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The Bontrager Pro IsoCore VR-CF handlebar provides added comfort thanks to a novel carbon fibre layup and foam inserts, but the difference to a regular carbon handlebar isn't significant enough to justify the high cost.
When Trek launched its new Domane SLR, not only did it take its unique Isospeed decoupler technology to the next level, but it also introduced the new Pro IsoCore VR-CF handlebar (Trek being the owner of the Bontrager brand).
While it looks like any normal carbon fibre handlebar, Bontrager has taken a two-pronged approach to achieving what it claims is a 20% reduction in road vibration.
First, there's a special carbon fibre construction process that fuses an elastomer material into the OCLV carbon layup and helps to damp vibrations. Secondly, there are shallow recesses on the handlebar, on the tops and in the drops, that let you fit IsoZone EVA foam pads.
I've spent considerable time using the handlebar, both on two versions of the new Domane SLR, as well as testing it on my own bike where I've been able to really get to know it.
It does help in the battle (if it can be called that) against unwanted road vibrations and chatter felt through the bars. It's not quite like bolting a suspension fork to the bike, but it goes some way to eliminating some of the jarring sensation that can be felt through your hands and arms when encountering road surfaces that are far from billiard table smooth.
I tested the handlebar with and without the extra foam pads for comparison (they fit as shown here). There's a noticeable difference between the two, as you'd expect. With the foam pads fitted and wrapped with high-quality bar tape, there's a level of cushioning you might get if you double wrapped the bar tape, but without the extra thickness associated with such a setup.
With the handlebar wrapped without the foam pads, the cushioning effect is diminished but the handlebar still provides a smoother ride compared with a regular carbon handlebar. Really, if you're looking to buy this bar you're clearly interested in comfort, and it makes sense to utilise the EVA pads to maximise the vibration absorbing qualities.
Where the handlebar's construction is most noticeable is riding in the drops. There are obviously the effects of leverage at play when riding in the drops, but smoothness was most noticeably ramped up when using the drops compared with other carbon handlebars. It's noticeable, but to a lesser extent, when riding on the hoods.
I'm not convinced about Bontrager's claim of 20% reduced road vibration, though, especially compared with many of the very good carbon handlebars also available in this price range, but there is definitely a small difference that might be enough of a gain to warrant choosing this over another carbon bar.
There's no lack of stiffness when riding hard and fast, and out-of-the-saddle sprints don't reveal any vagueness at all.
It's available in four widths from 38 to 46cm. I tested the 42cm as that's my personal preference. The shape of the bends is shallow and short, with a 123mm drop and 93mm reach, with a nice curve that provides several comfortable positions for your hands. The handlebar is also compatible with clip-on extension bars in case you're doing some time trialling.
It's a smart looking handlebar with a nice glossy appearance and markers to make lining up the brake levers and stem easily. While some might dispute fitting Bontrager components to any bike other than a Trek, I found it didn't look out of place on other bike brands at all.
Naturally, it's being specced on Trek's latest Domane SLR endurance bikes but there's no reason why you can't use it on anything from a touring and audax bike to a gravel and adventure bike if you're searching for a bit of extra comfort.
To sum up, the comfort this handlebar offers won't radically change your ride, but it does go some way to offering a small amount of extra smoothness, especially ideal if you regularly ride rough roads or cobbles and want a bit of vibration damping. I won't be taking it off my bike anytime soon, that's for sure.
Carbon handlebar with foam pad inserts provides a smoother ride but at some cost
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road.cc test report
Make and model: Bontrager Pro IsoCore VR-CF Road Bar
Size tested: N/A
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?
Bontrager says: "A chain-rattling road is no longer an issue thanks our innovative IsoCore technology in this Pro IsoCore VR-CF road bar. An additive to the carbon lay up, IsoCore mutes 20% more vibrations than other carbon bars. Once you experience the comfort and control of IsoCore, you'll never want to ride another bar."
Tell us some more about the technical aspects of the product?
OCLV carbon with IsoCore continuous inner-laminar technology
Replaceable IsoZone EVA pads maintain the original grip diameter
The Variable Radius Compact Flare (VR-CF) bar shape offers greater comfort in all hand positions
IsoCore technology decreases road vibration by 20% over traditional carbon bars
Compatible with clip-on aero bars
Includes four replaceable EVA IsoZone pads for tops and drops
It's an expensive handlebar, but if you're looking to gain more comfort this might be a good last resort if you've already looked at other areas.
Tell us how the product performed overall when used for its designed purpose
Works well for the intended riding.
Tell us what you particularly liked about the product
Provides a little extra comfort over other bars.
Tell us what you particularly disliked about the product
The difference between this and a regular carbon bar isn't huge.
Did you enjoy using the product? Yes
Would you consider buying the product? Maybe
Would you recommend the product to a friend? Maybe
Use this box to explain your score
It's a nicely made bar and easy to set up, and the foam pads are a great idea, plus there's a small comfort improvement... but it's tricky to back up Bontrager's 20 per cent claim of reduced road vibration compared with other carbon bars.
About the tester
I usually ride: My best bike is:
I've been riding for: 10-20 years I ride: Every day I would class myself as: Expert
I regularly do the following types of riding: road racing, time trialling, cyclo-cross, commuting, touring, mountain biking
David worked on the road.cc tech team from 2012-2020. Previously he was editor of Bikemagic.com and before that staff writer at RCUK. He's a seasoned cyclist of all disciplines, from road to mountain biking, touring to cyclo-cross, he only wishes he had time to ride them all. He's mildly competitive, though he'll never admit it, and is a frequent road racer but is too lazy to do really well. He currently resides in the Cotswolds, and you can now find him over on his own YouTube channel David Arthur - Just Ride Bikes.