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I have a Liv Alight commuter bike that was sold with a single chainring 38T with combined cranks.

Its mated to a 7spd cassette 14T-34T.

Would i just be able to get a regular shimano alivio/tourney triple crankset, 3spd FD, front shifters and just get it to a triple? Would my chain need to be changed or should the stock 7spd Tourney be able to handle the extra tension/slack?

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    If the largest ring on your triple is more than 38 teeth you'd probably need to add more links to the chain. Probably might as well install a new chain. Feb 2 at 2:16
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    As well as what Daniel says, you need to make sure your rear derailleur has enough spare capacity to also take up the slack between the largest and smallest chain rings.
    – DavidW
    Feb 2 at 4:37
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Frames sold with 1x builds may be designed in a way that's freed of the constraints of FD bikes.

  • They might not have the small or large ring clearance needing for any given multi-ring crank.
  • The seat tube might not accommodate a front derailleur by virtue of its diameter, placement/angle/curviness, whether it's even tubular, etc. If it's round and in the normal place, but a nonstandard diameter that's less than 34.9mm, you can typically solve the problem by just beer can shimming up to 34.9 and using a 34.9mm FD. There are also some braze-on FD adapter mounts that have been made for odd diameter seat tubes, but that wouldn't help for non-road bikes.
  • There may be no accommodations for FD cable routing, although in most cases if you've got a seat tube that can take an FD anyway then you can solve this problem fine using a clamp-on housing stop and a top or dual pull FD, then run full housing to that stop and zip tie it to the top tube.

A pretty common scenario from having done this on a few different bikes is the first two aren't issues, but a clamp-on housing stop is needed on the seat tube. It makes sense from a manufacturer's standpoint to offer the cleaner look and not have unused housing stops, so that's what most of them are doing. I've also seen one 1x native bike I can recall with a seat tube diameter in the 33s.

Many bikes, especially hybrid/urban bikes, will do exactly what you propose without issue. You may need a new bottom bracket depending on the crank you pick out and whatever you have now. The chain will need to be replaced if it was sized properly to begin with and now you're going to a larger chainring. You'll also need to make sure your rear derailleur has the total capacity to handle the new gearing; bikes that come with 11-34 and an basic long cage MTB/hybrid derailleur will tend to have total capacity for a triple, but bikes that had wide-range cassettes to start with may not.

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    The rear derailleur may not have enough capacity to handle a chainring swap. If OP keeps the 14-34 and adds even a front double with a difference of 16, a derailleur with 30 tooth capacity is needed. A triple will be even worse. Feb 2 at 3:42
  • Nathan, the stock specs do show that it sold as a 3x setup and i can see signs that a FD was installed previously. it looks like a standard square taper bearing. there is even a housing for the FD cable on the downtube! my only concern is needing a new chain :( i don't have a chain breaker tool) i was wondering how i would even install a FD without breaking the chain, if the length was ok. Another question, are crankset teeth dependent on the RD? Would a 2x10 crankset work for my 7x cassette meant for 3x7?
    – Paul Pah
    Feb 2 at 3:43
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    You need to understand the term "total capacity" and then your questions about tooth counts will be answered when you look up the total capacity number for the RD you have. Some FD cages are joined by a screw, which can undone to pass a chain through, and others are riveted, so the chain has to be apart to install an FD. That is pretty immaterial because you will need a new chain in almost all cases. That it's square taper is only part of what's in question with the BB because square taper BBs come in different lengths. There are many questions here about figuring that out. Feb 2 at 4:31
  • @PaulPah: I’d just get a chain tool (and master link to close the chain again). At the very least you’ll need it the next time you have to replace the chain. I think some front derailleurs can be opened/split into two to allow installation without opening the chain.
    – Michael
    Feb 2 at 8:23
  • @NathanKnutson it seems that the max capacity is 43T for my RD. i'm looking at getting a triple or double chainring infront, in regards to chain/chain tension. won't the RD take up extra slack/tension as long as my capacity is within range with my new 2x or 3x crank?
    – Paul Pah
    Feb 3 at 0:42

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