Crankset upgrade & BB Compatibility

MattBlackLamb
MattBlackLamb Posts: 7
edited November 2014 in Workshop
I recently got knocked off which resulted in my left-hand crank getting bent, fortunately that was the only serious damage I or my bike sustained. As you can't get replacement single cranks I thought I'd get a bit of an upgrade on the FSA Velo 46/36 that I currently have.

The BB in my bike (Cannondale CAADX Sora) is a square taper FSA 7420, having not found many square taper cranksets it looks like I'm going to have to get a new BB too.

What I'm wondering is whether it's worth getting something that fits the BB30 standard that my bike has or if it's worth getting a BB that adapts to HollowTech standards & getting a Shimano crankset as shifters & derailleurs are Shimano? Does having all Shimano parts make things noticeably better or is it worth going for a BB that fits the standard machined into my bike?

Thanks for your time :)

Comments

  • simonj
    simonj Posts: 346
    Unless your adamant you want a HollowTech a BB30 bottom bracket would be simplest, an adapter adds an extra things to go wrong. You don't need matching crank, I tend to have FSA cranks on most my bikes with Shimano or SRAM kit.
  • MattBlackLamb
    MattBlackLamb Posts: 7
    I would rather have a BB that is going to last, reliability is more important to me than the name written on the components.

    Does it matter if the crankset is for a different size groupset? Lots seem to be for 10 or 11 speed, will it matter that I only have a 9 speed cassette?
  • simonj
    simonj Posts: 346
    BB30 lasts as long as others if done right, although it can sometimes require a bit of maintenance. If it gets noisy, mine have done from time to time due to dirt getting in, but all I needed to do was remove crank, clean surface of crank and BB30, regrease and reassemble. Shimano HollowTech bearings do not tend to need this and some prefer them due to this. Some bike manufacturers who have not made their BB30 frame with tolerances as they needed to be have had more serious problems, but I've had many Cannondales with BB30 and non of them have had real issues, just a bit of a clean out as described above once in a while. Not sure on the 9 with 10/11 cranks, I have used many 10 cranks on 11 speed bikes, but not 9 with 10.
  • MattBlackLamb
    MattBlackLamb Posts: 7
    Would a PF30 BB be a good alternative or is it worth sticking with BB30 as it's Cannondales own BB standard?

    I've been hunting around for 9 speed cranksets, both CRC and Evans have a very small selection and often no mention of which BB will be required.
  • simonj
    simonj Posts: 346
    No PF30 requires a slightly bigger hole as it's basically a BB30 in a plastic sleeve and PF30 and BB30 are basically the same apart from that. Other option is trying to find an FSA vero square taper and sticking with your BB?! In fact does your square taper BB have an adapter already to make it fit BB30? If so then you could use that same adapter to fit another BSA type BB and crank - like HollowTech.
  • MattBlackLamb
    MattBlackLamb Posts: 7
    I've been looking for other square taper BBs, have had some success but don't really want to spend a fairly large sum for just one crank...

    It might have an adapter in it, I don't have the tools to take it apart so haven't checked yet. Something to think about though.
  • simonj
    simonj Posts: 346
    If you're not overly fussed on which crank, wouldn't a replacement square taper crank be cheaper than a new BB30 crank - maybe not if a bit rare now days..
  • Monty Dog
    Monty Dog Posts: 20,614
    If you have a square taper BB, then you must have a threaded insert fitted? Search threads, but general opinion is BB30 is a pile of poo. There's a reason the likes of Shimano don't make BB30 cranks even though they'd profit nicely from replacement bearings. Get some regular external bearing cranks like HT2, GXP or MegaExo and ride-off creak-free.
    Make mine an Italian, with Campagnolo on the side..
  • MattBlackLamb
    MattBlackLamb Posts: 7
    There's not a lot in it from a price point of view for square taper / other crank types although there is the extra cost of getting a new BB.

    I've seen a few crank sets come with GXP BBs, are they designed to fit regular 24mm size BBs?
  • keezx
    keezx Posts: 1,322
    No, GXP is different.

    BTW a separate left crank with square taper is easily available....cheapist solution.
  • MattBlackLamb
    MattBlackLamb Posts: 7
    I've been looking for 172mm black left cranks but with not much luck :(

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