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Bent Boardman Frame dropout??

kevinharleykevinharley Posts: 554
edited September 2013 in MTB workshop & tech
Hi all,

I've a Boardman Team Hardtail, which I've had for about 18 months. Some time ago, I got a big stick caught in my rear mech, which I think twisted both the mech hangar and the mech. I bent the hanger back as best I could, and tried to adjust the mech ... it was never right, but I put that down to my inability to properly set up / index the gears! :oops: Shortly afterwards, I changed to singlespeed in any case, so didn't really pursue it any further.

Yesterday, I decided to replace the mech hanger - I thought that it was flexing too much, causing the chain to go slack when running singlespeed. I decided to replace it because I figured that the mech hanger was perhaps weaker, due to the original impact and / or subsequent twisting it back into position.

The new mech hanger wouldn't fit - it doesn't 'seat' properly in the 'cut-out' of the frame where its meant to be located. It is held to the frame by two small hex screws, but its impossible to properly align both of these; either one or the other can be screwed in, but not the second. If you hold the new mech hanger over the old one, there is a slight, but distinct difference in their outline shape (the dropout / opening for the wheel axle is larger on the original; and the section where the hanger is screwed to the frame is slightly bent rather than flat)

It's possible that there is a fault in the manufacturing of the new mech hanger, but I doubt it. It looks more like the drop-out on the frame has also slightly twisted (along with the mech hanger, and I believe the rear mech itself) at the time of the original argument with a beefy stick! I know that this is perhaps unlikely, and not how frames and hangers are designed (the hanger is meant to break in order to protect the frame etc) ... but that's my current working hypothesis ...

Anyway, I've just taken it into Halfords, and they will have a proper look at it today, but I'm just after some advice so I can go armed with information in case they try and fob me off (I'm not necessarily expecting this; I'm a fairly regulr customer, and have found the staff at this particular store helpful; knowledgeable and responsive in the past! :wink: )

So, any advice / views on the following:

1.) How likely / plausible is my working hypothesis, ie that the mech, hanger and dropout all bent 'as one' rather than the hanger snapping as it was supposed to? Anyone experienced / know of something similar?

2.) If the frame has bent, would / should this be covered under the warranty on the frame (I'm the original owner, the bike is under 2 years old, and I understand the frame is covered by a 2 year warranty)

3.) If it is a bent frame, but not covered by the warranty (or Halfords dispute this), would it be safe to continue riding, and cobble together a fit of the new mech hanger by filing / bending it to fit the frame and / or bending back the rear of the dropout of the frame?

Thanks

Posts

  • supersonicsupersonic Posts: 82,708 Lives Here
    Not sure I understand a couple of things!
    I thought that it was flexing too much, causing the chain to go slack when running singlespeed

    If you are running single speed, then the tensioner you will be using will take up the slack. If you are not using a tensioner, then you will be bypassing the hanger altogether.

    Either way it seems you have the wrong hanger.
  • nicklousenicklouse Posts: 50,675 Lives Here
    sounds like you have the wrong hanger.

    you getting a stick in the mech is not a warrenty issue.

    no idea with out seeing it.
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  • kevinharleykevinharley Posts: 554
    supersonic wrote:
    Not sure I understand a couple of things!
    I thought that it was flexing too much, causing the chain to go slack when running singlespeed

    If you are running single speed, then the tensioner you will be using will take up the slack. If you are not using a tensioner, then you will be bypassing the hanger altogether.

    Either way it seems you have the wrong hanger.

    Sorry - not clear, I agree.

    I run a DMR ss conversion kit like this:
    http://www.chainreactioncycles.com/Mode ... elID=10009, ie using a Simple tension seeker, that bolts to the rear mech hanger. I set the tension of the chain, bolt up the tensioner, and it should keep the chain in tension throughout a ride .. but it doesn't, it goes a bit slack. If I turn the bike upside down, put my hand on the chain and put pressure on it, you can see the mech hanger flexing, and the chain in turn becomes slightly slacker.

    I don't have the wrong hanger - its a direct replacement for the one I already had.

    Re the warranty issue ... maybe (probably!) I'm being naive, but I guess I had hoped that, given the mech hanger is designed to do the breaking on impact, in order to protect the frame itself, in this case the bike hasn't reacted to the stick like it was meant to, and that the frame should withstand that kind of incident ...?
  • supersonicsupersonic Posts: 82,708 Lives Here
    Ah, I assumed the tension arm was sprung. The frame may be bent, just don't tell Halfords you tried to bend the hanger back lol.
  • kevinharleykevinharley Posts: 554
    supersonic wrote:
    The frame may be bent, just don't tell Halfords you tried to bend the hanger back lol.

    Better hope they're not reading this then! :oops:

    So, if the frame is bent, do you reckon there's a possibility this is covered by warranty, or at least suggesting that Halfords might consider that??
  • thelonegrooverthelonegroover Posts: 1,073
    First you said: 'If you hold the new mech hanger over the old one, there is a slight, but distinct difference in their outline shape'

    then: 'I don't have the wrong hanger - its a direct replacement for the one I already had'.

    If it's different, how can it be the same? Surely, it's one or the other.
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  • UliUli Posts: 190
    If you nice to them they may be nice to you so give it a go and be polite. I saw some people making complaints about Boardman frames so that may be your advantage as well. I managed to get some parts replacements after warranty where it wasn't exactly manufacturer fault :)
    And yes make sure you have the right hanger.
  • kevinharleykevinharley Posts: 554
    First you said: 'If you hold the new mech hanger over the old one, there is a slight, but distinct difference in their outline shape'

    ... Because the old mech hanger has bent, making it a slightly different shape to the new one ...

    As it hapens, just had a call back from Halfords; they do believe that the drop-out of the frame has bent slightly too ... the options are to stick with the current mech hanger (bent, but which still fits the (also bent) drop-out of the frame), or to bend the new mech hanger so that it too fits the bent dropout! They say the frame doesn't need replacing, and it wouldn't be covered under warranty anyway ...

    Oh well .. the bike has long-since passed its showroom condition, so I'm not worried about it being 'imperfect' ... but still worry that the drop-out will have been slightly weakened too, and might break at some point ...
  • Just to resurrect my own thread, for some further advice.

    I'm about to put the gears back on my bike for a forthcming trip to the Lakes.

    The rear drop-out on the frame HAS bent slightly; this means that the rear mech will not be properly aligned. I am intending to try and bend the drop-out back, so that the mech hanger fits better, and the mech itself will be aligned as it should be. Obviously, I will be nice and gentle with it, but do you think there is a significant risk that I could break the drop out instead?

    Cheers
  • cooldadcooldad Posts: 32,599
    Yes
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  • nicklousenicklouse Posts: 50,675 Lives Here
    again without seening it is is hard to say.

    as you say you are short of cash. what are you going to do if it does fail?

    leave it SS.

    but again without seeing it who knows.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
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