Bosch CX click?

RustyMTB

E*POWAH Elite World Champion
Jul 22, 2020
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Been chasing a clicking noise on the bike. So far, I've been through the frame bearings, headset, rear shock mounts & seatpost, disassembled & serviced. Through a process of elimination, I've narrowed it down to somewhere around the motor. It's a clicking sound & rotational. Before I fire up the @Bearing Man anyone else experienced similar? Just to help rule out any other possibilities - cranks, lockring, pedals etc.
 

Bearing Man

Ebike Motor Centre
Patreon
Sep 29, 2018
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2,331
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Been chasing a clicking noise on the bike. So far, I've been through the frame bearings, headset, rear shock mounts & seatpost, disassembled & serviced. Through a process of elimination, I've narrowed it down to somewhere around the motor. It's a clicking sound & rotational. Before I fire up the @Bearing Man anyone else experienced similar? Just to help rule out any other possibilities - cranks, lockring, pedals etc.
Too late, already fired up! How many clicks per revolution of the crank? Does it get louder when under power? Does it go away when the motor is off? Does it go away if you stand up and pedal?
 

RustyMTB

E*POWAH Elite World Champion
Jul 22, 2020
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Too late, already fired up! How many clicks per revolution of the crank? Does it get louder when under power? Does it go away when the motor is off? Does it go away if you stand up and pedal?
I knew you'd be awkward! 😂 I'll have to test ride it today to work out the specifics, I've spent the last week convinced it was the dropper!

I can say it doesn't increase in volume no matter how much effort goes through the pedals. The rest I'll work out today.
 

Bearing Man

Ebike Motor Centre
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Sep 29, 2018
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I knew you'd be awkward! 😂 I'll have to test ride it today to work out the specifics, I've spent the last week convinced it was the dropper!

I can say it doesn't increase in volume no matter how much effort goes through the pedals. The rest I'll work out today.
Standing up will rule out the dropper. It usually goes in this order:
Motor bolts.
Chainring bolts (if spider is fitted).
Crank arms.
Pedals.
Suspension linkage.
Rear axle.
Cracked frame.
Headstock. (Yes, most noises travel down the frame tubes and emanate from the motor area).
A good way of diagnosing where sound is coming from, is to find an open area and ride with your head turned to the side (Either side). Once your ears are pointing to the front and rear of the bike, you can normally differentiate better where the noise is coming from. Do not do this in the street or you will ride into the back of your neighbours car! :)
 

RustyMTB

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Jul 22, 2020
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Okey dokey, I'll go for a ride & work through some of the possibilities. I can say with the chain off & the motor switched off, it cranks by hand smoothly & silently although I recognise that isn't partcularly under load and I can rule out the chain ring - direct mount and the seatpot, I actually rode it with the seatpost removed altogether & it was still there.
 

RustyMTB

E*POWAH Elite World Champion
Jul 22, 2020
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I think you can stand down @Bearing Man (for now!) Been for a ride & the clicking is definitely related to pedaling. It happens motor on or off but while it happens rhythmically when I pedal, I've discovered I can recreate it by bouncing on the pedals when freewheeling, which would appear to likely rule out the motor. Also checked motor bolts, lockring & cranks & they're all nipped up good, so now, I'm thinking either frame bearings (again) or pedals or possibly rear axle. Also checked & lubed the mech clutch, so not that but pedaling will cause the rear triangle to compress, hence why I associated it with the motor. All I know is it's driving me mad!
 

RustyMTB

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Jul 22, 2020
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After all that, it turned out to be...

The bloody Nukeproof seatclamp bolt. Not the clamp but the bolt! I've been turned into the kind of obsessive who removes individual bolts to find a creak!!

_6suqa8n.jpg
 

InRustWeTrust

E*POWAH Master
Mar 9, 2020
524
758
Sweden
My Bosch cx 2018 sometimes gives a clicking noise when the wheel is rolling without traction, I think it's the machine. The engine works flawlessly

Hmm that sounds wierd that the engine clicks when you free-wheel, but if your engine works i guess it doest matter so ride on👍😎
 

RustyMTB

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Jul 22, 2020
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The motor is still when freewheeling, or at least it should be if there's no fault or your freehub isn't borked. What you do get with Bosch gen 4's is backlash from the gears which your feet bobbing about on the pedals will transmit through to the motor. It's one of the irritations with them but you tend to tune it out.
 

RustyMTB

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Jul 22, 2020
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OK I'm back with my tail between my legs. The click is back & I can't for the life of me find it. Here's what I've done so far:

Disassembled the headset, cleaned & lubed.
Disassembled the seatpost, cleaned & lubed
Same for the mech and mech clutch.
Removed rear shock, cycled the linkages. Removed & cleaned linkages & can feel one slightly gritty bearing but not terrible.
Changed the saddle.
Ridden the bike with the seatpost out
Removed the motor, ridden it like a balance bike
Swapped the seat post clamp.
Bolt checked the entire bike
Checked pads for rattling,
Swapped the pedals
Lubed both axles
Removed battery & rode bike. Checked cables through downtube to battery & dropper.
Checked frame, definitely not cracked.

I'm at a loss where to go from here. 747's aren't serviced this hard. All contributions welcome.
 

Tepi

Member
Nov 18, 2018
71
33
Finland
OK, olen takaisin häntäni jalkojeni välissä. Napsautus on palannut, enkä löydä sitä hengissäni. Tässä on mitä olen tehnyt tähän mennessä:

Kuulokkeet purettu, puhdistettu ja voideltu.
Satulatolppa purettu, puhdistettu ja voideltu
Sama mekaanissa ja mech-kytkimessä.
Poistettu takaiskunvaimennin, pyöritetty vivusto. Irrotettu ja puhdistettu nivelet ja voi tuntua hieman rakeiselta laakerilta, mutta ei kauhealta.
Satula vaihdettu.
Aja pyörällä satulatolppa ulos
Irrotettu moottori, ajettu sillä kuin tasapainopyörällä
Satulatolppakiinnike vaihdettu.
Bolt tarkasti koko pyörän
Tarkistettu tyynyjen kolina,
Vaihdettiin polkimet
Molemmat akselit voideltu
Irrotettu akku ja ajettu pyörällä. Tarkista kaapelit alaputken kautta akkuun ja tiputin.
Tarkastettu runko, ei todellakaan murtunut.

Olen epävarma, minne mennä täältä. 747-autoja ei huolleta näin vaikeasti. Kaikki panokset tervetulleita.
Rakeinen nivel laakeri antaa äänen , iskunvaimentimen paineen alaisena.Ilman kuormaa laakeri ei ääntele. Vaihda ne laakerit,uskon vahvasti häiriön poistuvan.
 

Bearing Man

Ebike Motor Centre
Patreon
Sep 29, 2018
975
2,331
UK
OK I'm back with my tail between my legs. The click is back & I can't for the life of me find it. Here's what I've done so far:

Disassembled the headset, cleaned & lubed.
Disassembled the seatpost, cleaned & lubed
Same for the mech and mech clutch.
Removed rear shock, cycled the linkages. Removed & cleaned linkages & can feel one slightly gritty bearing but not terrible.
Changed the saddle.
Ridden the bike with the seatpost out
Removed the motor, ridden it like a balance bike
Swapped the seat post clamp.
Bolt checked the entire bike
Checked pads for rattling,
Swapped the pedals
Lubed both axles
Removed battery & rode bike. Checked cables through downtube to battery & dropper.
Checked frame, definitely not cracked.

I'm at a loss where to go from here. 747's aren't serviced this hard. All contributions welcome.
You did not mention the obvious and most common... motor bolts, chainring to spider fasteners, spider to motor tightness and greased?
 

RustyMTB

E*POWAH Elite World Champion
Jul 22, 2020
2,849
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You did not mention the obvious and most common... motor bolts, chainring to spider fasteners, spider to motor tightness and greased?
I took the motor out of the frame, so know it isn't any of those. Since posting, I've cleaned out & relubed all the pivot bearings & ordered a new set. Definitely sounds back end but sounds are deceptive. Worst creak since my knees turned 50.
 

RustyMTB

E*POWAH Elite World Champion
Jul 22, 2020
2,849
6,892
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Betting the farm on frame bearings now per Tepi's advice above. There is literally nothing else to check - did do spokes & the fork CSU as well as cassette & rear hub. My bike is truly hand built.
 

Bearing Man

Ebike Motor Centre
Patreon
Sep 29, 2018
975
2,331
UK
I took the motor out of the frame, so know it isn't any of those. Since posting, I've cleaned out & relubed all the pivot bearings & ordered a new set. Definitely sounds back end but sounds are deceptive. Worst creak since my knees turned 50.
So it's a creak, not a click? A click can come from a lot of different areas to a creak, only seat posts, motor bolts, crank arms, spiders, chainrings, headstocks, suspension linkages and shocks, all else clicks and you can pretty much rule out.

Did you try the turning your head to the side and listening trick?
 

RustyMTB

E*POWAH Elite World Champion
Jul 22, 2020
2,849
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Yes but that only gets me to the rear end & I'm not certain that's all that reliable. The common denominator is the rear triangle I reckon. I can separate backlash in the motor and a creak the mech clutch makes as the suspension compresses, so literally all that remains are the frame bearings. TBF the bike has done 2500 miles, so it's hung in there but seems now is the time to renew things.
 

Bearing Man

Ebike Motor Centre
Patreon
Sep 29, 2018
975
2,331
UK
Yes but that only gets me to the rear end & I'm not certain that's all that reliable. The common denominator is the rear triangle I reckon. I can separate backlash in the motor and a creak the mech clutch makes as the suspension compresses, so literally all that remains are the frame bearings. TBF the bike has done 2500 miles, so it's hung in there but seems now is the time to renew things.
Sounds like you're getting there 👍
 

Ken

Member
May 30, 2020
53
24
Northumberland
Sounds clicky more like😂

I'll work it out - grateful for everyones suggestions - more eyes the better imo.
Suffered from the same obsessive clicking for weeks caused by rear maxle not tight enough but I am sure this has been covered in your exhaustive schedule.
Another cyclic click was caused by the fat/thin teeth on the gear jockey wheels not being properly located in the fat/thin chain gaps.
good luck.
 

SuperSpooner

Member
Jul 30, 2020
5
1
UK
Ive just fixed a creaking/clicking noise on my bosch CX.
Mine was under load though so knew it was around the motor.
Sure enough, was a loose motor bolt. torqued up and went away.
 

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