The new Scott Plasma 5 triathlon bike takes the rider-and-bike combo and aims to make it as fast as possible. They say this bike is faster with the rider on it and with all the storage and hydration solutions mounted. More stuff on board plus more system integration equals more aero.
It’s also meant to be more comfortable for a wider range of riders thanks to a plethora of adjustments and options. Those include three base bars, two different stem styles and much more. The frame and overall design makes it stiffer, too, with a few bits adding durability as well. Even if you’re not into tri and TT, the execution is worth a look.
Despite appearances, it’s completely UCI legal. Well, the bike is anyway – the bento box and battering ram water bottle don’t pass inspection.
Oh, and no, they didn’t just jump from Plasma 3 to 5, there’s a new Plasma 4 in the line, also, bridging the gap between the old and new…
To improve aerodynamics, they took advantages in the ever improving CFD software to analyze more and more detailed interaction between airflow, the bike, its parts and the rider. That led to changes in tube profiles as they run down the frame. The claimed effect is that wind turbulence and attachment/detachment points were optimized based on what’s happening around tubes (the seat tube in particular) as wheels, legs and cranks are spinning past it in various directions, all in random opposition to the air breezing past the whole enchilada while riding.
Part of making something aero is integrating as much as possible, and we’ve seen various designs to smooth the transition from stem to frame. Scott made it as flush as possible, but moved the upper headset bearing above the stem, allowing for wider bearing placement to torsionally stiffen the steering system by 47% compared to the Plasma 3. This allows for a 90g lighter stem than the Plasma 3, also, and brake cables and shift wires are able to run from inside the handlebar into the body of the stem and directly into the frame above the top bearing, keeping them hidden from stem to stern.
Two stems are offered, a 0mm rise for TT and 45mm rise for triathlon. Base bars come in three options:
- +30mm rise / 420mm wide
- 0mm rise / 420mm wide
- -30mm rise / 400mm wide
The base bars’ handles are left intentionally long and can be cut down by up to 15mm. The aero extensions are a standard 22.2mm diameter, allowing any to be used, but Scott had Profile Designs develop a new aero extension system for the Plasma 5 that offers up to 75mm of spacer height adjustment, numerous pad mounting positions to dial width and aero covers for the back of the spacers to hide shift wires.
Directly in front of the head tube is an aero cover that hides the cable leading to the front brakes. They worked with TRP to develop a new single bolt, dual pivot brake with a lower profile so it’d fit under the cover. They also designed it with a higher leverage ratio and more arm movement per lever pull, allowing it to provide strong braking with good modulation. While the arms and design are new and proprietary, they use most of TRP’s existing hardware to make service easier. They even gave the bike both standard single bolt and dual bolt direct mount options, so you can run any brakes you want up front – you just won’t be able to use the aero cover with other calipers.
So far, we’re all good for sanctioned TT races, too. The frame and handlebar are UCI compliant. Where we run afoul is with the included top tube storage box and aero front mounted water bottle. The box streamlines the transition from the taller Tri stem and is large enough to hold eight energy bars (or your own combo of food, tools, tube, CO2, etc.) and has a divider insert to keep things organized. It bolts on with standard water bottle bolt spacing, so you could replace it with an extra bottle cage. The water bottle comes in two sizes to fit different frame sizes, offering 550ml (~18.5oz) or 625ml (21.1oz) of drink. It clips on to the front of the stem and sits flush with the rest of the front end to improve aerodynamics even further. A wide mouth opening on top makes for quick refills and a straw puts beverage access right where you want it when tucked.
We’ll be at Scott’s press launch this weekend and have some hands on photos and more details on this bike and others. In the meantime, here’s a little video run through, followed by models/spec lists:
MODELS & SPECS
Below the Plasma 5 is the new Plasma 4, changes the frame up a bit and loses some of the integrated aero features. More on this model coming soon.