Slight creak Bosch CX on Cube

Aug 22, 2016
94
8
119
UK
#1
Hellio,

Nothing major but keen to try and find the cause...

Cube Race Reaction 500 2018 on left pedel downstroke there is a slight creak (sounds a bit like a barn door that needs oiling) on each revolution.

Have tried tightening all the motor casing external bolts but it's still there.

Has the following characteristics:

- creak like the saloon doors of a western bar (only for a split second sounds a bit like pastic rubbing)
- all external bolts snuggly tightened
- does not creak when power is off (I wondered if it was the pedal but no happening with no power)
- not as bad when light pressure on the cranks (ie more you force the pedels the more the noise)
- does not make any noise when motor delivering high torque (ie on a steep hill on turbo pulling up strongly does not creak)
-bike done approx 500 miles and noise not getting any worse

Other than trip back to dealer anything else I can try or do they all do this?

If any other Cube CX motor folk can let me know if theirs also makes this noice much apprecaited.

Many thanks,
 

GLJoe

Esteemed Pedelecer
May 21, 2017
369
25
UK
#2
Other than trip back to dealer anything else I can try or do they all do this?
,
When you've got it consistently creaking, keep peddling with the same force/cadence, but stand up. If the noise stops, its probably the seatpost.
 
Aug 22, 2016
94
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119
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#3
Really? Will give that a go ... very strange as it's pretty solidly tightened up and running a brooks sadle...
 
Aug 22, 2016
94
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#4
Oh and not doing it with the right pedel stroke which makes me think it's motor/crank related - but thanks for idea much apprecaited for assitance.
 

GLJoe

Esteemed Pedelecer
May 21, 2017
369
25
UK
#5
Really? Will give that a go ... very strange as it's pretty solidly tightened up and running a brooks sadle...
It can be tight but still creak. And it won't have to be the saddle, it will probably be around the seat post clamp.
Mine is sounding exactly as you describe (again!) so I need to take it apart and re-grease the stem. That cures mine anyway. I think I used some anti seize copper compound stuff the last time.
 
D

Deleted member 22539

Guest
#6
I used some anti seize copper compound stuff the last time.
Hi
If you can use an aluminium anti seize grease it would be loads better as you can get what they call galvanic corrosion between copper and aluminium if say water is introduced which is highly likely on a push bike
People use copper grease in automotive applications to where they shouldn’t like the back of brake pads on alloy calipers and alloy wheel spigots on hub faces etc
Also as a bonus aluminium anti seize hangs around a lot longer too
:)
 

Gadfly

Pedelecer
Mar 30, 2018
40
7
Lincolnshire
#7
Your Brooks saddle has me thinking. (I do try not to do this often, I find it so tiring). Have you Proofhided your saddle? When you do, ensure you use a small paintbrush to get it between the leather and saddle frame as far as possible. I cured an intensely irritating creak on my (non ebike) tourer.
 

RobF

Esteemed Pedelecer
Sep 22, 2012
4,442
125
#8
Apr 14, 2017
95
5
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iom
#9
On my Bosch CX there was a small bolt under the plastic cover attaching the motor to frame. It came loose and made a creaking sound.
 
Aug 22, 2016
94
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#10
Hmmm small bolt under the plastic cover - thanks. How does the plastic cover come off (appears to be a skid plate and a few bolts but not sure method of removing the plastic cover).

Thought it might be the pedels but swapped them with others and same thing.

Might it be the plastic lining insert of the battery holder tray? This seems to move about a fair bit but it's a noise that happens on the left pedel stroke when it hits around 9 oclock looking from the side.

Always same location of the pedal stroke but nowhere as bad with no assist (bike off).

Thanks for ideas.
 

soundwave

Esteemed Pedelecer
May 23, 2015
8,460
204
#11
3 main bolts hold the motor on and the plastic case just screws in to each other on the left side.

the bottom flap has 2 bolts at the front and one at the back to remove it.


just remove the hole lot to rule out the plastic bits then look at the motor bolts.
 
Aug 22, 2016
94
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119
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#12
Thanks! Do I need to remove the crank arms to get the plastic off or can the bolts be removed at it comes away in two parts?

In other words does the chainring and crank arms need to come off to remove the plastic casing around a 2018 CX motor on a Cube Race Reaction?

Many thanks
 

soundwave

Esteemed Pedelecer
May 23, 2015
8,460
204
#13
yes cranks need to come off
 
Aug 22, 2016
94
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#14
Thank you - much appreciated.

After a bit of playing around when rotating the cranks to pedel - when it meets resistance (ie when just starting to turn the motor spindle) if you rock it back and forth just pressing/releasing/pressing I can hear some clunking and there is about 1mm of resistance/knocking before it starts to turn the internal motor.

I am not sure if it's some looseness inside the motor internal gearing (worse case) or if the whole motor is slightly pivoting side-to-side where it is bolted to the bike.

I will need to remove the plastic covers and just tighted all the bolts that are easy access as disasembling the motor is not something I wish to do as it's only 3 months old.

Many thanks,
 

soundwave

Esteemed Pedelecer
May 23, 2015
8,460
204
#15
Aug 22, 2016
94
8
119
UK
#16
Many thanks all - think sorted (for time being at least).

Took off plastic covers and tightened motor mounting bolts (that connect motor to frame) as they was a bit of looseness in them all.

If you have the same squeeky symptons then well worth checking (but you will need the spider tool/crank puller to complete).

Thanks again,
 
D

Deleted member 22539

Guest
#17
Many thanks all - think sorted (for time being at least).

Took off plastic covers and tightened motor mounting bolts (that connect motor to frame) as they was a bit of looseness in them all.

If you have the same squeeky symptons then well worth checking (but you will need the spider tool/crank puller to complete).

Thanks again,
Glad you found a solution
Doesn’t say a lot for your dealers PDI thou :(
This is the reason I buy a new bike and always go through every nut and bolt
You shouldn’t have to but there you go
 

EddiePJ

Esteemed Pedelecer
#18
Glad you found a solution
Doesn’t say a lot for your dealers PDI thou :(
This is the reason I buy a new bike and always go through every nut and bolt
You shouldn’t have to but there you go
I do just the same. For me it is a way of ironing out any future issues, by learning any peculiar aspects of a bikes construction. I enjoy the process. :)

A shot that you might appreciate Fogo. My pre first ride check over.



You have reminded me of the bearings though. I had forgotten, so will pop in the shop tomorrow for you. :)
 
D

Deleted member 22539

Guest
#19
Glad you found a solution
Doesn’t say a lot for your dealers PDI thou :(
I do just the same. For me it is a way of ironing out any future issues, by learning any peculiar aspects of a bikes construction. I enjoy the process. :)

A shot that you might appreciate Fogo. My pre first ride check over.



You have reminded me of the bearings though. I had forgotten, so will pop in the shop tomorrow for you. :)
Man after my own heart
And a thumbs up on the bearing cheers
 

zakventis

Finding my (electric) wheels
Aug 28, 2017
18
3
UK - Wales - Monmouth
#20
I'm so glad I found this thread - my Trek with Bosch Performance CX (4,000+ miles/1 year) has been creaking for a while and I was unable to pin it down.

Found this thread, read it, took the cover off, tightened the two 13mm nuts and three T20 screws and...

the creaking has gone! Thank You All!

Out of interest, does anyone know the torque these should be tightened to?
 

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