Have you ever wondered if reaching for the lockout lever is worthwhile? Sure, a firm lockout can make a bike feel
more efficient, but does this really translate into faster climbing? And if so, how much faster can you go for the same effort?
To find out, I've ridden up the same climb way too many times, using a power meter and a stopwatch to try and find some answers. To control variables and keep things repeatable enough to measure this in the real world, I picked a short road climb with 44m of elevation gain and a nice consistent gradient.
The short climb made it possible to do lots of timed runs so I could see if my times were consistently faster with the lockout on or off - if you only do a couple of timed runs you can never know if you would have gone faster anyway.
The climb's consistent gradient is important because changing gear or effort mid-climb can make it harder to stay consistent between runs. I picked a day with barely any wind and kept the same position so changes in aerodynamic drag didn't affect the results. I measured my time and average power output over a marked section of the climb, and aimed for smooth, efficient pedaling at a cadence of around 80 rpm, trying to keep as close as possible to a 315 watt power output. I did a total of twelve timed runs over two bikes, alternating between riding with the lockout on and off.
I rode eight runs on a Privateer 161
(four with the lockout on and four with it off), then I did four more runs (two on, two off) on a Geometron G1.
The 161 has 161mm of rear wheel travel and 120% anti-squat at sag, making it an efficient peddler, but the RockShox SuperDeluxe shock has a light damping tune which allows some bob when open. The firm lockout virtually eliminates bob when closed, which should increase the difference I'm trying to measure. The Geometron G1 was set with 175mm of rear travel and an EXT Storia Lok shock. This bike has around 100% anti-squat, and bobs noticeably more than the Privateer when fully open. Anti-squat
values are calculated with an arbitrary center of mass height, so because I'm tall I need more than 100% anti-squat to minimize pedal bob.
It's not easy to hit the exact same power output every run; sometimes my average power was a few watts above or below the 315 watt target. Fortunately, it's easy to compensate for this using math. Climbing speed is, to a very good approximation, proportional to power output on a steep climb (I've checked this by riding the same climb at different power), so it's easy to work out a very good estimate of what the times would have been if each one was done with exactly 315 watt. Results
On the Privateer, the average time of the four runs with the lockout off was 3:14.7, while the average of four runs with lockout on was 3:13.9. That works out to 0.4% quicker when locked-out. Meanwhile, the G1 was on average 0.8% faster with its lockout on.
Looking at all the results from both bikes together, there is a statistically significant
difference between the times with the lockout on vs off. In other words, I was consistently
faster with the lockout on, and it's unlikely that would happen by chance if the lockout wasn't having an effect.So using a lockout is faster, but is it a big deal?
Based on this, over an hour-long road climb you'd save 14.4 seconds by using the lockout on the Privateer and 28.8 seconds on the G1. That's not going to make a huge difference to most of us, but if you're at the sharp end of an XC-marathon race, or running late on an EWS liaison, that kind of time could be worth a lot to you.
Put another way, the time taken to dispatch a steep and simple climb is more-or-less proportional to the total weight of the bike plus rider; so if you have a combined weight of 100kg you'd need to save 400g from the Privateer, or 800g from the G1, to make the same difference. To me, this says more about the effectiveness of saving a few hundred grams than it does about the effectiveness of a lockout.
On the other hand, if it takes two seconds to lock and unlock your shock, you'll need to be climbing for about eight minutes before you recoup that time on the Privateer.What's the bottom line?
In a nutshell, the advantage offered by a lockout under these conditions is measurable but modest. It's safe to assume though that when riding out of the saddle, pedaling with poorer technique, or riding a bike with less anti-squat, it will be more pronounced - possibly a lot more. So the results here are probably the lower bound of the effectiveness of a lockout (on an enduro bike). Measuring the difference when out of the saddle might be trickier though, because it's harder to do consistently.
It's worth acknowledging that on a steep and smooth climb the main advantage of a lockout might be the steeper dynamic geometry and the more comfortable position this provides, so any increase in speed may be considered a bonus.
The effect of a lockout on a rough climb is a separate question. I'd be interested to see how rough the surface needs to be before the lockout is no longer an advantage, and if it makes climbing slower at some point. Perhaps I'll do a part two to find out.
Let us know in the comments if this is something you'd like us to investigate further.