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The Vision Metron 6D, as used by Vision's sponsored pro teams in the WorldTour, is a super-aero, super-stiff integrated cockpit with a comfortable, ergonomic shape that will reduce drag by a measurable amount compared with a round-profiled bar and separate stem. It's a lot of money to pay for a handlebar, but if all other aero and fitness bases are already covered it could be a worthwhile upgrade for serious riders looking to save watts on race day. However, it won't save any weight over the standard bar/stem and could be a bit stiff for less powerful riders.
Compared to deep-section wheels, integrated cockpits only arrived yesterday. This is because as wheel technology has matured, bike designers have turned to the other areas of the bike and have discovered that the leading edge – the bar and stem – is crucial in aerodynamics, and many of the top aero bikes already come with dedicated aero bar/stems by their house brands.
To put some numbers on it, Specialized claims its latest Aerofly II bar saves 20-plus seconds over 40km compared to a round bar. Meanwhile, by Zipp's calculations, its SL-70 handlebar creates just 0.11 Newtons of drag compared to a round-tube section handlebar's 0.74 Newtons, equivalent to a saving of 6.4 watts.
Vision does not supply any wind tunnel data for the Metron 6D – surely missing a trick here – and does not make any claims for the Metron 6D compared to its competitors, but it's likely that the lack of stem bolts and faceplate, combined with the smooth, uninterrupted sweep from the top and sides of the wing-shaped bar into the stem section, makes it pretty fast.
The 6D has a different shape from the 5D, which is still a current model. It is completely straight across the tops, like a standard bar, whereas the 5D is swept forwards.
Incidentally, there's a Metron 5D ACR (Aerodynamic Cable Routing) which completely conceals cables and hoses, taking them inside the stem and into the head tube – you would need to check your frame's compatibility – but no Metron 6D that does that (yet).
As for the Metron 6D's weight, well, Vision says it has a 'great strength-to-weight ratio', not claiming anywhere that it's light, and that will be because it's not: it was heavier by 15g than the fairly low-end aluminium ITM Visia bar and stem, including all bolts, that it replaced. I suspect that this is because pro bikes – even those with disc brakes – can now hit the UCI minimum weight limit easily, meaning a bit of heft can be built into the bars.
The Vision Metron 6D comes in a big box containing everything you need to set it up for all available types of braking and shifting. Underneath the stem is a compartment for a Di2 three-port junction box and there's a cover with included bolts and washer. It's also drilled for a Di2 bar-end junction box.
The internal cable routing holes look big enough for hydraulic hoses plus standard gear cables, and so will of course accommodate mechanical gear and rim brake cables. I'll admit I cheated and didn't cable them to capacity because my test rig is equipped with 'vintage' STIs with external cabling, which would cause a wind tunnel meltdown.
Regardless, Vision has ticked all boxes: the cable holes are directly opposite each other so there's no need to poke, force and curse cables and wires around tight corners and there's even a complimentary pair of plastic tweezers in the box to assist with this. They are actually just holes rather than channels inside the bar, so you do have to catch the cable end and hook it out.
There's a bag of optional proprietary aero spacers, including a dedicated top one that sits flush underneath the stem and one for the bottom of the stack that sits on the headset bearing, plus a top cap and even a bung.
None of the spacers is designed to sit above the stem, so you have to cut your fork steerer down if you want to use the Metron 6D-specific top cap directly on top of the stem. If you don't want to cut your steerer – as I didn't because I was only testing the bar – you can run standard round 1 1/8in spacers above it and then a regular round top cap, but that rather defeats the object of an aero bar.
On the subject of bar height, the Metron 6D only comes in a +/- 6-degree rise – although there are different stem lengths and bar widths to choose from – so before you buy you should do some careful trigonometry to make sure it's not going to wreck your bike-fitted position.
Vision also supplies an out-front Garmin mount plus a generic-computer out-front mount. I used the Garmin mount and found it was more solid than some tri-bars I've used in the past. There was no vibration at all and the Garmin clicked in very firmly. If you fancied 'doing a Hirschi' and using your computer/computer mount as tri-bars, this would be more than up to the job.
All of the Metron 6D's 40cm, 42cm and 44cm width options come with an 80mm reach and 125mm drop, which broadly classifies them as compact, making them easy to ride with minimal change to overall position for the changes in hand position.
Once I got my contact points there or thereabouts using round spacers, as mentioned, I found the Metron 6D comfortable to hold. The tops supply a bit of extra surface area while climbing, the flat section as it turns through 90 degrees to meet the shifters also gives the heels of the palm a bit more support, while the classic bend of the drops felt nice and familiar, just like any other bar.
However, while it was great ergonomically, I found the sheer stiffness a little excessive for even a two-and-a-half-hour group ride in the lanes, even though it was a fairly pacy one. I am prepared to admit that I'm not the most powerful or heaviest rider, and since this bar was developed with Vincenzo Nibali and the Merida team then it's hardly surprising that it's overkill for many less powerful riders.
Its extreme rigidity showed up the flex in my bike's front end, which wasn't noticeable with a common-or-garden bar and stem.
Vibration damping on smoother tarmac was great, especially with a quality bar tape like the Arundel Art Gecko (which, incidentally, is reusable after all).
I concluded that in order to get the ride quality out of the Vision Metron 6D that it is designed to give, you need to be a powerful rider and you need to fit it to a bike that's itself already very stiff. Vision can't be criticised for this: the Metron 6D was developed for pro riders, after all.
Yes, yes, you could buy a whole bike for less, but the Vision Metron 6D is by no means the most expensive integrated cockpit out there. In 2018 we reviewed the Deda Alanera, which cost £699 at the time and the updated version with more integrated cabling costs the same.
Even more expensive is the MOST Talon Ultra, at £750, which is only compatible with the Pinarello Dogma F12.
The Trek-specific Bontrager Aeolus RSL VR-C integrated bar/stem is a little cheaper at £549, while the PRO Stealth Evo costs £449 and is compatible with any bike. And there are, of course, Chinese carbon bars that are cheaper still.
So the Vision Metron 6D is not outrageously expensive in the integrated cockpit market by any means.
We don't have the capacity to aero test at road.cc, so I don't have any of my own data to prove that the Metron 6D was faster than the round-profile bar, or indeed any of the above bars. However, there's enough out there already to prove that aero bars are faster than round ones – that's not in doubt.
In summary, the Vision Metron 6D would be the missing piece of the aero jigsaw for a rider who has already invested in aerodynamics, is at the top of their fitness game and is prepared to spend the money to get that little bit more out of their performance, but if you're not a serious racer there are upgrades that are easier on the body, and the Metron 6D won't save any weight over a standard setup.
Uncompromisingly stiff aero cockpit that's perfect for strong racers looking to save watts but not shave grams
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road.cc test report
Make and model: Vision Metron 6D Integrated Bar and Stem
Size tested: 420x110
Tell us what the product is for and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
Vision says: "Metron 6D integrated handlebar [is] the stiffest and most aero integrated handlebar and stem system. Mixing aerodynamics and ergonomics, the unique shape includes our Aero-Ergo central section. Reinforced carbon-fibre construction gives a great strength-to-weight ratio. The 6D features internal cable routing, with guides that accommodate wiring for electronic shifting. 0° forward angle for the rider who is looking for a more traditional position on bike."
Tell us some more about the technical aspects of the product?
Continuous carbon composite construction
Aero-Ergo flat-top riser central section
Straight top (0° Forward angle)
Cable groove compatible with new Di2 systems w/ larger internal cable tunnel
Reinforced and textured lever area
Colour: UD carbon finish
Colour graphic options: grey
Stem angle: -6°
Includes: standard computer mount, Garmin computer mount, spacers kit, carbon top cap, compression device and junction box cover.
Top marks for performance.
As with anything carbon you've got to look after it, but it's a pretty solid lump of material.
Doesn't save any weight over a standard aluminium bar and stem – in fact is slightly heavier.
Vibration damping on rough roads is not the Vision Metron 6D's forte, but from an ergonomic point of view it is comfortable.
Sits in the middle of the carbon integrated cockpit market.
Tell us how the product performed overall when used for its designed purpose
It was designed to be super aero and super stiff and it is most definitely both of those things. Integration is good for a third-party bar, but the proprietary cockpits – such as with the latest Canyon Aeroad – offer even more integration.
Tell us what you particularly liked about the product
Lovely aero design, high-quality finish, great attention to detail with everything supplied in the box to facilitate any setup.
Tell us what you particularly disliked about the product
For me personally it was too stiff, but more powerful riders, especially sprinters, will welcome its rigidity.
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
The Vision Metron 6D is by not the expensive integrated cockpit out there. In 2018 we reviewed the Deda Alanera, which was £699 at the time and the updated version with more integrated cabling costs the same. Even more expensive is the MOST Talon Ultra at £750, which is only compatible with the Pinarello Dogma F12. The Trek-specific Bontrager Aeolus RSL VR-C integrated bar/stem is a little cheaper at £549, while the PRO Stealth Evo costs £449 and is compatible with any bike, and there are of course Chinese carbon bars that are cheaper still.
Did you enjoy using the product? Yes
Would you consider buying the product? No, because it doesn't work for my type of riding.
Would you recommend the product to a friend? Yes, if they were a serious racer.
Use this box to explain your overall score
This an an awesome piece of pro-level kit that is meticulously designed, has a high level of compatibility, a high-quality construction and finish, and is undoubtedly more aerodynamic than a round bar and standard stem. It's expensive, but the price is in line with other integrated carbon cockpits. It's a pity we don't get to see any actual wind tunnel or aero data and it would be nice if it had a weight advantage as well as an aero advantage but, as I mentioned, pro-level bikes probably don't need lightweight bars any more.
About the tester
I usually ride: Racer Rosa custom alu My best bike is: Colnago Master Olympic
I've been riding for: Over 20 years I ride: Most days I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, touring, club rides, sportives, School run on a tandem