Captain_Canada

Hello!

I've got a creak that's driving me nuts on my 2021 Giant TCR with Ultegra (latest version).It sounds like it is coming from the cassette and creaks on both L and R strokes of the pedals.

It kind of sounds like a chain rubbing against front derailleur but it is not that/the chain isn't hitting anything (there is a grinding sound, I can feel a vibration when it happens through the bike, pedals, and handlebar, I think sound is coming from the cassette. The noise seems worse when towards the top of the cassette (bigger sprockets). The creak still happens when riding no handed (I don't think it is the headset). The noise sounds like rat rat rat, rat rat rat.

Things I have tried so far that have not worked: thorough cleaning, degreasing/relubing the chain, changing the chain, re-greasing the pedal threads and torqueing to spec, cleaning/reapplying carbon fiber paste to the seatpost, checking that chainring bolts are tight, greasing the through axels, checking that headset is torqued right, cleat bolts are torqued correctly (SPD-SL), the cassette is torqued to spec.

The noise is worst when climbing. Noise does not increase much with force (at 170+ it starts-according to my power meter, but does not get louder as I put more power out after that). I can get the noise to happen in the big or little ring, but it seems worse in the little ring (maybe because I'm climbing in the little ring).

The noise is not as bad when out of the saddle but I can get it to make the noise still.

I can get the noise to happen in the big or little ring. When I'm further up the chainring (bigger sprockets) it happens. It does not happen when going hard in the big ring on the flats (when in a smaller sprocket on the cassette).

I can’t feel any play in the bottom bracket when grabbing the cranks but I don't really know what I'm doing.

The only issue i've had with the bike so far: the freehub (Giant/DT Swiss) at one point spun backwards and forwards due to too much grease in it (factory put too much in). My local bike shop removed some of the grease and it started working normally after that. Then about 500 miles later this started to happen. I don't know if hubs would make that type of sound though. My next idea is to take apart the hub/service that.
Any advice on the next thing I should do?

Thank you!

Bodgeitbob

Chain/cassette tension?

Captain_Canada

Hi Bodgeitbob can you explain what you mean by chain/cassette tension? Thanks!

Andrew R Stewart 

How many different types of sounds are you chasing? "I've got a creak" "It kind of sounds like a chain rubbing against front derailleur" " I can feel a vibration when it happens through the bike" "The noise sounds like rat rat rat, rat rat rat"

I do wonder if you're mixing different things though. The vibration could well be common chain on cog tooth, especially as you either run smaller rear cogs or crossing chain angles. What frequency is the "rat rat, rat..."? Rhythmic with cadence, wheels, other? Andy

thook

spoke tension?

Captain_Canada

Andrew R Stewart it is all the same noise. It coincides with pedaling, does not do it every time but when it starts on a climb it keeps going. It sounds like something is moving or rubbing-kind of like the chain is rubbing on something but it isn't. Cleaning the chain or lubing the chain or changing the chain entirely doesn't make it go away. It's driving me nuts. I hear it more when I'm in the bigger sprockets (so typically I'm in the small chainring when this is happening/climbing).

It doesn't seem to be related to how hard I'm pedaling. It starts at about 170 watts but doesn't get louder as I go harder. If I'm really hammering on the flats in the big ring/small cassette sprocket it doesn't do it (no noise).

I think I've tried everything other than: 1. pulling the bottom bracket (since it doesn't get worse with more power I don't think it is that, but I'm not sure, and I don't have the tool to do it) and 2. removing the chainring bolts and relubing (though I have checked the torque on them and they're fine).

I haven't done anything with spokes or hubs either since the noise started. I did have a recent problem with my hub (spun freely forward and back due to too much grease) and am wondering if the bike shop removing grease so the pawls would re-engage might have been overkill. The noise seems to be worse in good/hot weather.

The drivetrain has about 3k miles on it, chain is brand new (100 miles) since I tried changing it to get rid of the noise.

Iride01 

A creak and a chain rubbing aren't the same sound to me either. A chain rubbing is usually a chain rubbing. I've never heard anything else make a sound like a chain rubbing something.

If this is a creak that you think occurs when you push on the left and right pedal and it seems to be coming from the rear hub, then I'd first suspect the spokes on the rear wheel rubbing with each increase and decrease of power to the rear. So maybe have the wheel spoke tensions checked by someone that knows how to properly adjust and tension them.

Captain_Canada

UPDATE: it was the freehub/servicing it got rid of the creak. About 500 miles ago the freehub was spinning backwards and forwards due to too much grease packed in by the factory. My bike shop had taken out a bunch of the grease at that point, and then the noise and vibration started a couple months later. I got it serviced this week and now it feels great and runs silent.

The freehub I think is a DT swiss whitelabel (in Giant SLR1 wheels). I'm going to service it myself the next time. Posting here in case anyone arrives via google in the future. The sound at its worst was kind of like the noisy hinges on a very heavy old door (the sound evolved and loudened as I put more miles on the unserviced freehub).