Bolt missing from bike..

stvn758
stvn758 Posts: 119
edited April 2011 in Road beginners
sunp0020g.th.jpg

There is a big bolt missing from the bottom bracket - the left pedal stem is being held on by sheer luck. My pedal was creaking so I put some grease on it and that seemed to work but having just had a proper look I was shocked to find my new bike falling to bits already.

Is there a name for this bolt?

Comments

  • emx
    emx Posts: 164
    the end cap is missing and you will need a new one, as it pre-loads the BB bearings. But there are two other bolts at the end of the l/h crank which should be under tension and it doesn't look like they are - these are what hold the crank arm onto the BB axle...
  • stvn758
    stvn758 Posts: 119
    sunp0018.jpg

    Thanks. Just ordered a replacement from Chain Reaction, wasn't as painful as I thought it would be.
  • rothers_bikeo
    rothers_bikeo Posts: 225
    This happened to a new bike ? What make is it and where did you get it from ?
  • stvn758
    stvn758 Posts: 119
    It's a Raleigh SF3.0, got it from Ash Cycles. I had to assemble it myself but the closest to that bolt I got was attaching the pedals. Someone at the factory must of messed up.

    Quite surprised it has fallen out.
  • rothers_bikeo
    rothers_bikeo Posts: 225
    As emx says to do it correctly you should tighten the end cap to specified torque (with the 2 crank arm side bolts loose) to correctly pre-load the BB bearings. Then tighten the 2 crank bolts evenly to lock the crank to the BB axle.
  • stvn758
    stvn758 Posts: 119
    Thanks for the help, long walk to work for the next few days I guess. :(
  • rothers_bikeo
    rothers_bikeo Posts: 225
    Provided the 2 crank side bolts are tight you will be fine to ride the bike. The end cap really serves no purpose once these are tightened, in fact on higher end Shimano cranks the end cap is plastic (the pre-load tightening torque is quite low).
  • Dmak
    Dmak Posts: 445
    It's perfectly fine and safe. Ride your bike.

    The missing thing is the bearing pre-loading bolt, it is plastic. As rothers says, it serves no purpose when the other 2 bolts are tightened.

    How you've lost it, not sure.

    I don't know the name of the actual part but I did just buy a tool for tightening it (preloading after service). A Shimano Hollow Tech II Crank Installation Tool TLFC16. From Ribble, they're good value.
  • on the road
    on the road Posts: 5,631
    The end cap is really just a dust cover.
  • stvn758
    stvn758 Posts: 119
    You were right, just tightened those side bolts with my Allen key and good to go. Being a complete novice I assumed that something that takes as much stress as your pedals would be attached by a huge bolt - especially when I saw the thread on the inside of the axle, but when it arrived seems to be just a nice little cover that screws in.

    That was a long walk for nothing, my ankles are killing me. :)
  • emx
    emx Posts: 164
    on the road wrote:
    The end cap is really just a dust cover.

    yeah, a dust cover which allows you to set the correct preload on the BB cups.....

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