As used by Dan Bigham & Filippo Ganna to break the UCI World Hour Record
As used by Dan Bigham & Filippo Ganna to break the UCI World Hour Record
As used by Dan Bigham & Filippo Ganna to break the UCI World Hour Record
As used by Dan Bigham & Filippo Ganna to break the UCI World Hour Record

Cratus Short Armed Crank

£890.00
1 review

SHORT VERSION 145-160mm. 

UPDATE. FROM 01.11.23 ORDERS WILL BE DISPATCHED WITH A REVISED CRANK DESIGN. THIS REDUCES THE Q FACTOR FURTHER TO 124.5mm (DOWN FROM 134mm).

The Cratus aero crankset has been designed to be class leading in every aspect from aerodynamics and drivetrain efficiency through to biomechanics and stiffness. The unique crankarm length adjustment system allows you to adjust between 145mm and 160mm (short arm crank) and 160mm and 175mm (long arm crank), making bike fitting and aero testing significantly quicker and easier. The super narrow Q factor of 124.5mm is class leading and helps to further improve both your biomechanics and aerodynamics. The proprietary aero chainring contains a range of unique improvements: stepped tooth to chainring profile reduces aerodynamic flow separation off the chain outer plates; 144 BCD reduces chainring flex, and the low friction additive infused material reduces surface friction to an absolute minimum.

The Cratus aero crankset is compatible with all pedal systems and various bottom bracket specifications, whilst also offering adjustable crankarm lengths through the use of interchangeable inserts. 

VIEW INSTALL GUIDE

Product Description

CRANK FEATURES

- Aerodynamically designed to reduce turbulence and separation around the spider, chainring and crankarm.
- 144mm BCD for track and road with 6mm thick chainrings, improving power transfer by eliminating any chainring flex.
- 124.5mm Q factor. Narrower than nearly every crankset currently on the market.
- Adjustable crankarm length between 145-160mm and 160-175mm at 2.5mm increments for each crank size. Also available in fixed crank length.
- Optional - road option comes with low friction additive infused 1x narrow-wide chainring in 58/60/62/64T.
- Optional - track option comes with low friction additive infused 1/8” track chainring in 58/59/60/61/62/63/64/65/66T.
- Stepped chainring design keeps the chain outer plates flush with the chainring to reduce air-flow separation with paired with our crank specific chainrings.
- Interchangeable spindle sizes.
- Compatible with all frames that run BSA, ITA,BB30, PF30, BBRight, BB30a, PF30a, BB90, BB86, Evo386, T45, T47/68, T47/86 bottom brackets.
- Laser etched WattShop logo to the drive side and non-drive side.

A full crankset consists of:

- 1x drive side and non-drive side arms
- 1x drive side dome cover
- 1x spindle
- 1x pair of pedal inserts and plates
- 1x retention bolt and washer
- 1x set of chainring bolts (male only)
- 1x set of hardware
- OPTIONAL 1x 6mm track or 6mm 1x chainring

NOTE

Standard 58t or larger 144BCD 5 bolt chainrings can be used with the crank. If you want to utilise this option please select "N/A" under chainring options. We recommend the Pyramid 144BCD 5 bolt track and 1x chainrings as compatible options (both available through WattShop). However it is optimal to have a Cratus specific chainring.

This crank is only compatible with 58T or larger chainrings and it is currently single ring only design. Chainrings can be ordered separately.
Please email info@shopforwatts.co.uk

Technical Specifications

WEIGHT

Drive-side crank and non-drive side arm: 685g
30mm spindle (alloy): 85g
24mm spindle (steel): 253g
Pedal inserts including steel plates: 75g (per pair)
66T chainring: 227g
SYSTEM WEIGHT (30mm spindle): 845g (excluding chainring)

CHAINLINE DIMENSION

24mm: 51.7mm
30mm: 49.6mm
30mm(+4): 51.6mm

COMPATIBILITY CHECK

When using on the road with an 11/12 speed cassette you may experience chain strike against the crankarm when in the smaller cogs. If this issue affects you, we recommend installing as many spacers as needed to the drive side. If the issue persists you will need a longer spindle. Please contact us at info@shopforwatts.co.uk and we can assist.

Customisation Options

CUSTOM

Custom spindles can be produced to accommodate nearly any bottom bracket/frame. Please email info@shopforwatts.co.uk to discuss your requirements.