|We're not famous for being quick to release products.|
- Ian Collins, Renthal
|The Apex - Renthal's New Stem Range|
Until now Renthal haven't offered a huge range of lengths in their stems. This has always seemed somewhat out of place for a company who offer their handlebars in four different rise heights, lock-on grips in four compounds and chainrings in 12 sizes. It turns out this has been something they have been looking to put right for some time now. When we visited their Manchester, UK, headquarters back in early 2012 we saw a prototype 70mm stem, but that development process is only now bringing new products to market. In the words of their marketing manager, Ian Collins, "We're not famous for being quick to release products."
Intended use: XC/trail/all-mountain/enduro
CNC machined 2014 aluminium body and 7075 aluminium clamps
+/- 6 degree rise
40-90mm length in 10mm increments
Weight: 118g-158g, dependent on length
31.8mm clamp only
1 1/8 steerer only
Available: Late July
With the Apex range they are upping their offering from just 40mm and 50mm lengths to 40mm all the way up to 90mm in 10mm increments. Ian explains, "In Europe, certainly in the Alps and in the UK, very few people run longer than a 70mm, with most at 50mm or less. However, we are a worldwide brand and elsewhere in the world there are a lot of people riding longer stems. We needed a design that could span all those different lengths."
We have been using their Duo stems for some time now and have nothing but good things to report about them, so the obvious question was: Why fix it, if it ain't broke? It turns out the problem is the extra length and the unique, two-piece split design of the Duo stem. Ian admits that the Duo stem "design doesn't lend itself to anything longer than 50mm. We made proto duo stems in longer lengths, but it became very heavy, because you had to add extra hardware to bolt the two pieces together, and it wasn't stiff enough. That's why we had to go for a one-piece body." At 50mm the weight of the Apex stem is 127g, versus the 143g for the Duo stem, there is very little in it. Yet once you extend the stem out to 70mm the Apex goes up to 140g, but the prototype Duo stems went up to around the 280g mark for an equally stiff stem. At 90mm these calculations are exaggerated even further.
To extend the stem, they had to switch to a one-piece body, but then set about improving the design to remove every excess gram from the design. The most obvious thing people will notice is that missing material between the clamps, which they realised wasn't needed - in fact this style of design was taken over to the prototype DH stems you see many of the Renthal-sponsored World Cup racers running right now. Less obvious is the refinement to the clamp design. Ian says they saw big benefits with this design, "The clamp is very different from what other people do, it has 240 degrees wrap of the clamp. By making the clamp like that, you move the stem bolt outboard further, without adding an more material. By doing that you can also run a much bigger bore down the centre [to remove more unneeded material from the interior]. This means you can make the stem more over-sized with a bigger outside diameter, which means you can make it stiffer but keep the weight right down. The other reason is that you have pulled the stem body material backwards, and the stem body is the heaviest bit, the clamps are light, so more of the length is made up of the clamp which brings the weight down."
With the extended lengths, they had to reduce the rise of the stem, from 10 degrees to 6 degrees. At 50mm the difference is minimal, but with a 90mm stem, 4 extra degrees of rise make for an unwieldy cockpit. With the increasing popularity of big-wheeled bikes, the new stem also reverses to offer 6 degrees of drop, rather than rise. While you can flip any stem, the Renthal is designed to look good both way - you just need to flip the clamps over to keep the marked lower part of the clamp at the bottom.
One thing that people have commented on with the Duo stem is that some people have problems with creaking as you do need to install them correctly - we never had a problem with this, but have seen several people report it in the comments. With the new system that issue is gone with a much simpler assembly process. The lower part of the clamp is tightened first to sit flush against the bar, which Renthal say is better for distributing force through your bars, then tighten the upper part to hold the bar in place.
Ian did stress that the Duo stem is in no way obsolete and will be continued at the same price point as the Apex stem. He was reluctant to draw clear lines in the sand for where the crossover between the Duo and the lighter Apex stem is. The line seems to be that if you're racing the Enduro World Series you will probably want the Apex stem, but if you're going hucking at the Rampage site, the Duo stem is a better bet. We're not sure how much market there is for freeride-specific stems these days, so suspect most riders would opt for the new Apex design, but Renthal say that as long as there is demand for the Duo stem, they will keep making them.www.renthal.com