Tyre rubbing chainstay- Safe fix or not?

onionmk
onionmk Posts: 101
edited April 2017 in Workshop
So I built a commuting bike up recently with bits I had around. It's a merida ride lite 94 (Alu Frame). Anyway, the rear triangle seems to be misaligned as the wheel sits closer to the non drive chainstay and rubs when I use 28mm tyres. I'm quite sure its the frame and not the dishing of the wheels because:

1. Same wheels sit fine on another frame
2. Tried another wheel in the frame and same problem occurs
3. Wheels were laced and dished recently.

My proposed fix- Get my LBS to dish the wheel 2mm to the right side. I don't want to bend an Alu frame and risk catastrophic failure especially given that I need to rely on this bike to commute. The question is- Is it safe to dish the wheels even more to the right?

I'm running 9 speed if that helps. Wheels are cheap shimano so not fussed about longevity as they can be easily replaced.

Thanks in advance!

Comments

  • jgsi
    jgsi Posts: 5,062
    I'd sort the misaligned frame out, me I would.
    I may be wrong, but it'll ride "p issed" as it is.
    To get this way, the frame has been bent previously?
  • tangled_metal
    tangled_metal Posts: 4,021
    If you're worried bending the stay back would cause damage are you not worried the damage was already caused by whatever misaligned the stay?

    Basically it got bent out of shape already, damage done. Would bending it back into shape not kill or cure it? If it does cause damage sorting it out then how safe was it in the misaligned state?

    BTW I'm no expert in anything bike related so ignore me and wait for a better reply. I'm just curious as to why bodge the wheel to get around a damaged/bodged frame?
  • onionmk
    onionmk Posts: 101
    Tangled Metal wrote:
    If you're worried bending the stay back would cause damage are you not worried the damage was already caused by whatever misaligned the stay?

    Basically it got bent out of shape already, damage done. Would bending it back into shape not kill or cure it? If it does cause damage sorting it out then how safe was it in the misaligned state?

    BTW I'm no expert in anything bike related so ignore me and wait for a better reply. I'm just curious as to why bodge the wheel to get around a damaged/bodged frame?

    Sometimes the frames come misaligned from the factory- I expect eth frame was intended for 25mm tyres in which case this issue would be undetectable. If it's the case that it had been bent afterwards then yes, some damage has been done. But the problem is the more you bend it the more you weaken the metal and cause more damage.

    I'd prefer to dish the wheel as its a lot less hassle and probably safer than messing with the frame.
  • apreading
    apreading Posts: 4,535
    Bending aluminium once is often not so bad. Bending it back is often catastrophic. I think the first bend tends to compress the metal in the inside of the bend. Second bend, rather than stretch it back out again causes tears.

    Not sure about deliberately dishing the wheels to compensate - I have no idea and cant comment on that!
  • Guernsey Donkey
    Guernsey Donkey Posts: 144
    Have you tried putting the wheel in the other way round? that will tell you if it is the dishing or the frame.
  • keef66
    keef66 Posts: 13,123
    I'd second the advice about not trying to bend anything aluminium, especially if there's achance it's already been bent the other way. Can you not fashion some kind of spacer to sit in the NDS dropout and correct the alignment? Surely be a lot easier than redishing the wheel.
  • AK_jnr
    AK_jnr Posts: 717
    Sounds as simple as you trying to fit 28's in a frame that wasnt designed to take that size... Use 25's and save the hassle.
  • svetty
    svetty Posts: 1,904
    AK_jnr wrote:
    Sounds as simple as you trying to fit 28's in a frame that wasnt designed to take that size... Use 25's and save the hassle.

    +1. Just use 25mm tyre on the rear
    FFS! Harden up and grow a pair :D
  • onionmk
    onionmk Posts: 101
    Thanks for the advice guys. I've tried the wheel the other way round and the problem still occurs so it's definitely the frame. I think I'll go with redishing the wheel. My LBS can do it quickly and easily.

    I read up that 11 speed wheels are dished more aggressively vs 9 speed to accommodate a wider cassette with no problems with wheel strength/stiffness etc.
  • ridgerider
    ridgerider Posts: 2,852
    How about swapping washers around on the axle to move the wheel across a bit?
    Half man, Half bike

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