such a simple but why oh why crank refit issue

andyh01
andyh01 Posts: 599
edited October 2013 in Workshop
Hi all I' ve had to take the.crankset off to change the bottom bracket, which I've done but for the life of me I cannot get the cranks back on, I've got the drive side on and some of the shaft pretrudes out the other end but by the looks of its short by about a couple cm on the drive side. I've tried tapping in with hammer but don't want whack it in anymore in case I've got something wrong and damaging it. I can get the left hand side, non drive side on and it will clamp with the screws but I can't get the bb retainer nut on that goes through the middle hole of crank on the non drive side, I'm also struggling to get the safety pin back in, I unscrewed the screws too far when taking it off so the whole thing came off, I think the hook has snapped off but I've been lining it up so the arms are in the right position on both side, but as drive side hasn't gone all the way through anyway at this stage the alignment isn't the issue. Should there be any gap between the external baring cups and the drive side crank or should the crank fit right up to the cups? I also notice there's a couple washers that sit inberween the crank on the inner chainring and the external baring cups, which on mine appear deformed in shape is this a spacer as it was about 2cm width but part of it has shered off, which is why I'm not sure if there should be a gap between bb and crank. Its an shimono r565 similar to tiagra thanks for any help

Comments

  • napoleond
    napoleond Posts: 5,992
    Pics would help. As would paragraphs ;)
    Insta: ATEnduranceCoaching
    ABCC Cycling Coach
  • stephenroberts
    stephenroberts Posts: 2
    edited October 2013
    Do you have the shaft fitted the right way round?

    I believe there should normally be more length on the non-drive side.

    Edit: "I've got the drive side on and some of the shaft pretrudes out the other end but by the looks of its short by about a couple cm on the drive side."

    Now I'm confused lol.
  • nicklouse
    nicklouse Posts: 50,675
    have you read the manual? as they are not hard to fit.

    also your terminology is interesting.
    bb retainer nut on that goes through the middle hole of crank on the non drive side
    bearing preload bolt?

    this is tightened before the pinch bolts. (think headsets) also have a read of the info on parktools.

    Ps if the crank is not against the bearing hit it harder.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • nicklouse
    nicklouse Posts: 50,675
    stephenroberts wrote:
    Do you have the shaft fitted the right way round?

    I believe there should normally be more length on the non-drive side.
    not possible with these cranks.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • arlowood
    arlowood Posts: 2,561
    Have recently fitted a new (2nd hand) R565 crankset to my bike. I had also replaced the existing 105 Hollowtech II Bottom Bracket with an Ultegra one purchase at a good discount.

    When offering up the drive shaft (integral with the chain rings so you can't mistake which way round it goes), I found that the splined portion went through the drive side bearing cup quite easily but thereafter the drive shaft itself was a very tight fit and required some "persuasion" with a wooden mallet to get it through to the other side.

    The crankset should eventually end up flush with the drive side bearing cup so if you have a space then you have not installed it fully. Get a bit of wood to protect the chainset and then give it a few hefty blows with a mallet until it goes through completely.

    Once it's through you should have no problem fitted the non drive crank arm and the bearing tension nut.
  • andyh01
    andyh01 Posts: 599
    I revisited this on Sunday. On closer inspection, what I thought to be a spacer sitting between the drive-side and bb cup was actually part of the inners of the old bb cup, when I originally took the cranks off the ball bearings dropped out, that’s how worn the cup had become. Once I took the remains of the bb off the crank shaft it went straight on.

    It also took me a while to figure out what the spare part that came with the new dura ace 9000 bb was for. Turns out to be the adaptor for the crank spanner as the o/s diameter of the cups are smaller, I also struggled at first to get the old cups off, I went and brought an external bb spanner for £12 before realising a chain-whip spanner would fit (brought an Aldi toolkit for £20) the old bb. I then had to return the bb spanner as I also couldn't get it to fit the new cups. I was advised by the LBS I needed the new proprietary tool that be £25, I was about to swap the bb for a standard one, before realising it comes with the adaptor that sits in the chain-whip and reduces the size of spanner to fit!
    The down side is;
    I managed to snap the hook off the safety catch,
    I've lost the o ring that fitted on the crank arm (non-drive side)
    but worse of all cross threaded the "bearing preload bolt" (wasn't sure how to describe that plastic screw that fits the middle of the crank.
    How critical is it for that to be square is it going to damage the bearing more as not even all the way round? :oops:

Categories