Bosch CX motor maintenance, greasing & what are the holes on the frame?


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2:36 PM
Aug 16, 2020
Hello everyone.
I have Scott e-genius 710 2017 bike with Bosch CX motor and I could not find anything about maintenance of outer parts.
Do I have to lube that exposed part on right side of the motor near the crank set?

And what are those two holes on the frame on-top of the motor? Should I seal those?

Thanks anyone with any info ;)!
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The area you highlighted is known to be a weak point for the bearing. It somehow allows dirt and humidity to enter.

If you ride in wet environment you should clean and grease this once or twice a year.

Bosch notice about this:

No idea about the holes...
Hi All, I work with these motors on a daily basis and I am amazed at the attitude towards motor maintenance? There are maintenance threads on shocks, forks, frames, group sets, dropper posts, cables, headstocks, bottom brackets etc. etc. But nothing on motors?

While these motors are in warranty it's obviously not a great concern, but many people are now coming to the end or are out of warranty and if you don't know what's going on in your motors you could be in for a nasty surprize!

If you use your bike for road work and clean it occasionally with a bucket and rag, then you can normally expect 6,000 to 8,000 miles (maybe more if you're lucky) The bearings and grease will wear out eventually if not looked after or re-lubricated.

A majority of the motors that I open up have had some sort of water contamination and this can wreck the bearings within 500 miles. If you ignore the grumbling in your motor or the play in your crank it will start to damage the surfaces that some of the bearings run on. The bearings are replaceable, the gears and shafts for most of these motors are not!

Please don't get me wrong, I am not here to scare anyone but from what I have seen, maybe popping the side cover off and taking a quick look at how things are getting on in there, is not a bad idea.(y)
Both of my Bosch units are new enough that I have the o-ring described in the document. I though it weird that it was so greased, since that attracts dirt, but I guess the grease just ends up being an extra seal.

In your opinion, is the maintenance something that can be done by a competent mechanic with a good toolbox? I already have the lockring remover, are any other special tools required?

Do you have a link to the service manual (in English)?
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Hi Honkinunit, The only tool you need, once the crank arms are off is a T25 Torx driver. You can then remove the side cover (Although depending on type of bike, you may have to drop the motor out? Again nothing special needed tool wise) Once the cover is off, you can see exactly what is going on in there. If you ride mostly dry trails I wouldn't bother, unless you're over 6,000 miles. But if you like to get down and dirty, it would be a good idea. If you feel it's time to re-grease everything I would follow my how to guides and videos. If you need to start changing some of the more tricky bearings, then a shop press is a must have.
Can somebody give me a link of tool need for removing the cranks? i'm not totally sure what exactly do I need. I have the bike on the first post :).

It this the correct tool: (the last on the list)
or this

I drive all the time, summer, autumn, winter, spring, and my bike gets quite dirty.

At least I would like to take the cover down and than proceed with further service if needed...additional greasing at first cannot do much harm. Probably any grease is fine?
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No! And stay away from those silly socket things! :unsure: You need a propper crank puller. google, ISIS Crank puller.
Take a look at some videos for removing the cranks. There are video's on youtube that are a bit clearer, just search YouTube for Bosch ebike crank removal. (y)
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