Bosch CX motor bolt torque specs — Focus Aventura?

[Ansgar]

Hey, torque on motor bolts bosch cx

I ride a Focus aventura.

 

[Greg Watts]

Hey, torque on motor bolts bosch cx I ride a Focus aventura.

Welcome to the forum, @Ansgar. The good news is that Bosch CX motor bolt torques are well documented, though the exact figures depend on which bolts you're talking about and which generation of CX your Aventura is running. Here's the breakdown.

There are two sets of bolts to be aware of. The larger bolts that go from the frame into the motor mounting plates (typically M8, Torx T30 or Torx Plus 40IP depending on generation) have a different torque to the smaller bolts that hold the mounting plates to the motor body itself.

As stated by Bosch, the two T30 Torx screws on the left side are 9 to 11Nm. If you have 13mm bolts with nuts on the other side, they are 25 to 30Nm. If you have bolts that screw directly into the frame, consult the bike manufacturer.

That last bit is key for the Focus, as frame material and thread design can affect what the frame can safely handle.

Bosch's general recommendation for the larger frame-to-plate bolts is 20Nm, but they advise checking with the frame manufacturer as carbon and alloy frames can differ. For the smaller mounting plate-to-motor bolts (the M5 ones that are notorious for coming loose), a Bosch service book confirmed the bracket screws should be torqued to 8Nm. A drop of blue Loctite on these is strongly recommended, as

they have a reputation for working themselves loose, especially on bikes that see regular trail use. For a quick reference on the common Bosch CX torque values:

Component	Torque (Nm)	Tool
Frame to mounting plate bolts (alloy frame, M8 with nuts)	25-30	13mm spanner / T30
Frame to mounting plate bolts (bolts into frame)	Check with Focus	Torx Plus 40IP (Gen4+)
Mounting plate to motor body (M5)	8	T25 or pentalobe TS25
T30 left side screws	9-11	Torx T30
Lockring	35	Bosch lockring tool
Crank arms	38-42	Crank bolt tool

One important tooling note:

Bosch recommend using a Torx Plus bit rather than a standard Torx bit for the motor mounting screws, as a standard Torx risks rounding the screw head.

On Gen4 motors specifically, you need the Wiha Torx Plus 40IP bit for the mounting screws.

Older generations may use standard T25 or T30 heads, so have a look at what's actually on your motor before you go reaching for tools.

I'd suggest contacting Focus directly for the frame-specific bolt torques on your Aventura, as those will depend on your exact model year and frame material. The motor-side values above are universal Bosch specs and won't change between manufacturers.