Anybody else trashing front derailleurs?

I’ve been using TrainerRoad almost exclusively for about 3 years (around 1,000 hours of indoor training at this point). In that time I’ve replaced my front derailleur twice, and I’m at the point where I should probably do it again. I ride on rollers and use the power-meter on my bike (PowerTap G3 hub). Since I ride on rollers I use my front derailleur a handful of times each ride.

The pattern has been the same in each instance - the derailleur simply gets harder and harder to shift until it simply won’t shift with the lever anymore. Sometimes I can resurrect it with WD-40 and lube and manually working out the stiffness. The problem is definitely with the derailleur itself and not the shifter or the cable. I’m at the point now where I’m spraying some WD-40 on it after every ride which seems to be working pretty well.

I’ve never had my sweat rate tested, but I surmise that I’m a bit above average. I can only conclude that the occasional drop of sweat that hits just the right spot on the derailleur is to blame for the stiffness over time which, while annoying, makes total sense to me. I’m mainly curious if anybody else has experienced this. I searched the forum but found no other posts about this.

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that’s why I went to this setup seven years ago – a fixie and a powertap hub. less to sweat-nuke.

I kill an Ultegra front mech each year. The rear gets about two years (sweat I can’t clean out of the spring unless I remove it, which I am too lazy to do)

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What’s a “front derailleur”?

Ok, got that out of the way.

I’d try putting a blob of grease on the pivot and spring, effectively “sealing out” sweat.

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I’d suggest using something better for lube, like Tri-Flow or something similar. I’m no fan of WD for use in a bike.

Then consider if you have sufficient cooling. Dripping large amounts of sweat is not desired for a number of reasons, and damage to bikes is a key one.

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For what it’s worth, “front derailleur” is the nomenclature used by the Shimano manuals (e.g. this dealer’s manual and this one as well.) :stuck_out_tongue:

For everyone:

What do you do for sweat management? Maybe I’m lucky, but most of my sweat drips down my arms or off of my face, with both routes ending up on the folded bath towel on my handlebar. Very little sweat hits my bike at all.

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My thought with the WD-40 was for the “water displacement” aspect to push the sweat out of the sensitive bits. For lube I’ve been using Rock N Roll Gold (which is what I use on my chain), but I wonder if it’s too thin to really protect. How thick is Tri-flow? Perhaps something heavier like @Quadzilla_Jr suggested would be better.

On the cooling front I use a centrifugal air mover along with another big axial fan. It feels adequate to me except in late summer (I live in the south).

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Take a peek at the spring inside a new Shimano rear derailleur. at the grease in there. It’s THICK. Something like that is what I was thinking.

Sweat runs down my arms and drips off my hands so I wrap bar towels around my handlebar (one for each hand). Sweat pours off my face so I use a sweat band or a wicking cycling cap. Sweat also runs down my back and drips through my shorts, but I haven’t found any way to combat that. After most rides I wipe down my bike with a damp (i.e. not sweaty) bar towel.

Go 1x. I haven’t had any front mech related issues since I did.

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Don’t ever use WD-40 on your bike as a lubricant…it sucks. Will work (very) short-term, but then gums up and actually works in the opposite manner in which you intend. It really is better suited as a cleaner, not a lubricant. For example, I will use it to do a “quick clean” on my drivetrain occasionally and wipe it down thoroughly with a rag and THEN apply a lubricant to the chain.

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I think my initial post was ambiguous on this point. My thought with the WD-40 was for the “water displacement” aspect to push the sweat out of the sensitive bits.

…Because you’ve stripped the shifter, replaced the cable and cable housing?

Id definitely be looking at those first.

Then strip the front derailleur, clean and degrease it, leave it a while, relube, test it and then put it back on.

Gotcha…but if you are still using it after every ride, you are likely contributing to it’s demise, not preventing it. Others have mentioned using grease in appropriate areas and that would provide more protection than W-40 or a lubricant.

Do you use a bike thong in addition to the towels? if not, maybe give that a whirl to try and catch some sweat before it gets to the FD.

The WD may remove the sweat. Regardless, I think you should be adding lube after the fact and on a regular basis. Tri-Flow is likely close to the consistency of WD, but TF is a great lube where WD is not.

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If the bike is sitting on a trainer and not being removed regularly you could probably coat the whole thing in a heavy grease so the water and sweat can’t penetrated the pivots, or just make a small cover from a plastic bag

I suppose everyone’s anatomy and sweat glands are different, but with proper—even modestly haphazard—-care, I don’t see how this is possible. Are you using a fan to keep you cool and from pouring sweat? Are you wearing a jersey or some type of shirt when you’re riding indoors to absorb sweat?

If you sweat a lot, I suppose wiping down the bike and various component with a wet washcloth or rag would help.

Yes, I stripped the shifter and replaced the cable. I can feel the stiffness in the derailleur when moving it manually. Sometimes it gets so bad that the spring won’t even pull it back down to the lower ring.

I’ve pulled the derailleur off and cleaned it as best I could, but I can’t get directly at most of the moving parts because I can’t get the pins out of the hinges. It appears to be non-serviceable at those key spots.

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I use WD-40 and work it for a few days and continue to douse it. Ideally you can pull it and soak it in a bin, but I don’t bother. It’ll eventually loosen up. I need to get crud off, the spring, however, I can’t quite reach in there, but do spray it heavily and drip it onto some towels repeatedly.

BTW, WD-40 the chain too, wipe it, let it dry, and then lube it. It gets all the crud off of that too as there are cleaners in WD-40.

I’ve thought about a bike thong, but since I’m on rollers I thought it might interfere with steering. I’ll take another look.