Starting life by CNC machining environmentally friendly pedals, Pembree has quickly expanded, and the GCS Stem comes as part of a swathe of new kit from the brand. Built for gravity riding, it marries good looks, a top-notch build quality, and great performance. However, it requires a fair bit of torque, and combined with perhaps a little too much pre-applied Loctite, on-trail tweaks aren’t easy.

Pembree GCS Stem – Technical details

The GCS stem is built to cope with the rigors of enduro, freeride, and downhill, passing the EFBE Gravity Tri Test that officially approved it for such riding styles.

025 pembree gcs stem front.jpg
025 pembree gcs stem front (Image Credit: Farrelly Atkinson)
025 pembree gcs stem front.jpg, by Liam Mercer

With that in mind, it features a wide clamp zone to achieve a solid clamp between the stem itself and a handlebar. The stem then uses steel bolts to hold it all together, and they’re equipped with washers to stop the bolts from wearing into the aluminum under torque.

Of course, as expected from Pembree, the GCS is a CNC-machined stem, using 75% recycled aluminium. It’s available in 31.8 and 35mm clamp diameters and only a 35mm length. Additionally, its stack measures 40mm, and there’s no rise.

The stem weighs 174g and it’s available in six anodised colours.

Pembree GCS Stem – Performance

If Pembree has made its name for anything, it’s the quality of its machining, and that’s certainly present on the GCS. Each face is beautifully smooth, and each line is sharp. It’s an excellent-looking bit of kit, especially with the laser-etched, but rather low-key Pembree logos.

025 pembree gcs stem centre.jpg
025 pembree gcs stem centre (Image Credit: Farrelly Atkinson)
025 pembree gcs stem centre.jpg, by Liam Mercer

It’s clear that the brand has gone the extra mile, too, machining markers into the stem’s aluminium for the no gap interface, the Newton metre designation, and a very handy centre mark to help line up bar placement. It just so happens that it works well with the brand’s own GCS handlebar. Because of that, it’s easy to set up, and the 5mm Allen bolts provide a larger interface that’s tougher to round out under the higher torque loads they require (9Nm around the stem). Because of that comparatively high torque requirement, the inclusion of washers around the bolts makes total sense, as they stop the turning of a bolt from marring its surface.

Along with excellent looks, the GCS brings great performance. The wide clamping area brings solid stiffness, which then results in a direct steering feel. Elsewhere, it works exactly as a good stem should. 

025 pembree gcs stem newton.jpg
025 pembree gcs stem newton (Image Credit: Farrelly Atkinson)
025 pembree gcs stem newton.jpg, by Liam Mercer

While most stems are pretty much fit and forget, the GCS’s key downside lies in that lofty torque specification. 9Nm for a stem is quite a lot, where four to six Newtons are the norm, and the need to tweak a stem on the trail is an inevitability, whether it’s to tighten a headset or straighten a bar.

Throw in the Loctite-coated bolts into the mix, and it’s a tough stem to adjust with a multitool, and because the Loctite adds friction to the bolt, a torque wrench’s readings can be skewed. This means that even though my torque wrench has read 9Nm when nipping up the bolts, the stem can still rotate on the steerer tube as the extra friction causes the torque wrench to read at a higher torque than is actually reached.

025 pembree gcs stem top.jpg
025 pembree gcs stem top (Image Credit: Farrelly Atkinson)
025 pembree gcs stem top.jpg, by Liam Mercer

Adding a bit of chain lube (of course, grease would be better, but this was an emergency) to the bolts solved this issue right away, but still, 9Nm is quite a lot to ask, especially when attacking the bolts with a multitool. Perhaps in my case, there was just a little too much thread lock on the bolts, and upon my initial installation, the stem torqued up just fine. Of course, thread lock can be removed, and by doing that, you’ll make the stem easier to adjust.

I moan, but I’m not without some partial blame here. I should set up my headset properly before riding, or even leaving the house, as should everyone. So it’s not completely the stem’s fault.

Pembree GCS Stem – Verdict

At £130, the GCS is definitely a more premium offering, squaring up against the likes of the Renthal Apex stem, which is cheaper at £117, and lighter at 125g. However, while it’s a favourite, it comes in one colour, there’s no record of it being EFBE certified, and there are no markings, so it’s not quite as easy to line up a handlebar perfectly.

Coming in at £85 is the GCS stem’s real contender, the PNW Components Loam stem. It’s a little lighter at 166g, but it’s built to a similar quality. It offers more in terms of lengths available, too, while requiring 6Nm of torque on the bolts, so it’s easier to fettle with while riding.

The Pembree GCS stem carries all of the hallmarks that you would expect of a Pembree product. It’s built to a high quality, and it does what it’s built to do incredibly well. Just be sure to have your bike set up properly before riding, and you shouldn’t run into problems with its high torque specifications. However, it is rather pricey.

You might also like:

Test report Pembree GCS stem review £130.00

Stems

Product purpose: 

Pembree says, “Developed for the most demanding riding, the GCS stem combines rigidity, precision, and reliability. Its wide clamping area maximizes handlebar grip for crisp handling, even on the most demanding terrain.” This is accurate.

Build extra: 

Material: 75% recycled aluminium

Clamp Diameter: 31.8mm, 35.0mm

Lengths: 35mm

Bolts: M6 Stainless Steel with washers

Stack: 40mm

Rise: 0°

Testing: EFBE Gravity Tri-Test

Made in: UK, assembled in France

Product construction 


Product construction extra: 

Excellent construction and build quality, but high torque ratings make things tricky.

Product performance 


Product performance extra: 

Great stiffness, but those torque ratings and the Loctite-coated bolts can make on-trail adjustments hard.

Product weight 


Product weight extra: 

It’s not the lightest but it’s by no means the heaviest.

product value 


All the deals displayed on our review pages are pulled from a constantly updating database feed of the best affiliate deals available. The criteria for deciding on what are the best deals is who is offering the lowest, delivered price. In most cases we will be showing the very best deal available online, but sometimes you may be able to find an item cheaper. If you can please feel free to post a link in the comments box below. To find out more about affiliate links on road.cc click here.

Product value extra: 

There are capable and well built stems around for less money, but they may not be EFBE certified.

Overall performance: 

It’s a great stem that does its job well. It can just be tricky to adjust.

Product likes: 

Looks, markings, build quality, stiffness.

Product dislikes: 

Price, loctited bolts and high torque specifications.

Enjoy: 

Yes

Buy: 

No

Recommend: 

If they keep on top of their pre-ride checks

Conclusion: 

It’s pretty, well-built, and effective, but on trail tweaks aren’t as straightforward as I would like.