Big suspension and big sine waves
Mike Levy at Pinkbike posted a must-read article:
The Argument For Short Travel Bikes – Opinion
Levy speaks a lot of truth. Here’s an additional thought:
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No matter what kind of bike you ride, you have to hop over huge rocks. That’s physically easier on a smaller bike with firmer suspension. 2010 Stumpjumper Pro Carbon with Brains front and rear. Check out Brains for braaap |
One of the keys to Riding (capital R) is the ability to load and unload in phase with the terrain. You erase impacts and create propulsion while separating your body from trail chaos. We call this skill “pump.” Pump is the key to increased control, smoothness and speed in all kinds of situations. It also improves your test scores and helps you attract a hot wife. It has for me, anyway.
In order to pump well, you must be able to connect very heavily with the ground then disconnect just as lightly. In other words, you need to create sine waves: light over frontsides and chaos; heavy on backsides, in corners and under braking.
If you want your bike and body to move in a certain direction, you need to push the Earth in the opposite direction.
Suspension mutes this connection, and the more suspension you have, the more vague the feel. Yes, the suspension insulates you from rocks, roots, holes, weakness, laziness and suckiness. But it also demands more range of motion, aggressiveness and strength to ride in phase with the terrain. On a DH bike, most mortals are likely to wallow in the travel — not feeling the hits but also never generating the sine wave they need to truly rip.
Smart suspension tuning can help you achieve that perfect blend of firmness and plushness that lets you pump when you want to and plow when you need to, but in general:
The more insulation you have from the terrain, the more insulation you have from truly ripping. Zero suspension rewards pump but punishes mistakes. Mega suspension erases mistakes but mutes pump.
Two kinds of bumps
Let’s boil every trail obstacle down to two kinds of bumps: 1) the little bumps you should ignore and 2) the big bumps you should pump.
The bigger your wheels and the longer your travel, the bigger the bumps you can ignore. You can process less intricate data and ride a bigger sine wave. That jagged outcropping? Ignore the details and treat it like one big roller. Light over the front, heavy down the back. Nice. That’s what suspension is for.
A downhill bike has eight to 10 inches of travel, but only in the most violent moments. Your arms and legs have 20 inches or more — and that travel is smart: You can unload before you hit bumps. Plus you can use your body travel whenever you want, not just when you bash into something.
So: Arms and legs are way better than suspension. But the more suspension you have, the harder it is to use your arms and legs.
Therein lies the compromise. Very few of us are aggressive or powerful enough to pump downhill or even all-mountain bikes. For most of us on most trails, the right amount of suspension is somewhere in the middle. We need a bike that’s smooth enough to absorb chatter, yet firm enough to pump.
I’m loving my 5-inch Stumpjumper 29 on trails I used to ride on the downhill bike.
 Not only does my 2012 Stumpjumper Expert Carbon with FOX 34 and Shimano XTR climb way better than a bigger bike, it’s more fun to ride at reasonable speed with reasonable effort. |
Downhill bikes are rad. They encourage us to see farther, ride faster, create bigger shapes and possibly achieve a higher level of flow — especially in truly gnarly terrain. All it takes is skill, strength and vision. But that’s another post.
 Smashing big sine waves on the big bike. My 2012 Demo 8, now with a FOX 40, rewards hard work with huge flow. |
Braaap! Keep it up Mike!
Lee
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Lee — I was hoping you’d put in your 2 cents on this. I thought it was interesting that Levy defined “short-travel” as 5″. Do you think that that is a clear dividing line? Ie, do you think there’s a pretty big jump from a 5″ bike to a 6″ bike (I know geometry has a big effect, too). Part of my interest is that for my next ride both the Stumpy evo (26″) and Enduro are on the short-list and I’m wondering how you think these two bikes fit into this discussion. It’s probably too dependent on rider skill/experience and the trails he/she’d be riding to generalize, but I thought I’d ask anyway 🙂
Thanks!
Allen
Hey Allen,
Yeah man, that’s a hard one to generalize. It seems like geometry tends to become more DH when you move from five to six inches of travel.
As you’re hinting at, the perfect bike for you depends on your strength, skill, confidence, terrain, riding buddies, goals, etc. and etc.
A skilled rider like Levy can handle a 5-inch bike on some pretty hairy terrain. For a long time, I rode my Demo 9 (then Demo 8) on our local gnar. Then I spent a few years on my Enduro. Now I’m riding the same stuff on a Stumpy 29.
As my skills increase, my desperation decreases and I focus more on Flow, I find I can have a great time on “less” bike.
BUT: I still love ripping huge sine waves on the Demo 8. While the trail bike will always be home to me, the big bike opens up my eyes and gets me used to bigger speed. Sort of like a DHer riding moto.
Thanks, Lee!
The article and comments are very interesting. While I was reading the article, it seemed most of the reasoning for using less travel came down to improving skill and being on a little bike is “more rewarding” (as he put it) when you do something difficult.
Then as I was reading your take on the article, I found it interesting you mention the bigger the wheel or longer travel, the more bumps you can ignore.
I thought these were the same arguments against a bigger wheel too.. Less skill is required, 26 is more fun, blah blah etc. etc. After having some time on your evo 29 do you think that article or reasoning should be used against the larger wheel as well?
I’m not against the newer wheel sizes and I am contemplating going from my stumpy evo 26 to a 150 travel 27.5 or 130 travel 29, but I really don’t want to regret a change.
From what I have seen around here in UT, people that have one bike seems to go toward the smaller wheel size unless they are XC riders and people that have a 120-130mm travel 29er also have a big bike. I am the type of guy that has one bike and I ride everything from XC to lift accessed to enduro races. If you were going to have one bike what would you personally ride?
All bikes are rad.
Big wheels and big suspension are neither good nor bad. They are tools that can be used in both lame and awesome ways.
My Stumpy 29 is a very good one bike.
“All bikes are rad.” True, but these days I can still at least somewhat afford to put together a decent short travel bike. Sadly, the industry seems hell bent on pricing everyone whose not incredibly affluent or have mortgages/rent/college loans/families to pay for, out of the DH market. That’s not rad in my book.
Yep …
I really, really love my Stumpy 29 Carbon/Roval Carbon/Fox 34/Shimano XTR wonder machine, but a bike that costs 30% as much can be 90% as fun.
A Specialized Status II has an MSRP of $3300 and is going to be a ton better than pretty much any DH bike from even a few years ago. Hope to see more bikes in this category.