In his recent post
Exploring the Relationship Between Handlebar vs Stem Length, Richard Cunningham proposes that handlebars and stems interact to create effective stem lengths — and that there is a sweet spot in terms of effective stem length.
In this post I hope to expand the discussion and give you something helpful to think about. Here goes:
Steering-Hands Offset (SHO) is the distance of your hands in front or or behind your bike’s steering axis.
In the above diagram, the mostly vertical line is your steering axis. This line passes through the fork’s steerer tube, through your headset cap and into outer space. The aliens have noticed a gradual slackening of this line.
The horizontal line runs from the steering axis to the midpoint of the grips. This distance is SHO.
Your favorite SHO (if you have one) is determined by your riding style, personal preference or (most likely) what you’re accustomed to riding. If you have a favorite handlebar/stem combo, you probably like the SHO they create.
We humans can ride a wide range of setups, from 150mm XC stems (like I rode back in the day) to direct-mount downhill stems. We are very adaptable.
That said, your bike’s SHO affects your riding. Here are some general notions:
Positive SHOWhen your hands are in front of your steering axis, you have positive SHO. This Specialized Epic has a very positive SHO.
When you have positive SHO:
When you steer from one side to the other, your bars arc away from you, then they arc toward you. This is very pronounced on a road bike.
When you lean or push forward on the bar, your bike wants to go straight. This adds stability for riders who ride with weight on their hands. For many riders, this feels familiar and comforting.
Negative SHOWhen your hands are behind the steering axis, you have negative SHO. This Mondraker Dune has a very negative SHO.
When you have negative SHO:
When you steer from one side to the other, your bars arc toward you, then they arc away from you.
When you lean or pull backward on the bar, your bike wants to go straight. This adds stability for riders who lean back on their bikes. For many riders, this feels unfamiliar and odd.
Neutral SHOWhen your hands are in line with the steering axis, you have neutral SHO. This Specialized Stumpjumper has a neutral SHO.
When you have neutral SHO:
When you steer from one side to the other, your bars follow a simple arc, like a steering wheel.
Your bike handles the same whether you’re pulling or pushing the bars. It handles well in general. It just feels good.
I’ll bet you’ll like a SHO in the 0-20mm range, and the closer you get to zero the yummier your bike will feel. You might not agree, but it’s fun to think about — and maybe you'll enjoy disagreeing. Let me know what you think in the comments below.
Learn more about SHO and other aspects of mountain bike setup in the book
Dialed and at
www.llbmtb.com. The website includes online calculators that help you model various frame, bar and stem combos — and make sure they fit before you spend money.
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I’m Lee, and I Like Bikes. Over the years I’ve written 10 mountain bike books, built a bunch of pump tracks, taught thousands of riders, invented RipRow and devised the RideLogic bike setup system. Thanks to the knowledge I’ve discovered for the mountain bike community, I’m riding better — and having more fun — than ever.
Learn more at
www.leelikesbikes.comwww.llbmtb.comwww.riprow.com
Secondly, the more freeride the bike, the greater the RAAD angle, from my race bike, fixed gear, XC to FS. That made sense.
Of course, the way my bikes achieved these numbers was the thing that did not fit modern thinking. Particularly, I had long wondered what sense the 11cm strem of my XC bike, or 9cm of my FS - with their wandering steering on steep climbs? Zero SHO would surely be the last piece of the puzzle!
I quickly got the new 29er frame - a carbon hardtail - from its box to measure: Longer effective top tube - Check! Steeper seat tube angle - Check! RAD with short enough stem to achieve zero SHO? It does look like it. A bit sigh of relief!
I am really looking forward to getting this new bike built up!
www.pinkbike.com/news/exploring-the-relationship-between-handlebar-vs-stem-length.html,
which judgementally indicates that one way is right and the other is wrong.
What effective stem length or, steerer-hands offset, is right for you - negative, zero, or positive?