WATTSHOP Cratus Aero Crank Instruction Manual

: June 14, 2024
: WattShop

Table of Contents

Cratus Aero Crank
INSTALLATION GUIDE
SPINDLE/CRANK INSTALLATION
Documents / Resources
- Read User Manual Online (PDF format)
- Download This Manual (PDF format)

Cratus Aero Crank

Thank you for purchasing a WattShop #Cratus crank. We hope it serves you well in achieving maximum performance in all of your races! Please share your pictures
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WATTS IN THE BOX

No| Part Description| Quantity| Torque
1| Drive side (DS) crank| 1| –
2| Drive side (DS) dome| 1| –
3| Non-drive side (NDS) crank arm| 1| –
4| Spindle| 1| –
5| NDS bolt + washer| 1| 35Nm
6| NDS lock ring + washer| 1| –
7| Pedal inserts (LH and PH)| 1 (pair)| –
8| Pedal insert plates| 1 (pair)| –
9| M4x10mrn countersunk head bolts| 8| 2Nm
10| M3x6mm countersunk head bolts| 4| 1Nrn
11| Chainring bolts| S| 12Nm
12| Wave washer| 1| –
13| 0.5mm spindle spacers| 8| –

OPTIONAL

14| Charging| 1| –

NOTES

If you require a spindle less than 30rnm in diameter you will also receive .) spindle spacer

TOOLS REQUIRED

T10 Torx key
T20 Torx key
T30 Torx key
M10 Hex key| Chainring nut wrench
Torque wrench
Pin spanner

NOTES

T20 Torx key and the pin spanner wiil only be required if you disassemble that which has already been assemb ed.

WATTSHOP Cratus Aero Crank - Parts

The WattShop Cratus crank was designed to provide you with the narrowest Q-factor possible alongside optimised aerodynamics and crank arm adjustability. The latter is an interchangeable component with adjustability in 2.5mm increments from 160mm through to 175mm. Additional pedal inserts can be purchased separately via our website.
Please note if you have any custom aspects you may receive slightly different components to those listed above but this will be explained prior to shipping.

INSTALLATION GUIDE

You will find that your crank comes supplied with the DS crank (part 1), DS dome (part 2) and spindle (part 4) already pre-mounted using the 8x M4xlOmm countersunk head bolts (part 9) and 4x M3x6mm countersunk head bolts (part 10). If for any reason you disassemble these parts please follow the correct steps discussed further on in this guide to reassemble. This is an important aspect to ensure the chainring spins square to the bottom bracket.
The chainring (part 14)(crank specific or generic) can not be Manoeurved over the front face of the crankset therefore before installing the crank you will need to install the chainring. This is done from the reverse face. Using the 5x chainring bolts provided (part 11), installed and torque to 12Nm.
Use T30 torx key and chainring nut wrench.
Without using the wave washer (part 12) or 0.5mm spacers (part 13), slide the crank through your bottom bracket. With a 30mm spindle the NDS crank arm will engage directly. With smaller diameter spindles you will need to use the provided spindle spacer. This takes out the spindle to the correct size, matching the NDS arm.
The NDS bolt + washer (part 5) and lockring + washer (part 6) will already be installed when you receive the crankset. Note the NDS bolt will move freely. Using the 1Omm hex key and torque wrench install the NDS arm (part 3) and torque to 35Nm.
Once torqued we can now check for lateral movement and rotational resistance. Firstly, does your crank move left to right, if it does you will need to remove the crank and install the wave washer and/or the 0.5mm spacers to take up the slack. Do not install too many spacers, the crank has been designed to run with no spacers or at most, one or two depending on the BB cup size and this will affect the rotational resistance.
Once you have found the sweetspot check the rotational resistance by spinning the crank. If the crank is resticted in it’s rotation you have installed too many spacers.
Some BB cups sit slightly proud of the bearings on the DS. This can affect the set up. Unfortunately all we can recommend in this instance is to replace the BB with another brand or have the cup ring machined down.
The pedal inserts (part 7) can now be installed.
Ensuring the DS pedal is a standard thread and the NDS pedal is the LH thread, the insert is positioned trom the reverse side of the arm. Check you have installed these the correct way to achieve your desired crank arm length. The pedal plate (part 8) is positioned from the outside face into the corresponding recess, ensure you align the hole in the correct position. Finally install your pedals.

SPINDLE/CRANK INSTALLATION

If you have disassembled your spindle from the DS crank it will need to be reassembled in the correct order.
Please the see adjacent image. Assuming each bolt is numbered 1-8, they need to be installed as follows; 1-4-7-2-5-8-3-6.
The reason for this pattern is to ensure the crank is installed square.
Use the T20 torx key, loctite and torque to 2Nm.

WATTSHOP Cratus Aero Crank - Figure 4