Back gear Squeaking noise

I dunno nothing about bike tech so I pose this question here...
My mountain bike has a Squeaking screeching noise whenever I engaged back gear
3, 2 and 1. Other 4, 5 and 6 gear are all ok. I tried to figure out what caused this noise and not sure where the noise from. My best guess according to my online finding is RD (rear derailed) causing the noise. The chain and RD is not fully engaged whenever the back gear is on from 3 to 1. Am I right or not?

wrote:

I dunno nothing about bike tech so I pose
this question here... My mountain bike has
a Squeaking screeching noise whenever
I engaged back gear 3, 2 and 1. Other 4, 5
and 6 gear are all ok. I tried to figure out
what caused this noise and not sure where the
noise from. My best guess according to my
online finding is RD (rear derailed) causing
the noise. The chain and RD is not fully
engaged whenever the back gear is on from 3
to 1. Am I right or not?

Is there a noise if you hang the bike and pedal
with your hand or is it only when you sit
on it?

For sure, the chain doesn't scratch into
anything obvious along the way?

Does anything look different with 1-3 compared
to 4-6?

Does it get better/worse from 1 to 3 or is it
the same?

--
underground experts united
http://user.it.uu.se/~embe8573

On Thursday, September 21, 2017 at 12:19:08 AM UTC-7, wrote:
I dunno nothing about bike tech so I pose this question here...
My mountain bike has a Squeaking screeching noise whenever I engaged back gear
3, 2 and 1. Other 4, 5 and 6 gear are all ok. I tried to figure out what caused this noise and not sure where the noise from. My best guess according to my online finding is RD (rear derailed) causing the noise. The chain and RD is not fully engaged whenever the back gear is on from 3 to 1. Am I right or not?

Just off-hand it sounds like your derailleur is maladjusted.

On 9/21/2017 2:19 AM, wrote:

I dunno nothing about bike tech so I pose this question here...
My mountain bike has a Squeaking screeching noise whenever I engaged back gear
3, 2 and 1. Other 4, 5 and 6 gear are all ok. I tried to figure out what caused this noise and not sure where the noise from. My best guess according to my online finding is RD (rear derailed) causing the noise. The chain and RD is not fully engaged whenever the back gear is on from 3 to 1. Am I right or not?


I have no idea whether you're right because I can't
understand what you asserted.

Noise from rear end when pedaling:
1. Lubricate chain. If noise persists,
2. Check/ rectify rear changer alignment. If noise persists,
3. Open and lubricate both rear changer idlers.

Noise from rear while shifting:
Snap out a casing from its stop. Withdraw wires from
casings, wipe oil on the orqangey rusty parts or replace
cables and casings.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971