BREW Nitro Shox
We first showed you BREW's interesting Nitro Shox at last year's Eurobike tradeshow, and since then the UK company has been working away to get the shock ready for production. That includes some internal fine-tuning, a change from the anodized blue shock body shown here to a black finish that won't stand out as much, and some added adjustments. BREW is aiming to launch the production version this coming September, sometime after the Interbike tradeshow, and they told me that pricing should be similar to high-end offerings from established brands.
Nitro Shox Details:
• Intended use: all-mountain / enduro / DH
• Oleo damper design
• Nitrogen spring
• Three spring rates from factory
• Adjustment dial to tune spring rate
• Adjustable rebound and compression
• Weight: TBA
• Availability: September
• MSRP: TBA
What's not similar, however, is how the Nitro Shox goes about doing its job. What's Different?
The Nitro Shox's oleo damper is relatively simple compared to a run of the mill mountain bike shock. To start with, there's a nitrogen pressurized chamber that's separated from the damping oil by a piston that we'd usually refer to as an IFP (internal floating piston). This nitrogen charge acts as the spring, whereas the pressurized chamber on the opposite side of the IFP is used to provide back-pressure and room for oil displacement within a traditional shock.
When the BREW shock is compressed, the damping oil pushes on the IFP and the nitrogen charge is compressed - this gives you your spring rate. On the opposite end of the shock is a tapered metering pin that aligns with a bleed hole on the metering / damping orifice, and this is what determines the amount of pressure that's applied to the IFP and the nitrogen charge. This means that it's able to supply as much spring force as required when there's a massive impact, but then also bleed off that pressure as needed. In short, it provides both a non-linear spring rate and non-linear damping force that allows it to react in a way that a standard shock would never be able to, and, according to BREW's Joe Hunter, in a way that gives the rider more control.
BREW actually sets the shock's nitrogen pressure, which they say is a bit higher than the pressure used in the latest high-volume air shocks, at the factory before shipping the shock out to the customer. This means that, for the most part, the shock's spring rate is set because this nitrogen charge is your spring.
Some adjustment is built-in via a rotary dial that will be on the production shock's piggyback, the turning of which will move nitrogen either in or out from the piggyback into the main chamber. It's clear that one of BREW's main challenges will be convincing riders that they don't need to adjust anything on the Nitro Shox, which won't be an easy task given that the more-is-better attitude is prevalent when it comes to suspension adjustments.
Hunter says that because the damper is velocity dependent, it's able to match the forces put into the shock and self-adjust, meaning that riders shouldn't have to turn any dials. In fact, they had originally considered offering a shock with basically zero damper and spring adjustment but have since softened that stance. The production shock will now sport two dials, one to adjust rebound and the other compression, that will allow for some manual tuning on top of the shock's self-adjusting nature.
I'll be spending a few days on BREW's Nitro Shox while in the Whistler Bike Park when they bring over a production sample this coming September, so stay tuned for ride impressions.