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I disassembled my dual pivot side-pull and can't put it back together!
#1
Any help much appreciated! I disassembled my Shimano Sora BR-3400 dual pivot side pull rear caliper.

For some reason, the bolt that runs through the whole caliper in the centre gets thicker and will only allow the middle bit of the caliper to go onto it. See pictures.

[attachment=4957]

[attachment=4958]

[attachment=4959]

Any suggestions?
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#2
Try this:

http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/BR/EV-BR-3400-2749_v1_m56577569830625608.pdf
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#3
Did you loosen the set screw in the aluminum part with two holes through in your pictures before dis-assembly? Based on the condition of the main bolt and the fact that it is still in place in your pictures - I would guess not.

I do not know if the bolt is salvageable or not.....It is Shimano Code No. Y-8E7 98050 on the document RB shared.
Nigel
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#4
Right. The threads appear to be flattened by the set screw.
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#5
Basic Mechanic's rules:

1. Look before you wrench. See how things are put togehter and interact.

2. If there are instructions or any other reference available for something you have not done before be smart enough to use it.

3. If it's hard to move something try a bit harder. Then if still a problem stop, look and think, get a 2nd opinion before proceeding.
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#6
Basic Mechanic's rules:

1. Look before you wrench. See how things are put togehter and interact with each other. Take apart only what is necessary.

2. If there are instructions or any other reference available for something you have not done before be smart enough to use it.

3. If it's hard to move something try a bit harder. Then if still a problem stop, look and think, get a 2nd opinion before proceeding.
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#7
Thanks everyone for your replies. Really helpful. I'm learning the hard way and will take note of the basic mechanics rules from now on!

Yes, I didn't remove the set screw before I disassembled and obviously it has messed up the threads of the main bolt. So, I guess I need to get a new main bolt? I also *may* have forced the rear bit of the caliper and the nut behind it onto the main bolt. Are we thinking they are probably ruined as well?

Thanks again everyone.
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