Clattering coming from new CX2020 motor

[Pylie1]

Hey guys,

What is the rattling/clattering noise in the new CX2020 Bosh motor??
It makes a hellava rattle whilst the motor is disengaged over rough terrain.

Is there a fix to quieten it down as yet?

I’m about to buy a new Orbea Wild FS and whilst the bike is awesome, I’m not sure if I could put up with the rattling long term! The majority of my riding is rough, rocky downhill tracks so I’d be listening to it constantly.

Any input would be much appreciated!

 

[Gazzaaitken]

I have a wild fs, and mine is quiet, I've not noticed any rattling, I was actually thinking about how quiet it was after a day at Glentress

 

[Rob Rides EMTB]

Hey guys,

What is the rattling/clattering noise in the new CX2020 Bosh motor??
It makes a hellava rattle whilst the motor is disengaged over rough terrain.

Is there a fix to quieten it down as yet?

I’m about to buy a new Orbea Wild FS and whilst the bike is awesome, I’m not sure if I could put up with the rattling long term! The majority of my riding is rough, rocky downhill tracks so I’d be listening to it constantly.

Any input would be much appreciated!

It’s happened to all of the 2020 Bosch motors I’ve tested. Only really noticeable on very rough rocky fast stuff. But it’s there. It’s when the motor is not fully engaged and you have pedals level. It’s like there’s some kinda movement in it.
2 bike companies I spoke with also acknowledged it.

Some bikes sounded worse than others. Cube stereo Hybrid 140 was the loudest. Mondraker crafty RR the quietest.

 

[Pylie1]

2 bike companies I spoke with also acknowledged it.

Thanks for the reply Rob. When you tested the Orbea Wild FS, would you say it's quite noticeable?

I have a wild fs, and mine is quiet, I've not noticed any rattling, I was actually thinking about how quiet it was after a day at Glentress

Thanks for responding. Apparently, it sounds a little like chain slap?

 

[Rob Rides EMTB]

Thanks for the reply Rob. When you tested the Orbea Wild FS, would you say it's quite noticeable?


Thanks for responding. Apparently, it sounds a little like chain slap?

Not really. I could honestly only notice it over constant rocks. Although my mate Adam who’s since been riding the Orbea has heard it.

 

[WilkyWay]

My Rail 7 is the same. Although it’s only noticeable on one trail at my local trail centre, which is called boneshaker funnily enough. It’s all fairly quick, very rooty and no pedalling which is what everyone is describing as the situation where they can hear the clattering noise.

 

[Pylie1]

My Rail 7 is the same. Although it’s only noticeable on one trail at my local trail centre, which is called boneshaker funnily enough. It’s all fairly quick, very rooty and no pedalling which is what everyone is describing as the situation where they can hear the clattering noise.

Would you say it’s loud? Or is it a little like light chain slap?

What do you think of the new motor mate?

I’m thinking, bite the bullet, buy the bike and see how it goes. If it’s super noisy, surely there’s has to be some form of work around.

I just so don’t want to head down my Favorite downhill track and have to listen to metallic rattling all the way down! So frustrating having to buy a bike without being able to ride it. You have to go on internet opinions only... which is way better than a stab in the dark I might add.

You would also hope Bosch work out some form of mod, with so many bikes this year with their new motor.

Not really. I could honestly only notice it over constant rocks. Although my mate Adam who’s since been riding the Orbea has heard it.

Thanks Rob?

 

[WilkyWay]

Would you say it’s loud? Or is it a little like light chain slap?

What do you think of the new motor mate?

I’m thinking, bite the bullet, buy the bike and see how it goes. If it’s super noisy, surely there’s has to be some form of work around.

I just so don’t want to head down my Favorite downhill track and have to listen to metallic rattling all the way down! So frustrating having to buy a bike without being able to ride it. You have to go on internet opinions only... which is way better than a stab in the dark I might add.

You would also hope Bosch work out some form of mod, with so many bikes this year with their new motor.



Thanks Rob?

It's loud enough for you to notice definitely. I would say louder than chain slap. I hate constant rattles on my bikes but where I ride it doesn't do it often enough for me to be too bothered. I think I have some GoPro footage of my first ride out that I can dig out to see how audible it is if you like?

As for the bike itself, I love it. It took a few rides to get the best out of the heavier bike but I constantly want to ride it.
The motor itself is very good. It's nice and quiet and EMTB mode is brillant for trail riding. The only negative thing I would say about it is if you are riding above 15mph a lot, specially sprinting down a trail it's noticeably harder to pedal than a none ebike, but that's obviously not bike specific and probably depends how strong your legs are.

Is there a Trek dealer nearby that could give you a demo?

 

[Pylie1]

Is there a Trek dealer nearby that could give you a demo?

Thanks for the offer of the audio? There is a Trek dealer an hour away from me actually! I’m going to give them a buzz tomorrow morning and see if there’s one to demo. I’m guessing a few gutter bounces should produce the noise. I’ll post tomorrow night(here in Aus) as to what I find. I’m hoping it’s not too bad and I can order the Orbea sooner than later. Delivery on the bike is the month of May at this stage. Thinking if it’s a no go, the next option is the new Merida.

 

[Bomble]

I demo’d an Orbea and it had the loud rattling over rough fast tracks, it did put me off the bike a bit.

 

[Pylie1]

I demo’d an Orbea and it had the loud rattling over rough fast tracks, it did put me off the bike a bit.

Hmmm that’s exactly what I’m afraid of. It’s a lot of money for a bike and listen to metallic banging all the way down the trail.

Where as the Merida is apparently one of the quieter bikes. The high front end puts me off a bit as I was thinking of a 170mm fork on the front. It’s so hard to buy a new bike nowadays ?

What bike did you end up buying?

 

[EMTB Rider]

I have a USA spec Rail 9.7 and all I ride is rocky ruff trails and my bike does not make any noises. It must be a Euro thing.

 

[Pylie1]

I have a USA spec Rail 9.7 and all I ride is rocky ruff trails and my bike does not make any noises. It must be a Euro thing.

Rob did say that some bikes were worse than others for sure. It could be the way the geo is setup that’s having an impact? I might just have to give up on the Orbea and settle for something else.

 

[Bomble]

Hmmm that’s exactly what I’m afraid of. It’s a lot of money for a bike and listen to metallic banging all the way down the trail.

Where as the Merida is apparently one of the quieter bikes. The high front end puts me off a bit as I was thinking of a 170mm fork on the front. It’s so hard to buy a new bike nowadays ?

What bike did you end up buying?

I demoed a 2020 levo and loved it so bought one. I really liked the Orbea but size large felt to have too small reach and the rattling put me off it.

 

[GrahamPaul]

As the rattle seems to be when the bike is freewheeling so that the clutch is disengaged, would a solution to the problem be to fit Chris King freehubs...?

 

[Pylie1]

As the rattle seems to be when the bike is freewheeling so that the clutch is disengaged, would a solution to the problem be to fit Chris King freehubs...?

Well, I guess that's one way of 'silencing' the noise ??

 

[Pylie1]

I demoed a 2020 levo and loved it so bought one. I really liked the Orbea but size large felt to have too small reach and the rattling put me off it.

Yep, I don't think I'll worry out the Orbea now. Just seems to be too many negatives at the moment. I want to support my LBS so my choices are only Orbea, Merida or Rocky Mountain. Sounds like the Rocky Mountain motor is way noisier than the rest by all reports. I was pretty keen to try the new Bosch motor... looks like it's not going to happen.

 

[Pendo]

Yep, I don't think I'll worry out the Orbea now. Just seems to be too many negatives at the moment. I want to support my LBS so my choices are only Orbea, Merida or Rocky Mountain. Sounds like the Rocky Mountain motor is way noisier than the rest by all reports. I was pretty keen to try the new Bosch motor... looks like it's not going to happen.

The 2020 Rocky Mountains are fairly quiet, think they did a mod to the chain guide.

 

[Pylie1]

The 2020 Rocky Mountains are fairly quiet, think they did a mod to the chain guide.

My LBS's getting a couple of demo bikes in next month so hopefully, I'll be able to give one a try before I buy. I was ready to put down a deposit this week... now I'm thinking hold off for a couple of weeks and see what develops. Still hoping Bosch will address the noise in the motor...

 

[Rusty]

When out playing today there was a guy who asked me about a noise he was hearing. Took the bike for a short ride down a rock-garden and heard it. Pretty certain the noise was the wiring loom slapping against the down-tube - at least that was my impression.
Had one of the first Giant 29er hardtails and the internal cable for the dropper used to rattle around and annoy me so badly that I removed it and went to a conventional seat post. As it was a XC racer I never used the dropper anyways. The sound I was hearing today was reminiscent of that ... but a lot quieter.

 

[Akiwi]

Tell you the truth, I haven't noticed the noise yet on my new 2020 Cube. But It's winter, and the trails are mostly soft here, so it might be that I haven't been in the right situation yet. Also only done about 80 KM.

 

[GrahamPaul]

I have noticed the noise on my new (less than one week old) Focus Jam². Before I'd read Rob's posting I had actually got off the bike to check that the derailleur clutch was engaged because it did sound like a light chain slap. The clutch was engaged so I then thought it would probably be cables rattling around internally - reminiscent of my hamster bike when a cable was a bit loose and rattling against the frame.

Anyhow, after reading Rob's posting I took it out on one of the donkey tracks yesterday. These made up with large, round cobbles on the side of steep hills and were access to the village before cars. I can get the bike to rattle hitting these at speed. On the less steep bits I could pedal enough to engage the motor clutch. The rattle stopped. Stopping pedaling, the rattle started again. It has to be the motor clutch rattling.

How much is it going to annoy me? I don't know. This is Spain, so all downhills are rough, rocky and chunky. I'm going to be hearing that rattling a fair bit... maybe. Usually I'm too busy trying too stay alive to worry to much about such things. Time will tell.

 

[Pylie1]

How much is it going to annoy me? I don't know. This is Spain, so all downhills are rough, rocky and chunky. I'm going to be hearing that rattling a fair bit... maybe. Usually I'm too busy trying too stay alive to worry to much about such things. Time will tell.

Yep, I'm thinking on the fast downhill sections you're mind would be on other things! I'd be a little the same. When you get a little breather and pump through a section... that could be a problem. I hate it when I hear cables rattling or a slight bottom bracket creak. It spoils the ride for me and the money is quite high for these types of bikes, and to hear constant clattering... I feel it's not good enough. A lot of reviewers don't even mention the noise on a particular bike, then you have one that picks up on the noise and it irritates them. One reviewer wrote, " A great bike that ticks all the boxes... if you can put up with the noise". This is just a random bike with the new CX 2020 Bosch motor in it.

 

[Beezerk]

Tell you the truth, I haven't noticed the noise yet on my new 2020 Cube. But It's winter, and the trails are mostly soft here, so it might be that I haven't been in the right situation yet. Also only done about 80 KM.

Same with my Whyte, then again I am a bit if a pussy when it comes to the rough stuff

 

[Mingui]

Hola chicos

 

[Mabman]

Buying into 1st year equipment, especially mechanical or electronic, is never a good idea but always seems to be appealing.

As much testing as I am sure Bosch went through before releasing the Gen 4 motors sometimes faults can only present themselves via getting numbers of them out there and how those numbers were created via manufacturing that may be on a small sliding scale like the old don't buy a car made on a Friday.

 

[Rob Rides EMTB]

Bosch Gen 4 Motor Noise - EMTB Forums

And I talk about it at about 5:55 in this video. You can also hear the noise...

 

[Akiwi]

Aaaargh.. I just listened to Robs video again and realized that I do have that noise. I thought it was the cables that I had put in for my lights. Was going to try to re route them or add some dampening in the head tube area... but now I realize it is probably that horrible motor noise.
Grrrrr!

 

[Bearing Man]

I have just finished stripping and inspecting the new Bosch Gen 4 motor and may have a theory for the clattering noise.
You will see in the photo the 2020 Gen 4's crankshaft with the sprocket carrier over the outside. 3/4 of the way down the crankshaft is a black "cage" inside is a freewheel mechanism that consists of two fine tooth ratchet faces pressed together by a spring as shown in pic 2.
If the ratchet lifted to the top of the teeth and was then slammed back into the stops of the teeth hard enough, it would "clack". This maybe happening as the bike is violently moving up and down from both ends while the crank is stationary?

 

[Loamranger]

Great post PLB. Can you see a fix?