The last CNC technology is also available for small wheelers. Pneuma cranksets brings the ultimate crankset technology to our commutes.
Most folding bikes are built with heavy cranksets with outdated square taper bottom brackets. To make things worse, finding high quality and light cranksets for folding bikes is not an easy task because they need MTB style spacing and road style chainring sizes. This is why most standard cranksets are poor fits for folding bikes. Ridea designs their cranksets for folding bikes with the correct specifications fit the requirements of folding bikes.
Pneuma BCSA is our best ever single chainring crankset for Brompton, Birdy, Dahon, Moulton and many other folding bike brands.
| P/N | Pneuma BCSA |
| Crank material | CNC AL7150 (Sekoan crank arm) |
| Crank arm length | 170 mm |
| Spider mount positions | Three, in 10° steps |
| BCD | 130 mm 5 arms |
| Weight | 480 g (170 mm; TI64-24 mm spindle; w/o chainring) |
| Ridea chainrings | LamiFlow R5ST series (1x) |
| Colors | Black (more colors are available as a customization option) |
| Spindle diameter | Spindle material | Spindle length | Bearing contact area | Chain line | Q factor |
| 24 mm | SCM440 or TI64 | 130 mm | 96 mm | 48 mm | 164 mm |
Modular system
Pneuma cranksets are fully modular. The different parts (crank arms, spindles, power meter spiders, spiders and chainrings) can be mixed and matched to suit every rider specific needs. Your crankset can change with you at the same time that you change your riding style or your fitness.
The only limitations are that 29 mm spindles require specific Pneuma crank arms for 29 mm, and vice versa with 24 mm. Also, the BCD and number of bolts for both the spider and the chainrings must be the same. Other than that, you can mix and match Pneuma crankset parts to best suit your needs.
A new concept of hollow crank
All high-end cranks try to reduce weight by reducing the quantity of material used. Most cranks, despite the external appearance, are more or less hollow in the inside. Although in most cases, hollow cranks work flawlessly during the whole expected life of the crankset, sometimes moist and humidity can build up in the interior, leading to corrosion or rust and, eventually, crank failure.
The design of the Pneuma crank reduces the weight while retaining an optimal weight/stiffness ratio, as well as completely eliminates the possibility of corrosion or rust building up in hidden areas.
3 spider-chainring positions for your Powering
Pneuma spiders can be installed in three different angles, with ten degrees of separation between each position. When using oval chainrings like the Ridea Powering, this feature can be used to adjust the position of the biggest and lowest ratio of the chainring in relation to the crank arms, in order to better adapt to you riding preferences and musculature.
24 mm and 29 mm spindles
Ridea designed the first 29 mm diameter spindle back in 2012 with the ES BB29 series. Pneuma cranksets inherit this innovation and are available in 29 mm versions, which are compatible with other 29 mm solutions in the market like SRAM’s DUB™. Needless to say, Pneuma cranks are also available with 24 mm spindles, which again are compatible with other solutions like Shimano’s HOLLOWTECH II.
Available spindles for Pneuma cranks
The following table shows all the available spindles for Pneuma. Highlighted in gray are the spindle type(s) that is(are) standard for this specific crankset model (Pneuma BCSA). Other spindles can be installed to suit specific needs.
| Spindle model | Bearing race diameter | Bearing race distance (outer-to-outer) | Bearing race distance (inner-to-inner) | Total length | Material | Weight | Application |
| R410 | 24 mm | 92 mm | 70 mm | 126 mm | SCM440 or TI64 | 111 g (steel) 62 g (Ti) | Road, single speed and track bikes |
| M411 | 24 mm | 96 mm | 74 mm | 130 mm | SCM440 or TI64 | 118 g (steel) 68 g (Ti) | MTB 135-142 mm Brompton Birdy (1x) |
| M412 | 24 mm | 102 mm | 74 mm | 136 mm | SCM440 or TI64 | 124 g (steel) 69 g (Ti) | MTB 148 mm Birdy (2x) |
| M413 | 24 mm | 105 mm | 74 mm | 139 mm | SCM440 | 126 g | MTB 157 mm |
| R910 | 29 mm | 92 mm | 70 mm | 126 mm | AL7075 | 87 g | Road, single speed and track bikes |
| M911 | 29 mm | 96 mm | 74 mm | 130 mm | AL7075 | 92 g | MTB 135-142 mm |
| M912 | 29 mm | 102 mm | 74 mm | 136 mm | AL7075 | 96 g | MTB 148 mm |
| M913 | 29 mm | 105 mm | 74 mm | 139 mm | AL7075 | 98 g | MTB 157 mm |
