Torque settings for Bosch CX motor?

Barrio Barranco

Esteemed Pedelecer
Nov 24, 2018
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Today I fitted my Purion controller and finally ditched the brick Intuvia. All went relatively well- there's a stupid bolt on the plastic sump guard highest up the downtube which when undone lets the nut fall into the frame amongst the battery mountings and all the cables....total faff to get it out. Also the frame grommet needed cut as there was no way the connector was going through the small diameter hole, but now it's back in place you'd never know....
So- replaced the 2 motor>frame gaskets and currently I've torqued(not a ratchet one but Park "bendy bar"(!) the 3 larger bolts on the RHS to 25Nm, and the 2 on the left hidden under the cover by the electrical connections to 11Nm Using a Park ratcheting torque wrench?
Anyone got a more accurate idea of what it should be and/or whether this is ok? All bolts seemed really easy to take out btw? I've based them figures on Googling but they may be for the Active Line??
 

Barrio Barranco

Esteemed Pedelecer
Nov 24, 2018
281
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So someone posted up this on here....which probably needs removed....IMG_0366.JPG

So I put the TW5.2 to 14Nm from the 11Nm I'd set it at and tried nipping up the bolt on the front LHS, it all looked to be going well until the wrench wouldn't click and I had that sinking feeling of "OH F**K....this isn't getting any tighter....."

Then I went back to the original thread.....

"Thanks for info, very helpful, but a slight correction. Translating the attached doc, both T30 bolts should be torqued to 9-11 Nm ("folgemontage" in german means follow up assembly, not rear). "

Oh well, time will tell if it starts creaking....but this thread needs removed (yes my fault for not reading it through but a screenshot of an official Bosch page made me stop there... fool!!!)
If it does we have a local blacksmith who is sh*t hot I'll just have to see if he can rethread it or something....but I'm a bit annoyed right now!!!
 
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Barrio Barranco

Esteemed Pedelecer
Nov 24, 2018
281
99
55
Thought I'd update this... I took the bolt back out and marked a spoke as a depth gauge and realised that the hole wasn't tapered, may well have a good 5 mm more depth so then put the vernier calipers on what should be an M6 bolt. it was 5.75mm at the front end and 5.8mm at the back end.
I measured a brake caliper mounting bolt and it was 5.9mm wide, and found one a couple of mm longer than the original which when put in tightened up nicely- I've not used the torque wrench just done it by hand as I'm not even sure whether to trust the bloody wrench... now just leave the thing alone!!!!
The original bolt is a "10.9" hardness rated one so Bosch have correctly given torque settings for the bolt- but I was in the blacksmiths dropping off a trailer from work and told him all of this and he was horrified that 13-15Nm was quoted at all... the 9-11Nm is suitable for the next bolt down in hardness- an "8.8" which is what the caliper bolt is presumably as their range is stated as 8-10Nm....
Did a 60km ride on Saturday and nothing is creaking so deffo time to just leave it alone !!!
 

Vim Fuego

Pedelecer
Mar 21, 2021
63
3
So someone posted up this on here....which probably needs removed....View attachment 31114

So I put the TW5.2 to 14Nm from the 11Nm I'd set it at and tried nipping up the bolt on the front LHS, it all looked to be going well until the wrench wouldn't click and I had that sinking feeling of "OH F**K....this isn't getting any tighter....."

Then I went back to the original thread.....

"Thanks for info, very helpful, but a slight correction. Translating the attached doc, both T30 bolts should be torqued to 9-11 Nm ("folgemontage" in german means follow up assembly, not rear). "
Sorry for bumping an old thread. I'm pondering doing a nyon upgrade on my Performance Line Bosch based ebike (haibike Sduro 3.0 2020), as all my local bike shops are incapable of even basic things like answering emails, let alone bike servicing.

I've not looked in detail at how the motor is mounted to the frame, but as I understand it, there are 5 bolts needed to drop the motor (to fit the cable down the frame). Are these all T30 torx, and all need tension of 10Nm ?

I'm not sure what the "TW5.2" refers to...

I'm thinking it should be no more complex than removing the plastic cowel, getting access to the mountibg screws to drop the motor, the run the cable, refit the motor and tighten to specified torque.

I've seen a YouTube video where then can be done without even removing the crank.


Thanks
 
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