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Rivnut In Downtube

womackwomack Posts: 566
edited May 2021 in Workshop
As title suggests I had to Dremel a broken bottle cage rivnut with the result that the residue is in the Downtube.

Is it a given that all downtubes will be hollow at the bottom and with removal of the BB it will fall out or could they be solid at the bottom?

Edit. I would ignore it but it makes a right noise!

Posts

  • WheelspinnerWheelspinner Posts: 5,946
    Depends a *lot* on the frame, cable routing and BB type: carbon, aluminium, steel, internal cable or external and threaded or press-fit BB?

    If it’s external cable and threaded BB I’d say you are likely to be unlucky. The BB shell is often a cylinder with only a drain hole in the bottom either welded or bonded into the frame, but no hole on the downtube side.

    If it’s internal cable routing and/or press fit BB you might be ok
    Open O-1.0 Open One+ BMC TE29 Titus Racer X Ti Seven 622SL Kestrel RT1000 On One Scandal Cervelo RS
  • oxomanoxoman Posts: 10,729
    Depends on whether the frame has been pierced internally at the bottom bracket tube / junction. Some do it for internal routing and some don't, head set is another possibility but again the above applies. I have seen people fill their frame's with foam or a bit of resin to stop problems like this but personally i wouldn't want to be doing it. Good luck.
    Too many bikes according to Mrs O.
  • imposter2.0imposter2.0 Posts: 11,888
    womack said:


    Is it a given that all downtubes will be hollow at the bottom and with removal of the BB it will fall out or could they be solid at the bottom?

    There's only on way to find out...

  • womackwomack Posts: 566

    womack said:


    Is it a given that all downtubes will be hollow at the bottom and with removal of the BB it will fall out or could they be solid at the bottom?

    There's only on way to find out...

    Yes, you are correct. Would need to go and buy the correct spanner first.

    It is a 10 year old Allez Sport, aluminium with external cables. It has Sora nine speed and I think the BB is what people call Hollowtech.

    I don't have the bike at home at the moment so can't verify that.
  • masjermasjer Posts: 1,518
    If you can't remove from the BB area, maybe the head tube? You could possibly remove some debris with a vacuum cleaner attachment over the bolt hole- with bike upside down
  • sungodsungod Posts: 14,650
    if there's no exit hole at the bb or head tube...

    if the rivnut remains are steel, you can use a strong magnet to drag them back to the hole

    if they'll fit through the hole, easy, otherwise perhaps you can cut/grind them to fit - grab with fine pliers, use the dremel
    my bike - faster than god's and twice as shiny
  • MattFalleMattFalle Posts: 10,096
    This happened on N1 bike about 15 years ago.

    it rattled and rattled amd rattled and one day it stopped all by itself.

  • womackwomack Posts: 566
    edited May 2021
    MattFalle said:

    This happened on N1 bike about 15 years ago.

    it rattled and rattled amd rattled and one day it stopped all by itself.

    To be honest have already put new rivnut in down tube so old one won't come out that route.

    I have some white grease which dries solidish and gloopy so I may well straw spray some down through the bolt hole and see if the remains of the nut get stuck in it.
  • pilot_petepilot_pete Posts: 2,120
    Yep, spray some glue down there which will grab all the bits and stop them rattling...
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