Hollowtech upgrade?

37monkey
37monkey Posts: 141
edited September 2009 in Workshop
I have the 09 defy 3 and was talking to somebody earlier about a slight flex/play in the crank when I push hard on the pedals (sprints/hills/ect).
I know there's nothing wrong with the bike as it has just been serviced yesterday (lbs) and this was one of the things I asked them to look at.
Anyway the person I was talking to suggested changing to hollowtech as the bearings are further apart so there's less of a lever on them.
I want to keep a triple on the front for now as I still have an awesome display of quad failure, so what parts/tools do I need to buy and how hard a job is it to do?

Comments

  • topdude
    topdude Posts: 1,557
    Well you are going to need :
    HT2 Triple chainset
    HT2 Bottom Bracket cups
    BB tool to remove your cartridge BB
    HT2 tool to install the cups
    Not difficult to do and somewhere around a hundred quid at a guess.
    However, is it worth doing :?
    If it was to replace worn out parts then yes.
    But just to eliminate a small amount of flex no.
    He is not the messiah, he is a very naughty boy !!
  • Thanks Topdude, interesting point about is it worth it? I was under the impression that if I'm putting energy into turning the pedals any energy that goes in other directions eg. side ways flex is wasted. But I suppose the question should be does the accumulative energy waste over the course of a ride (30-50 miles usually) justify the outlay of cash? and would I notice the difference?
  • you'll want to get the BB faced too, get your lbs to remove the old cranks, face the bb and chase out the threads for good measure. Then you only need to buy the BB tools for the HTII setup.

    The flex is more likely to be frame/wheel than cranks. Stand on the non drive side and put your foot on the top of the crank by the axle, gentle push the bike across, you'll see how much flex you've got...
  • John.T
    John.T Posts: 3,698
    You can never eliminate flex. Only cut it down. This is usually done by throwing disproportionate sums of money at it. Better to wait until you need to change, then upgrade. You would probably not notice much difference while riding unless you are very powerful.
  • gkerr4
    gkerr4 Posts: 3,408
    John.T wrote:
    You can never eliminate flex. Only cut it down. This is usually done by throwing disproportionate sums of money at it. Better to wait until you need to change, then upgrade. You would probably not notice much difference while riding unless you are very powerful.

    agreed - it's your frame that is flexing - not the BB itself.

    Hollowtech2 will make an improvement but not cure that flexing - only a damned expensive frame will cure the flexing!

    Oh also - I have never bothered getting the BB shell 'faced' - imo this is unnecessary and adds expense to the process - and I also think that the external BB concept is worth upgrading to - they are also really easy to fit and maintain.