IceTee2

I was given a 2005 Trek 520 bare frame except for the front derailleur, a Shimano 105 series (FD5504 clamp-on). I want to use a straight mtb handlebar with mostly Alivio components. I am planning to use the following major components:

• Alivio Crankset FC-T4010, 48-36-26 (originally 105 50-42-30)
• Altus shifters SL-M2010 (originally bar ends)
• Alivio rear derailleur RD-M4000-SGS w/ 11-32 cassette

My question is: Can I use the 105 front derailleur with this setup? I tried to get the Alivio FD-T4000-DS3 but cannot find one anywhere. An alternative would be the Altus FD-M371-3 which is available.

This project was intended to keep me occupied in my retirement. It's the wrong frame size for me, 17") so I'll try to sell it or maybe give it away. I'm 75 years old so please be gentle with your responses....and thanks for the help?

alcjphil

The 105 front derailleur will not index correctly with an Altus shifter. As well it may also be designed for a double crankset, not the triple you plan on installing
The good news is that 105 derailleurs are good quality, well worth using on a future project

dedhed

Generally Shimano road FD don't play well with mountain shifters. Nearly all Shimano RD up to 9s Mt and 10s road don't care if road or Mt. shifters. So in theory your options are flat bar road shifters or a Mt series FD. Theoretically a Mt FD will be a better option as they are usually shaped for the smaller rings used on Mt triples.

IceTee2

The 105 FD that I referenced is/was standard equipment on the 2005 Trek 520. It has the “extra” bulge on the cage to get to the granny ring. The RD was indexed (SIS) with the bar end shifter but the FD was friction only.

alcjphil

What you should be looking at are Sora flat bar shifters. They make a version for triple cranks
Your front derailleur had a friction shifter, that doesn't mean that it was friction only

wheelreason

That's an older 105 "9 speed" triple dlr, it will work with your set up unlike most of the newer 105s, you might need to tweek it a touch though.

IceTee2

I compared the105 to my Deore XL equipped 1995 520 and the cage is exactly the same in physical size and profile. I appreciate your reply to my question. Be Safe...

wheelreason

Those 90s 520s were tanks, we sold a bunch of them.

Kontact

He was talking about the length of the arm the cable attached to and how that affects indexing.

IceTee2

I presumed, maybe incorrectly, that a FD that that accommodated a 3 chainwheel (52-42-30) capacity would have the same 'swing' whether using a friction shifter or an index shifter. That said, I've been wrong before...

Kontact

Not true of either front or rear derailleurs.

Bill Kapaun

They should both travel the same "arc", but that's really not the issue-
INDEXED Road vs Mountain FDER's require different cable pull for some reason. Mountain vs Road INDEXED RDER/shifters (up to 9 speed) are compatible.

ANY "indexed" derailleur can be used with a friction shifter. Absolutely don't rely on the reverse being true.

IceTee2

If I'm hearing you right, I'm only considering down pull derailleurs since that's the way the original cable routing on the rem 520 was configured. My understanding is that mountain bike have cable routing coming down to the FD from the top tube so they use upswing FDs. I have no idea what uses a side swing but I know it's not me!

Kontact

Nope, nothing to do with top vs bottom pull derailleurs. This is about the amount of cable pulled by the shifter pér position.

But you don't really need to understand why a road shifter is incompatible with a MTB front derailleur for that to be the truth.

Bill Kapaun

There's Bottom or Top pull. Don't worry about "swing".

If making large changes in chain ring sizes, then you may want to look for a FDER that's curved more appropriately for that size.
Such as a 28-38-48 vs 22-32-44.
You can mismatch quite a bit and make them work.Maybe not real well, but enough to complete a shift.
This is a 22-32-36 on my hybrid. It shifts, but needs a bit of help.
I put a 22-32-38 on my first Rockhopper (everything else IDENTICAL) and it shifted reasonably well. A 40T and I probably wouldn't have noticed with my riding style.

And before anybody asks- Yes it's a wide gap between the big ring and the FDER. Once you figure out how to reduce it without the FDER not clearing the middle ring, I'm all ears.

IceTee2

My problem is that I want to build each bike like it will be my own and that's troublesome with respect to the old credit card balance. I'm a right side below the knee amputee and since I have no feeling in my prosthetic, I have to clip in to keep my foot on the pedal. Sadly, I've abandoned two wheels for an Ice Sprint X recumbent trike.

I have all th parts as of today and I'll keep posting fro informational purposes and entertainment for the that actually know what they're doing.