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If you can't quite achieve that low race position with your standard headset then this Cane Creek Slamset ZeroStack (ZS) Top Assembly could be just what you are after. Your stem will be suitably slammed for that pro look and thanks to the sealed Hellbender bearings, keeping the elements out won't be a problem either.
Many headset top assemblies can sit around 10mm proud of the top of the head tube, the equivalent of having another spacer between it and your stem. If you want to really get as low as you can at the front end, the ZS reduces that height to just 2mm, and that can be quite a noticeable difference.
The ZS model is an internal/integral style headset that will fit your head tube if it takes a 44mm diameter bearing cup. It drops into your frame and then the bearing race is positioned inside that. The top cover then tightens in on top of that for a very clean looking and enclosed assembly.
The cups and covers are made from 7075-T6 aluminium alloy and are nicely finished, feeling totally smooth inside and out.
At its heart, the ZS uses Cane Creek's stainless steel Hellbender bearings which are designed to resist corrosion and stand up to the elements – should any get in. The headset has seen plenty of rain and mud over three months of testing and on inspection still looks like new.
Once assembled and adjusted, the whole setup felt completely smooth and that hasn't changed during testing. I'll keep an eye on things over the winter when the real abuse should start, but this is looking like a fit and forget item for many seasons to come.
If you have an integrated style head tube where the bearing race sits directly into the frame then Cane Creek also offers IS versions (£49.99). These don't give quite as low a stack height as the ZS, but you are still only looking at 4.6mm above the top of the head tube.
Both the ZS and IS versions are available as full assemblies too.
When it comes to value, the ZS is a bit of an outlay at £74.99, especially when you can get the highly regarded Hope Technology Integral headset for around £40. It doesn't offer anywhere near as miniscule a stack height as the Cane Creek, mind.
Overall, the Zerostack is a very smooth headset that's simple to fit and adjust, and though it isn't cheap it should last you a long time.
Well-made headset that delivers a racy position while keeping out the elements
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road.cc test report
Make and model: Cane Creek Slamset ZS44/28.6 headset top assembly
Size tested: ZS44/28.6
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?
Cane Creek says, "The Slamset is a premium headset created for riders seeking to lower their handlebars further than the standard stack height without compromising bearing seal and proper preload. With the HELLBENDER bearing included, the Slamset excels at durability and longevity when it comes to steering performance."
Tell us some more about the technical aspects of the product?
CUPS AND COVERS 7075 T-6 Aluminum, contoured and relieved to minimize weight and maximize strength
TOP COVER Low-friction upper bearing seal completely seals cup from contaminants and is fully captured by the top cover with no loose parts
CROWN RACE Aluminum crown race with integrated low friction seal
COMPRESSION RING Carbon friendly cap-in compression ring
Top BEARING HELLBENDER, sealed stainless-steel bearings
Bottom BEARING HELLBENDER, sealed stainless-steel bearings
MANUFACTURING Assembled In USA
External Cup (EC) '' 12mm bottom
ZeroStack (ZS) '' 2mm top, 4mm bottom
Integrated (IS) '' 4.6mm top, 1mm bottom
FINISH Anodized Aluminum
Tell us how the product performed overall when used for its designed purpose
The handling feels smooth and it keeps the weather out.
Tell us what you particularly liked about the product
Well sealed against the elements.
Tell us what you particularly disliked about the product
Quite an outlay.
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
At the higher end of the market but it does have that zero stack height USP.
Did you enjoy using the product? Yes
Would you consider buying the product? Yes
Would you recommend the product to a friend? Yes
Use this box to explain your overall score
It's a little pricey compared to some of the opposition, but it's well made and performs very smoothly.
About the tester
I usually ride: This month's test bike My best bike is: B'Twin Ultra CF draped in the latest bling test components
I've been riding for: Over 20 years I ride: Every day I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, club rides, sportives, fixed/singlespeed
As part of the Tech Hub here at F-At Digital, our senior product reviewer Stu uses the knowledge gained from putting well over a 1,000 products through their paces (including hundreds of bikes) to write in-depth reviews of a huge range of kit. After first throwing his leg over a race bike back in 2000, Stu's ridden more than 160,000 miles on road, time-trial, track, and gravel bikes, and while he's put his racing days behind him he still likes to smash the pedals rather than take things easy. Although, as he spends a fair bit of his time reviewing ebikes these days he's becoming an expert in letting the motor take the strain. He's also waiting for 23mm race tyres to make a comeback!