Abhi@Singhvi

Hey Folks,

Just picked up a MTB & while riding in gears 4/5 on the lower derailleur there is a constant tick tick tick sound, it is not present in gear 6/7 at all.
Observed and it is like 3 times per pedal revolution & very constant harmonic sound.
Checked the cassette and nothing wrong there.
The gear shifting in general is no problem both in the rear and front derailleur.
Any pointers on where to look in the drivetrain?
I've a video but not sure how to upload it here.
TIA friends.

Retro Grouch 

"Three times per pedal revolution" makes me think it has to do with your rear wheel. I'd put your bike on a work stand or hang it up off the ground and examine the rear wheel closely to see if it's hitting something.

Litespud

I used to hear an audible pinging from my rear wheel (road bike) when in very low gear (small ring, largest 2-3 sprockets) - the noise wasn't audible in higher gears- possibly because wind noise at higher speeds drowned it out, or, if the sound was spokes loading/unloading as the rear wheel revolved, the wheel speed had to be sufficiently low for the spokes to actually load/unload - something they didn't get the chance to do completely if the wheel was spinning faster. Only other thing I can think of if some gears seem a little rough and others don't is a chainline issue? Is the chain deflection more extreme with the noisy gears than with the quiet ones?

Abhi@Singhvi

Thanks and appreciate the quick response -
I will examine the rear wheel & spokes again.
The noise is strong enough tok tok tok kind of noise, i've observed closely and it goes away when riding in higher gears (lowest size cassette on the rear derailleur).
i am trying to see how to share a 10sec video clip here.

Abhi@Singhvi

Thanks
The chain deflection if I understand correctly would be the angle of chain between front and rear derailleur? if yes than it's not that bad in the gears when the noise is heard.
I will check the rear wheel and examine the spokes also.
What could be a possible chainline issue, any pointers?
I've had this bike since past 10 days and just did 1 trail ride and few road trips with it.
Thanks

Litespud

If the bike is new, then it could simply be that your rear derailleur is moving out of adjustment as the RD cable stretches. This is completely normal - a characteristic of a cable-operated system rather than a fault, and one that is easily adjusted out. Many/most shops offer a free 30-day tune-up just to cover things like this. Depending on the system, this might manifest itself more in some gears than others. If I was in your shoes (and I had a bike stand or some way of suspending the bike), I might put the bike through its gears while looking at how the RD is aligning with the sprocket at each gear setting. If the top jockey wheel is not exactly in line with the chosen sprocket when viewed from the rear of the bike, then you can tweak it using the RD cable barrel adjuster - there are any number of YouTubes addressing RD adjustment. If this isn't your bag, take it to the shop and have them look at it - an RD tweak is a 5 minute job.

Abhi@Singhvi

Thanks will do, looking for a bike repair stand & will get my hands on it.. i prefer doing it myself and learn rather than let the bike guy enjoy the fun and learning process

Wanderer

Make sure your chain is correct, and not rubbing on any metal - at all!

BobbyG

Post video to youtube or some other streaming service, then post the link here.

It will look like this when you are writing your post:

BUt look like this after you've posted it:

subgrade

Might also be a sign of a slightly bent derailleur hanger.

Another thought - chain can make some noise on less used cogs; the frequently used cogs would be worn down a bit together with the chain, while the less used are still like new and don't mesh perfectly with a slightly worn chain anymore. That kind of wear can be invisible to the eye. However, it's usually the smallest and largest cogs that see less use than the middle of the cassette, but it might vary with gearing, preferred cadence, terrain etc.

Danno85

I had a similar tic tic tic happening to me and it only happened in a couple gears and seemed to be when I was really cranking on the pedals. I kept readjusting everything and lubed everything I could think of and it drove me nuts. Then on a whim I removed the reflectors from the wheel spokes and that solved it. I couldn’t believe it. Mine was on a Trek FX3.

Wanderer

Make sure your chain is routed correctly around the rear derailleur. I have seen more than one routed wrong, even from a bike store! It should NEVER run over anything but jockey wheels and the rear cassette.