Deraileur hanger adjust without tool?

wishitwasallflat
wishitwasallflat Posts: 2,927
edited March 2012 in Workshop
I recentely gave up on trying to fix a rear deraileur issue myself and put it in lbs - this upset me on so many levels (not just financial :!: :cry: ). They diagnosed and fixed a bent deraileur and hanger. I had suspected that was the issue but couldn't justify to myself (nor my wife) the cost of buying a deraileur hanger checking/adjustment tool. So ... now wondering if;
a) anyone has succesfully done this without the tool or
b) with a DIY alternative?

for minor misalingments (if it was major I am sure I could see it and bend it by hand I am thinking here of those minor misalingments that spoil shifting but are not of MTB crash and bash proportions) ?

Comments

  • nicklouse
    nicklouse Posts: 50,675
    As the thread is the same as a shimano rear hub axel you can remove he mech and screw in a spare rear wheel. This give a great guide and tool for sorting out the hanger.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • That seems like genius - may I check though just to be sure I understand the steps -

    1) fit axle of spare wheel to where the mech would go on the hanger -
    2) you can then eyeball easily if the extra wheel fixed to the hanger is parralel to the real rear wheel and
    3) use the extra wheel (gently) as a lever if needed to adjust hanger?

    If that's right it sounds easy and superbly simple!
  • keef66
    keef66 Posts: 13,123
    I'm kind of assuming you're talking about bending steel frames with the integral hanger?

    Not sure I'd trust an alloy hanger that had been bent and straightened
  • sungod
    sungod Posts: 16,852
    *slight* adjustment of an alloy hanger is ok, even a new one may need a tweak to get best alignment

    but if it's been bent much, best to replace
    my bike - faster than god's and twice as shiny
  • It was re an alloy hanger on an alloy frame I was asking about and yes its only a very slight adjustment - so slight that while I think I can see it is straighter now I couldn't really see any clear problem before - it certainly works way better now. I am guessing the extra wheel method would show any misalingment more clearly as one could compare the rims on the two wheels are parralel? The thing I am not sure of is there is so little axle protruding how do you fix it to the hanger?
  • nicklouse
    nicklouse Posts: 50,675
    normally there is 4-5mm that is all that is needed.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Many thanks nicklouse ! that's how much there is on the spare tiagra rear wheel I have so I can be independant of lbs on another bike job - very happy :D
  • nicklouse
    nicklouse Posts: 50,675
    just be careful. or if you wish you could move the axel through more but then you would have a wheel that would need sorting before being usable.

    but it is good to know that the shimano axels are 10X1mm (rear) other makes may not be.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Cheers defo will be careful and wouldn't want to move the axle unless I had to - hopefully it will just be a very very occasional job though only done rarely to check alingment if RD shifting gets ropey again (fingers crossed!)