have gotten quite a bit stronger than I was in early spring. My 'problem' or question is that I sometimes use this bike for commuting. There are some hills that I just don't want to climb with a small bag on and either at 530AM or after a long day of work. I am debating making the change but I wasn't sure how much I would have to give up on the top end when I go on training rides as opposed the the gains I would get when I commute.
    Someone said something about a new cassette. I have the 10 sp. 105 now. I didn't realize that there were different sizes for them. What kind of options do I have that way? What do you all think about changing that vs. the crank (and associated parts) and the gains and looses I would see?
    Thanks
     
  7. KellyT

    KellyT New Member

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    I have triple's and compacts, they are both a lot more useful in hilly terrain than a 53 39, which is just a torture device really. The compact is my own personal favourite though. It's a little lighter, not a critical amount, but excess weight never the less. It has less gear overlap, the triple has quite a few gears that are the same, crossing the different front rings, which is pretty pointless. But for me, most importantly, the compact just feels a little more intuitive to find the 'right' gears. Raking through the three front rings for the right gear just 'feels' more clumsy and time consuming than using the compact, which generally gives me the gear I need really quickly.

    I have changed a couple of 53 39's to compact and I would say the investment has been completely worth it. The Tiagra compact is excellent value too.
     
  8. gfspencer

    gfspencer New Member

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    I'm an old guy (60) and I just returned to the wonderful world of road bikes. When I got my new bike my LBS recommended a compact crank and I “bought” their arguments . . . mainly because I have grown tired of messing with the three-speed crank on my mountain bike. I have not been disappointed with their recommendation. I have rolling hills where I ride (a few are pretty steep) so I might change the cassette to get slightly lower gearing but so far the compact crank has worked out great for me.
     
  9. cPritch67

    cPritch67 New Member

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    Stick with the double, tough it out for a few weeks and you'll continue to get stronger. After a few weeks, you won't even notice the bag on your shoulder.
     
  10. Camilo

    Camilo New Member

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    Another option other than changing your crank to a compact (or triple): Put the smallest chain ring and the largest rear sprocket.you can (that your derailleurs will accomodate) . As you can see from the Shimano website referenced above, you can go to a 12-27 in the rear. Depending on what you have now, this could be a significant change. I'm not sure what you could change your front small chain ring to, but the shop that sold you the bike could advise. The whole package could make a significant difference for very little money, depending on what you have on there now.

    You would be losing very little on the "top end" (assuming you're meaning the "fast gears"). At most, you will be changing from an 11t rear sprocket to a 12, and leaving the front large chain ring the same - therefore very little change there.

    One more thing - a lot of times bike shops are willing to work with you to change these things on bikes they sold you - to minimize costs.
     
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