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Resurrecting a pair of 7800 Dura Ace shifters

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Resurrecting a pair of 7800 Dura Ace shifters

Old 10-22-13, 06:48 PM
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Resurrecting a pair of 7800 Dura Ace shifters

Hello all,

I'm wondering if anyone has any pointers on doing this repair. What I have is a functioning L and R 7801 DA shifters and a L non-working 7800 DA shifter and a R partly working 7801 DA shifter. This R shifter only shifts 3 gears, or 3 clicks. I also have a working set of a L DA 7801 shifter and R DA 7800. If I get everything working I'll put the best set on my fav road bike and work the rest on my other bikes.

The reason why I want to give this a shot is cause I have a working set to reference on doing repairs. This is assuming that both the 7800 and the 7801 were both pretty much the same other than the smaller shift lever. I haven't done this before but I feel that I'm capable of doing it. I just could use a little guidance, a good .pdf file or two and maybe a video or two. I haven't really started looking what I can find online but will be doing so after posting this.

If you got anything you think that would help, I'd sure appreciate a response on this.

Thanks for reading this and much appreciated.
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Old 10-22-13, 07:42 PM
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http://techdocs.shimano.com/techdocs...34374302051957
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Old 10-22-13, 08:20 PM
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i would try a little wd40 or similar product in the shifter. there are a few guides to opening up some older shifters on here. opening the 7800 will be similar
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Old 10-23-13, 04:09 PM
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Yeah I tried the WD40 shower on the shifters yesterday and let them sit over night. They still were working the same, but I was able to notice that there were a few strands of wire on the shifter. This was the back shifter,




Looks like I'm going to have to wave the white flag on this. I can't get this nut off. Not sure why they would design this like this.



I contacted Shimano regarding a nice .pdf file on the assembly of this shifter and they said there isn't one cause they aren't that easy to get back together correctly. I'll give it a little more of the good o college try, but it doesn't look good. If I don't get it apart correctly I'll just get really caveman on getting this apart and see what everything looks like, but I'm sure I'm just going to write this off.
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Old 10-23-13, 05:02 PM
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i will now assume there is a broken cable head inside if so then go to the drill extraction method. search and you will find the drill location. what is the history of these shifters? you can also try tweezers to pull on the strands and then hitting the shift lever the rewind the wheel/carrier
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Old 10-24-13, 12:11 PM
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Originally Posted by reptilezs View Post
i will now assume there is a broken cable head inside if so then go to the drill extraction method. search and you will find the drill location. what is the history of these shifters? you can also try tweezers to pull on the strands and then hitting the shift lever the rewind the wheel/carrier
I'm not sure what the "drill extraction method" is. I searched for it but didn't find anything. Here's another pic of what I'm dealing with. You are looking at as you would if on the bike.



The history of the shifters are that I bought two pairs at different times. They (1/2) were advertised as non-working at the time. They looks fairly good and not all beat up. I have a good miniature needle nose pliers and I tried working on getting out as you described. I'm thinking the cable head is inside, about 180 degrees from where the cable end is coming out at. That part of the mechanics you see on the left of the pic, that rather large piece of aluminum is blocking me from getting at it.
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Old 10-24-13, 12:22 PM
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Old 10-25-13, 04:53 AM
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This is exciting - keep going!

I've always heard that Shimano brifters can't be fixed by mere mortals.
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Old 10-25-13, 05:36 AM
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It ain't so. There's an easy way.

Don't go drilling holes willy-nilly, there's no need for that.

You're almost there, in fact you've kinda gone too far. Reassemble the back of the lever so the brake lever pivot bracket is retained by the castellated nut, this will hold everything together.

Now, move the flipper aside to expose the pillips screw, undo that and the large lever slides off the whole assembly.

Removing the remains of the cable is now a doddle, and you can clean and lube the mechanism without disassembling it further. Pay particular attention to the tiny pivots of the hairsprung pawls, this is where they stop working.

Look at the first link in my tag for more.
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