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Switching from triple to double?

garnettgarnett Posts: 196
edited November 2017 in Workshop
Hi there - hope somebody can help or point me in the right direction.

I have a 2005 Trek 1500 triple with Shimano (5500) 105 groupset.

It's been explained to me by 2 different bike shops that set-up is tricky because of the fact it's a triple. I know it's not impossible because it ran smoothly for the first 2 years or so, and one bike shop in particular was always able to replicate that smoothness.

However, for the sake of an easy life (and also because of the mockery I endure for riding a triple) I'd like to switch to a double.

What will I need to replace to accomplish this, and is it worth considering upgrading/updating the groupset at the same time?

Thanks a lot for any help.

Posts

  • oxomanoxoman Posts: 9,453
    I currently have a triple with 105 and have never had a problem with changing gear or setting it up. That said I will possibly consider replacing it with a double when it's totally worn out and not worth repairing, whatever I replaced it with would have to replicate the same top and bottom ratios so that I didn't suffer on hilly rides. For this info i would probably use the Sheldon Brown website to compare. http://www.sheldonbrown.com
    Triples are a bit harder to set up but a decent bike mechanic should be able to do it easily enough. As to the mockery ignore the Sanctimonious sods and hopefully you will pass them walking on a really steep hill that defeats then.
    Too many bikes according to Mrs O.
  • mercia_manmercia_man Posts: 1,396
    I would try another bike shop. Setting up a triple is slightly more difficult than a double but any competent home or professional mechanic can do it easily.

    Changing to a double will be expensive. You will need new levers, cables, front and probably rear mechs, chainset, bottom bracket and probably a new cassette and chain to get things running smoothly - effectively a whole new groupset apart from the brakes.

    Only you can decide whether it's worth the expense to avoid the mockery of ignorant people.
  • timothywtimothyw Posts: 2,482
    So the groupset is 12 years old? Presumably the chain and cassettes have been replaced on a fairly regular basis, how about the chainrings and other components?

    To be honest, the difficulty is that shifting at the front on a triple is quite dependent on the ramps and pins on the chainrings at the front being matched up nicely, and over the past twelve years there have been numerous tweaks and refinements to the shimano line up of chainrings which mean that it is probably now near impossible to get replacement chainrings that are a perfect match, although even with perfect chainrings it is still fiddly setting up a triple as compared to the ease of a double.

    I was running a 105 triple of similar vintage up until early this year. After a somewhat fortuitous warranty claim on another bike I was able to replace it with a new Tiagra 4700 groupset (double - triple is available!) with a 52-36 semi compact chainset. It's probably the best upgrade to a bike I ever made. I hadn't realised how annoying the front shifting was until I didn't have to put up with it anymore (and I barely used the granny ring anyway), although it's fair to say my triple group was pretty worn out.

    If you want to do it on the cheap, you will want to replace the chainset and front derailleur at an absolute minimum - and you'll need to be careful choosing a front derailleur as pull ratios have changed in the past couple of years. Then you just set it up so that the front shifts have the middle position on the shifter as the inner ring (meaning that at worst the cable goes slack if you shift again - this is better than the mechanism jamming if you set it up the other way).

    Anyway, I can highly recommend that you spring for a new Tiagra groupset. 105 is also excellent, but you might have problems if you don't have 11 speed compatible wheels (plus it becomes questionable whether you are throwing a bit too much money at an old and relatively cheap frame).

    I wouldn't do it just because people are taking the piss though. Plenty of modern bikes with compact chainsets and wide range cassettes have much easier gears.
  • oxomanoxoman Posts: 9,453
    Just used the website to put in both my geartrains and they work out the same.
    http://www.ritzelrechner.de
    Basically my 105 triple with 11/28 rear cassette works out the same as my 105 compact double with 11/32 rear cassette.
    Too many bikes according to Mrs O.
  • Check the shimano compatibility charts.

    My 2007/8 vintage 105 LHS shifter (5600?) was compatible with either triple or double chainsets - this allowed me to switch from a double to a triple and then back again to a double by changing only the front mech (necessary) and the chain (due to it being too short / too long by a couple of links - you might get away without doing this).

    Alternatively, download the shimano manuals and set up the triple as per the manufacturers instructions - should shift fine then.

    Good luck
  • N+1 time
  • gozzygozzy Posts: 640
    I'd get a new bike shop if the mechanics told me they found it tricky setting up a triple.
  • Bumo_bBumo_b Posts: 211
    Having changed between a triple and double crank set recently, the only purchased item was the crank set. The triple shifters work fine with the double crank set, although make sure to adjust the lower limit screw. Obviously the change up to the triple from a double would require a change in the shifters as you normally have 5 points in the shift for adjustment over 3 rings.
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