I fitted a new chain, and am getting some slight noise when pedalling in the big ring, with some (magnetic, I think) metallic particles coming off the transmission - not good! Chain’s the correct type, length, lubed, no stiff links, threaded through rear mech correctly; jockey wheels and BB seem OK; indexing was correct (Di2 but fiddled with it anyway).
But, the outer chainring looks a bit ropey to me. Could this be the culprit? This is a GRX 11-speed, but used on a road bike, and gets a reasonable amount of cross-chaining in the big ring .
Shift up so the chain is on the big ring. Then look at the way the chain sits in the lower trough of the teeth. If it is “riding high” at one end or the middle, it can be a sign that the ring is excessively worn.
Is this a high mileage chainring and/or have you replaced a chain after the best wear point that might have lead to excessive wear on the ring?
That is some solid mileage then and cross-chain would seem likely to increase wear rate, especially on a 2x system. I’d see what others think, but if you are having issues after the new chain it may well be time for a new ring.
I’ve had a chain jump off of my big ring when I stomped on the pedals to start a sprint. Worn chainring, new chain. Didn’t mix. Went down HARD.
Not fun! It resulted in a hip injury for me, a trip to the hospital, and a broken collarbone for the person who was riding behind me when it happened. Had to take over a month off of training to recover from that crash.
After that happened, I always err on the side of caution and replace drivetrain parts liberally. It’s worth it for the peace of mind!!
For a noise, if you think its coming from the Chainring area I’d look at you chainring bolts first, and only replace the chainring if there was some visible shark toothing and shifting problems.
If these have 14k miles on them (i. e. over 20k km!), in my book they did their job and I’d just replace them. Keep in mind that worn parts of your drivetrain will cause more wear on the chain and other parts.
In my experience, a sure sign of a worn chainring is that you get additional noise with a new chain or even skipping under load. That’s because the old, worn chain will stretch into the worn, stretched grooves of your chain rings’ tooth profiles.
NB I assume the more significant cross-chaining occurs because of the GRX crank offset; compared to a road crankset, you notice cross-chaining sounds a gear or so higher, and the big-big combo sounds pretty ropey (& generally try to avoid)
Regarding the noise, it’s always extremely tricky to pin down where they’re coming from and guesses are often way off, but it sounds like a tinking/pinking/ticking sound, more from the rear. It seemed to begin after the chain swap. Indexing didn’t fix it so I cleaned the chain and noticed the metallic bits coming off on the cloth and then in the chain cleaner, on a chain that’s done just a few hundred miles - never seen silvery flakey bits like this before!
+1
I would think the noise is coming from elsewhere.
The chainring looks worn but not that at you better get a new one right now.
Now, normally I see cassettes wearing a lot faster than chainrings. Have you replaced your cassette? How badly worn was the old chain?
Absolutely. I replace chains frequently to reduce the wear rate on the pricvier/hasslier bits; the cassette has been changed previously, but chainrings are original. I don’t really ride in winter, or in poor conditions, so my stuff doesn’t get hammered and historically has lasted well.
As a person who has broken a few different chains during sprints (and almost crashed) I’m here to tell you it’s not worth it to try to fully maximize mileage on components that wear down over time.
This is a GRX setup with what I suspect is an 11-speed 48t ring. CC doesn’t seem to sell just the ring, but this one shows an option around $100 USD if it’s the right one:
Chain rings seemed a decent stab as the cause (the new chain not liking the old big ring). As I can replace both chainrings for 130 GBP - ie. no big deal - I wondered whether people thought they looked rough enough to warrant it!
PS I have LHS crank PM, so no problems there.
Beyond the chain rings (where the outer clearly has some wear - not terrible, but still), I’m not sure what else to consider, as it all seems OK to my inexpert eye.
I’d consider the bottom bracket as potential source of noise. Service or replace as needed.
Also, lube the seat tube. I know not everyone is fond on that, but since you are not on a carbon frame, that might take care of it.
As a first step I’ve cleaned the chain and heavily re-lubed, and will see if any change. That guy’s solution was to replace his new chain. I’ve also ordered a second chain, an X11-EL, and will try that as step 2. If no joy, and in the coming months regardless, I’ll try replacing the chainrings next. BB seems good but that will probably be step 3.5.
I find new chains (and cassettes and rings) are always a little noisier when first installed before they get worn in a bit. 14k miles is nothing on a big chainring in my experience, I seriously doubt your needs replacing unless it was damaged somehow. I don’t think I’ve ever worn a chainring out prior to ~40k miles and I ride in all kinds of slop and grit.
That chain ring doesn’t look excessively worn and the source of the sound. Have you tried mounting your bike on your turbo but don’t engage the wheel roller? Then turn cranks slowly by hand and try to isolate the sound. Record the sound if you can whilst doing this, and share.
Just a thought but have you threaded the new chain through the derailleur’s properly? You haven’t got the chain running over the metal part of the cages or anything daft like that?
.
