Lightest front derailleur? (road 2x)

Discuss light weight issues concerning road bikes & parts.
alcatraz
Posts: 1797
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

Hi WWs

I found that a dura ace 7900 derailleur is 66gr (braze on) so I'm now finding myself looking for one. It struck me though that there might be lighter ones out there. Do you know of any? (without resorting to limited crazy hard to find items)

I don't mind mixing components. I run a sram drive train and only recently found out that front derailleur action is super smooth even when using an ultegra front derailleur with the sram shifters.

I'm currently on 10s.

Thanks for reading
/a

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prendrefeu
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by prendrefeu

Tiso Altore can be tuned down to ~45g more or less.
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by Weenie


Wookski
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Joined: Tue Feb 23, 2016 5:51 am

by Wookski

Old record derailleurs could be tuned to sub 45 as well

Jenmoss
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Joined: Wed Oct 25, 2017 10:15 am

by Jenmoss

The lightest one here is actually 47 graImagems the others are in the 50s
No idea why it’s that light ,the one with the split in the cage.

alcatraz
Posts: 1797
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

Tiso is hard to find, old campy must have a wider cage than necessary for narrow chains.

So is it true that from 9-11 speed fd's, shimano 7900 is probably the lightest?

/a

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4ibanez
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by 4ibanez

If you want the lightest you might need to be patient. Also depends what shifters you use. Shimano/Sram shifters aren't compatible with Campy FDs (ratios are problematic I've heard). I don't think the width of a Campy 10s FD will be any different to an 11 (using an all Campy setup). There's going to be easily enough adjustment to shift all the way over the big ring.

graeme_f_k
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by graeme_f_k

4ibanez wrote:
Sun Jan 28, 2018 9:02 pm
If you want the lightest you might need to be patient. Also depends what shifters you use. Shimano/Sram shifters aren't compatible with Campy FDs (ratios are problematic I've heard). I don't think the width of a Campy 10s FD will be any different to an 11 (using an all Campy setup). There's going to be easily enough adjustment to shift all the way over the big ring.
Old thread but for reference - Campag 10 and 11s FDs have significantly different width and shape gates.
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alcatraz
Posts: 1797
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

I did get a 7900 in the end and it's 66gr spot on.

Tuning is a bit beyond me I'm afraid. I run 10/11s systems so I need that cage width.

Thanks for all the replies.

/a

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themidge
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Location: yer ma

by themidge

My 7900 FD is 66 grams too, props to shimano for consistency. It even matches the claimed weight! :thumbup:
Correct me if I'm wrong but I think it's the lightest un-tuned. I know record and tiso etc. can be tuned lighter, but stock..?

Nozes
Posts: 45
Joined: Tue Nov 05, 2013 1:56 am

by Nozes

I'm currently looking for a light FD, and the 7900 looks really good, but I've read somewhere that it's got a diferent cable pull from other Shimano.
I'm using Sram Rival 22 shifters, would it work?

Wookski
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Joined: Tue Feb 23, 2016 5:51 am

by Wookski

Nozes wrote:
Sat Dec 15, 2018 12:44 am
I'm currently looking for a light FD, and the 7900 looks really good, but I've read somewhere that it's got a diferent cable pull from other Shimano.
I'm using Sram Rival 22 shifters, would it work?
Why bother when you’re running Rival?

RussellS
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Joined: Wed Feb 03, 2010 1:31 am

by RussellS

Agree with Wookski. If you're running SRAM Rival 11 speed, then obviously bike part weight is not your sole focus in life. What is the point of trying to save 10-20-30-40 grams on a front derailleur by going with old time 7900 10 speed? I suspect 10 and 11 speed front derailleurs are cross compatible. But why bother?

Nozes
Posts: 45
Joined: Tue Nov 05, 2013 1:56 am

by Nozes

I thought this was weightweenies? 🙄
Yes, I'm searching for a 20+ grams lighter FD,and the 7900 can be found used at decent price.
Rival shifters fit my budget build very well and they work.

Check out my bike here: https://weightweenies.starbike.com/foru ... 0&t=154636

alcatraz
Posts: 1797
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

I have a 7900 with sram red shifters and the problem is that you don't get enough cable pull to eliminate chain rub in both small/big + big/small.

There is a trick I haven't tried yet and it's to attach the cable further down on the FD arm. That increases the movement for a given cable pull. You may need to play with some washers to get it right.

With 2x you don't really need to worry too much about indexing, just attach the cable a bit further down should be enough.

Good luck.

by Weenie


Nozes
Posts: 45
Joined: Tue Nov 05, 2013 1:56 am

by Nozes

Thanks @alcatraz.

It doesn't sound that good, to be honest. I may try to find a Red FD instead,as it's not that heavier and should not have any compatibility issues.

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