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huskerdont
06-03-2016, 07:54 AM
Got a replacement rear derailleur since the pulleys squeaked on the old one. I had replaced them once and lubed them a few times, but they would always eventually squeak again, probably because the derailleur was a bit misaligned after a crash.

The good news: I installed the new rear derailleur and it shifts perfectly
The bad news: All the sudden I have a ticking sound where the frequency correlates with speed
The good news: It seems to be unrelated to the derailleur since it happens even when not pedaling

I thought at first it must be something in a tire since it doesn't make the noise on the stand, but a few minutes with a flashlight and a magnifying glass eliminated that. The spokes appear to be fine, and although it doesn't sound like a spoke, I'll probably check them more carefully later. The hub is not loose. Since it doesn't happen on the stand, I assume it's not the cassette.

I like quiet bikes, but I also like mysteries. Eventually the cause will turn up, one way or another.

hozn
06-03-2016, 11:01 AM
I assume the ticking is once per wheel revolution -- hence correlated with speed?

I guess first thought is that you have a spoke magnet hitting something (like the speedometer), though this would probably happen on the stand too.

Also check derailleur cable(s) to make sure nothing was left to long and is hitting a spoke. Less directly related, I had a ticking that was happening with each pedal stroke that I was puzzled over for awhile until I realized my FD cable was touching the crank arm :)

My last suggestion would be to make sure that the valve stem isn't rattling in the wheel. This is probably more realistic with [deep] carbon rims, but is something that seems to really only happen while riding/weighted.

Noises are fun. Good luck!

huskerdont
06-03-2016, 12:11 PM
Yes, once per revolution.

Speedometer magnet was one of the first things I checked since that happens often enough. Also, I'm 90% sure the noise is coming from the back wheel, although sounds are notoriously hard to pinpoint while moving.

Derailleur cable is borderline too short since I was able to reuse the old one, so it can't hit anything.

I hadn't thought of the valve stem and will check that.

Mario20136
06-03-2016, 12:52 PM
It may not be coming from the rear wheel. It sounds like a sticky bottom bracket to me. Before inspecting the bottom bracket I would also check the chain wheel bolts are tight and the bottom bracket bolts have the proper torqued applied. If the noise persist then check the bottom bracket for dirt or you may need an overhaul the bottom bracket to include degreasing and cleaning the bearings and repacking the bearings with lithium grease.

Fyi, I recently replaced my ISIS bottom bracket but did not apply the correct torque the bottom bracket bolts. For the longest time, I couldn't figure out where the ticking noise was coming from. Eventually, I found out through the hard way - the bottom bracket bolts came loose halfway through my commute home. Luckily, another commuter with a 8mm/M25 Allen wrench loaned me the tool and I managed to tighten the bolts just enough to get me home safely.


Yes, once per revolution.

Speedometer magnet was one of the first things I checked since that happens often enough. Also, I'm 90% sure the noise is coming from the back wheel, although sounds are notoriously hard to pinpoint while moving.

Derailleur cable is borderline too short since I was able to reuse the old one, so it can't hit anything.

I hadn't thought of the valve stem and will check that.

huskerdont
06-03-2016, 01:01 PM
It may not be coming from the rear wheel. It sounds like a sticky bottom bracket to me. Before inspecting the bottom bracket I would also check the chain wheel bolts are tight and the bottom bracket bolts have the proper torqued applied. If the noise persist then check the bottom bracket for dirt or you may need an overhaul the bottom bracket to include degreasing and cleaning the bearings and repacking the bearings with lithium grease.

Fyi, I recently replaced my ISIS bottom bracket but did not apply the correct torque the bottom bracket bolts. For the longest time, I couldn't figure out where the ticking noise was coming from. Eventually, I found out through the hard way - the bottom bracket bolts came loose halfway through my commute home. Luckily, another commuter with a 8mm/M25 Allen wrench loaned me the tool and I managed to tighten the bolts just enough to get me home safely.

Still ticks when not pedaling though, so I wouldn't think that'd be it. Still, it doesn't hurt to check everything down there.

Vicegrip
06-03-2016, 01:49 PM
Ticking clicking once per wheel rev when rolling but not pedaling and when pedaling removes drive line and cassette from the mix. Not on stand but while loaded up and not pedaling points to spoke / nipple / hub interplay or hub, bearing and axle or even a crack in the rim. Spray some lube into the axle area and test. Feel each spoke and look at the cross points. Look for cracks in the rim.

Remote chance of something stuck to the tire you have not seen?

hozn
06-03-2016, 01:49 PM
Yeah, I think you can rule out drivetrain -- which is GREAT.

hozn
06-03-2016, 01:52 PM
One other potential: something stuck to the tire (e.g. small rock)? Hopefully not something stuck into the tire! :). That also would only happen on the road.

huskerdont
06-03-2016, 02:13 PM
Tire should be ruled out b/c of previous examination, but crack in the rim seems possible. The sound seems to have changed ever so slightly from the tick-tick of something in the tire to a slightly more creaky sound reminiscent of the last time I cracked one. I'll look it over and likely throw on another wheel for comparison.

DismalScientist
06-03-2016, 02:54 PM
Not all sounds coming from the rear are actually caused by the rear wheel. I had popping noises I thought was coming from the bottom bracket on my fixie. It turned out my front hub had lost most of its grease.

Harry Meatmotor
06-05-2016, 09:17 AM
What kind of rim? Rims with eyelets can crack around the interior of the eyelet - not visible unless you remove the spoke nipple. I've seen quite a few older Mavic Open/Open Pros with full eyelets crack after a bazillion miles. Same symptoms; clicking/tic-toc-ing usually once or twice a wheel revolution. Try taking a rubber mallet, or the rubberized end of something like a pedal wrench and tap the side of the rim. Sometimes a cracked eyelet will make a buzzing noise if you tap the side of the rim. Not much you can do about a cracked eyelet aside from replacing the rim. Nowadays, I typically don't recommend using eyeletted rims - aluminum rims (technically, the extrusion profiles with thicker spoke beds and the harder alloys used these days) have gotten a lot better since the late 80s - early 90s.

huskerdont
06-06-2016, 07:05 AM
What kind of rim? Rims with eyelets can crack around the interior of the eyelet - not visible unless you remove the spoke nipple. I've seen quite a few older Mavic Open/Open Pros with full eyelets crack after a bazillion miles. Same symptoms; clicking/tic-toc-ing usually once or twice a wheel revolution. Try taking a rubber mallet, or the rubberized end of something like a pedal wrench and tap the side of the rim. Sometimes a cracked eyelet will make a buzzing noise if you tap the side of the rim. Not much you can do about a cracked eyelet aside from replacing the rim. Nowadays, I typically don't recommend using eyeletted rims - aluminum rims (technically, the extrusion profiles with thicker spoke beds and the harder alloys used these days) have gotten a lot better since the late 80s - early 90s.

You are spot-on--it is a Mavic Open Pro with Ultegra hub. Amazing.

I had convinced myself it was the hub, even though it's a fairly new wheel, because there was a line of grease along the cap over the hub in the non-drive side. I figured there was nowhere else that grease would come from but within. Took it apart and relubed everything. The grease looked good and there was very little grit inside, probably no grit at all near the bearings. But I'm still getting the ticking (although it's changed to being more episodic, and is less regular, as if it's not once for every revolution now), so unless I'm hearing one of the bearings tick over noisily for some reason, I think you're likely right about the rim eyelets. I'll ride it until it bugs me or gets worse, then throw the old Alexis wheel back on until I find a replacement.

Harry Meatmotor
06-07-2016, 07:44 AM
Another trick you can do to test what's making the noise is to grab the rim/tire and the non-drive chainstay and squeeze the rim towards the chainstay. then repeat with the drive side. Work around the rim, squeezing every spot between the spokes. this will unload both the drive and non-drive spokes enough to get a cracked eyelet to make some noise, usually.

huskerdont
06-07-2016, 07:50 AM
Another trick you can do to test what's making the noise is to grab the rim/tire and the non-drive chainstay and squeeze the rim towards the chainstay. then repeat with the drive side. Work around the rim, squeezing every spot between the spokes. this will unload both the drive and non-drive spokes enough to get a cracked eyelet to make some noise, usually.

Thanks, will do. The wheel is still under warranty so if I can determine for certain, I may use the warranty if I don't opt for a different wheel.

huskerdont
12-14-2016, 12:52 PM
Update: Decided to just ride this until the wheel needed replacing, then put the old one back on. However, the mystery noise went away as soon as the weather got cool. As long as summer never comes back, problem solved! :rolleyes: