Chainring bolts to mount rear derailleur?

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HaakonJohansen
Posts: 284
Joined: Mon Sep 01, 2014 4:58 pm

by HaakonJohansen

Does anyone know if any chainring bolts use the same thread pitch as MTB derailleur mounting bolts? Like for example these ones?

mattr
Posts: 4671
Joined: Fri May 25, 2007 6:43 pm
Location: The Grim North.

by mattr

Aren't chain ring bolts M8? Rear mech is M10.

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HaakonJohansen
Posts: 284
Joined: Mon Sep 01, 2014 4:58 pm

by HaakonJohansen

Most of them are m8, but not all (i.e. those in the link), but I'm not sure about the length and the pitch. I've got myself the Goatlink 11, which comes with a steel bolt for some reason, so that's why I'm looking for an alu bolt. I'm also looking at this one (the "Befestigungsbolzen"), but I need a head diameter no bigger than 14mm, and although fantic26 does deliver some great products, they are notoriously bad at answering emails:S No problems with deliveries though.

bikemaniack
Posts: 331
Joined: Thu Jul 16, 2009 9:33 pm

by bikemaniack

Maybe bolts for ram (XX) chainrings maybe are M10.

HaakonJohansen
Posts: 284
Joined: Mon Sep 01, 2014 4:58 pm

by HaakonJohansen

bikemaniack wrote:Maybe bolts for ram (XX) chainrings maybe are M10.

You're right, they are. I'm still not sure about the thread pitch though. Also, the ones that Sram makes themselves are too short. 5mm length of the threaded area I think, and I need 8mm.

HaakonJohansen
Posts: 284
Joined: Mon Sep 01, 2014 4:58 pm

by HaakonJohansen

Problem solved! I got fantic26.de to make a hanger bolt for me with a smaller head diameter than the standard one to fit the Goatlink11;)

Jaker
Posts: 701
Joined: Wed Nov 01, 2006 4:55 am
Location: Vancouver, British Columbia, Canada

by Jaker

What'd they charge you? Have you rcvd the bolt yet? I want to do the exact same thing.

HaakonJohansen
Posts: 284
Joined: Mon Sep 01, 2014 4:58 pm

by HaakonJohansen

Jaker wrote:What'd they charge you? Have you rcvd the bolt yet? I want to do the exact same thing.

I haven't received the bolts yet, but their on their way. They didn't charge anything extra;) They drill away some material from the bolt head of the "befestigungsbolzen" in this link. I don't know if they'll do the drilling before or after the anodizing though. But the edge of the bolt head won't be visible with the Goatlink11 anyway, so it doesn't really matter. They also sell the "gelenkbolzen" for the XTR M9000, although not available on their website yet. They told be to order the bolts from the link above, and write a comment saying that I want the XTR M9000 version of the gelenkbolzen, and the desired head diameter of the befestigungsbolzen (I ordered 13.8mm).

FatherLuke
Posts: 1
Joined: Mon May 09, 2016 5:07 pm

by FatherLuke

HaakonJohansen wrote:Problem solved! I got fantic26.de to make a hanger bolt for me with a smaller head diameter than the standard one to fit the Goatlink11;)

Dude, you are my hero! Looking for the same stuff and here you are with your solution! :)
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HaakonJohansen
Posts: 284
Joined: Mon Sep 01, 2014 4:58 pm

by HaakonJohansen

Nice to see others looking for the same thing;) Strange that the Goatlink Isn't already supplied with an alu bolt really.

HaakonJohansen
Posts: 284
Joined: Mon Sep 01, 2014 4:58 pm

by HaakonJohansen

Just got the bolts. Here is a picture if anyone is interested. As you can see the cable housing is too short now, so the picture is just meant to show the derailleur;P

Image

CGT
Posts: 342
Joined: Fri Jan 05, 2007 5:33 pm
Location: Stockholm, Sweden

by CGT

That looks clean! Are those titanium or aluminium bolts (both the one that connect the RD to the Goatlink and the Goatlink to the frame)?

HaakonJohansen
Posts: 284
Joined: Mon Sep 01, 2014 4:58 pm

by HaakonJohansen

CGT wrote:That looks clean! Are those titanium or aluminium bolts (both the one that connect the RD to the Goatlink and the Goatlink to the frame)?

Both are aluminium. To install them, you need a 6mm hex key instead of the 5mm on the standard Shimano bolts.

CGT
Posts: 342
Joined: Fri Jan 05, 2007 5:33 pm
Location: Stockholm, Sweden

by CGT

Thanks for your reply. Did you measure the weight saving? Are the standard M9000 bolts aluminium or steel?

HaakonJohansen
Posts: 284
Joined: Mon Sep 01, 2014 4:58 pm

by HaakonJohansen

CGT wrote:Thanks for your reply. Did you measure the weight saving? Are the standard M9000 bolts aluminium or steel?

Standard ones are aluminium too. I didn't measure the savings, as my scale can't measure anything smaller than two gram intervals. The bolts are a bit lighter I think though. The one mounting the derailleur to the frame is extremely hollowed out, So I would guess that one to be quite a bit lighter (not more than 1-3 grams, but relative to it's weight it's quite a lot). The GoatLink11 is heavier than the standard Shimano link though, so in total I think I might have gained a little weight, but not more than a gram or so. My scale was changing a bit between 14 and 16 grams for the GoatLink with the new bolts, so I guess its around 15 grams, while it showed 14 for the standard Shimano link with the Shimano bolts. If you only wanna shave off some weight and gain some bling, drop the GoatLink11 (it does add a bit of bling too though :lol:) and just order the bolts in the colour you want :wink:. The GoatLink does seem to improve the shifting on the smallest cogs a bit though. Remember to adjust the H and L bolts as well. Not just the B-tension bolt.

by Weenie


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