utoner34

Ok, sometimes very randomly, I get load chain "snap" noise (dont know how to better describe this, like the chain snaps into its place finally) after (I think rear) gear change.

It may happen few seconds after gear change or sometimes even minute or so. No chain skipping, nothing like that, just the noise.

The bike is new, and I have already done ~1000km on it.

I checked everything, all is tight, including cassette. Bike shifts perfectly. Chain is clean, lubed etc..

Again, noise happens occasionally and not often. (although on my last 200km ride it did happen 10 times or so and its annoying)

But I had this sound (again very randomy and occasionally on some of my previous bikes)

Cant realy say if it happens in any particaul cog but it doesnt matter because the bike is new.

I wish I had the sound filmed becuase I am sure you would recognise this immediatelly.

I have cleaned the chain from annoying factory sticking grease and use my own lube as usual.

Iride01 

I get that too on new bikes. I think all the sharp edges just catch the chain randomly and don't let it drop in place properly. It'll wear in and be better with time. Though several things seem to help. Make sure you shift before your cadence gets too low. If you are <60 rpm it's too low already IMO. You probably are having to put more power into the cranks than you should be during the shift. If you do have to shift at low rpm, then try to soft pedal and don't stop till you've made a full revolution of the crank, sometime more.

If you are coming up on a hill, plan to keep your cadence up. So shift before it slows. Many times my cadence going up hills is 90 rpm, which is 10 rpm faster than what I cruise at. Makes hill climbing a breeze when you use the lower ratio gears instead of brunt leg muscle force.

The bike is still new? Here where I'm at the bike shops will always be willing to look at a bike they sold and tell you if it needs anything. Even a year or two later.

Duragrouch

Ping noise: Well obviously you are lugging in too high a gear and the higher peak pressures and/or too low a fuel octane is causing preignition, the pinging is the cylinder walls vibrating.

My work is done here.

Bill Kapaun

What type of gear train? 1X, 2X, 3X?
Are you easing up pressure when you shift?
Monster sized cogs like an 11-40 or worse?

The shift wire may have "worn in" a bit.
Try turning the barrel adjuster on the RDER CCW 1 click & test.
KEEP TRACK of clicks.
If this improves or no change, add 1 more click & repeat.
At this point, things should get bad or better. If bad, go back to zero and try the other direction.

zandoval 

10° Before Top Dead Center is a start.

As to the OP: Be sure to check the cogs on your Freewheel/Cassette. Remove the wheel then check each cog by grabbing it and rocking it back and forth. On a freewheel ya get a Cluck. Rats I hate clocks and pings, especially if I dont know where they come from...

utoner34

Tiagra
11-34 , 50-34

Yes, I do ease shifts, but its not always milk and butter when you are training hard.


Didnt quite get what should I check about cogs? They are clean.

zandoval 

I don't know if you are using a Freewheel or Cassettes. I will describe a problem I had with Freewheels. I do most of my ridding in the third cog on my Freewheel. With one wheel set I would get a inconsistent cluck every now and then when in that gear. I finally found, by exchanging wheel sets that the cluck was coming from the Freewheel. I replaced the clucking Freewheel and the cluck disappeared. Latter I did a close examination of the Freewheel and noticed that the third cog would rock back and forth slightly. I then took the Freewheel apart, cleaned it, put it back together and rats. It still rocked back and forth and clucked. The remnants of that Freewheel now make up a nice wind chime hanging in a tree.

So what was it? I dont know. It could be shims and spacers on the ChiCom Shimano Freewheel. Or even eccentric wear on the hub. What ever the case I have come to find that Freewheels are very much like Chains. You replace them when they are worn or start giving you problems.

If you can, switch out the wheel set and see if your problem persists. If it does not then its not the Wheel set giving ya problems.

Hope this helps...

utoner34

I use cassette

masi61

If you are using a quick link I think it could be responsible. The Wippermann Connex ones I use I think have some accumulated misalignment and once or twice a ride it will auto-realign with a clunk. What brand of chain are you running and what type of quick link is on it?

Iride01 

So did you ever go back to the shop you bought it at and ask them? Was it bought at a bike shop or a big box discount store that doesn't have a bike mechanic?

Still I think the likely issue is that you are shifting at too low a rpm and with too much force on the pedals. If you can say that you are shifting at 60 rpm or above then there is less chance of that being the issue. But even at 60 rpm, you have to be a little lighter on the pedals as you shift. At greater than 70 RPM, you probably are in a easy enough gear that you don't have to lighten up much if any at all.

But there are other things it could well be. If the chain is original to the bike and was put on at the shop, then I think the quick link suggestion might just be a red herring. But still worth a check. But how would you know if it's correct or not?

Another more real possibility is that the DR hanger got bent from the bike falling over or getting banged while loading in the vehicle whether in a trunk or on a bike rack. Or just simply that the barrel adjuster needs a few turns to line the jockey wheel up with the rear sprocket it's supposed to be on.

soyabean

Check each link roller pin, one of them can be sheering off.

Happened to me just a few days ago on my winter beater, chain is rusted of course, but was still stretching good between 0.50-0.75 .