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Home » Cycling » The Importance of a Good Road Bike Frame in Relation to Speed;  A Stiff Frame is Great to Find, Kinda…

The Importance of a Good Road Bike Frame in Relation to Speed;  A Stiff Frame is Great to Find, Kinda…

February 2017
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I’ve written a lot of posts about my road bikes.  About the upgrades, the order of importance I placed on those upgrades, and the pieces of the puzzle that I was happiest to spend a ridiculous amount of money on.  What I haven’t written about, I think ever, was one of the final contributing factors that really sealed the deal for my purchase of a Specialized Venge Comp.  If I remember the review correctly, they suggested that, for the money ($3,100 at the time), you couldn’t go wrong because even if you took all of the pieces and parts off, you still end up with a world class frame for Three Grand.  I liked that “world class” bit.  Put in perspective, a Pinarello F8 frame starts at Five Grand.  How about a Time Izon?  $3,200.  A Bianchi Infinito?  $3,700  See where this is going?  I got a whole bike for less – and a couple of the top sprinters on the Champs Elysees were riding that frame (though with better carbon fiber – 11r for theirs, 10r for mine, but I need that extra “r” like I need a hit in the head):

Eventually I’ll pony up for a really nice set of carbon clincher wheels but I’m not holding my breath.  My wife isn’t either.

That out of the way, I was reading a post a while back that had me beside myself that I’d missed something so blatantly obvious in all of my musings about what I’d learned over the last several years of cycling that I had to give it some mention.

The author’s bicycle “order of importance” list, pertaining to the parts on his bicycle that are most important to his racing, had the bike frame first and the wheels, amazingly, were down toward the bottom of his list.  Wheels were toward the top of my list and the frame didn’t even make the list.

In thinking my cycling experience through, I never even thought about the importance of a good frame because all the while I’ve been riding on two world-class frames.  I’ve never really ridden a bad frame.  In other words, I’ve had a blind spot – in assuming that a frame was a frame.

With equal wheels (actually with the same wheels), riding in a group, there is little difference between the two bikes shown above.  I do have to work just a little harder on the Trek, but I can ride it just as fast and just as far as I can the Venge.  The difference is noticeable but not extreme… until we start talking about sprinting.

Where the two frames part company is during sprints.  I can launch the Venge.  That’s the best way to put it.  When I get out of the saddle and triple my power output in two pedal strokes, the bike shoots forward.  On the Trek I simply can’t duplicate the results I get on the Venge.  We’re talking on the order of 3-5mph slower in a sprint and there’s a lag in the surge of the bike when the power is put down as well.  This is a problem with the frame (all of the components and bearings are in good working order)

The lag and flex of the frame is so bad, depending on the company I’m keeping, I’ll change roles from sprint to lead out if I’m on the the 5200.  I simply can’t put down enough power to overcome the flex in the frame.  I’ve written about this difference in frames before but never expanded on the idea because, truth be told and not to put too fine a point on it, I was ignorant.

The Trek 5200 was a gold-standard race frame from the late ’90’s and early 2000’s but it can’t hold a candle to my modern Venge frame, at least in a sprint.

Thinking about this in terms of my own ignorance, having never ridden on an inferior frame, I have to concede to the idea that the frame choice, for those who are contemplating getting into racing or even contesting City Limits signs on a club ride, matters.

The problem facing manufacturers has been making the frame compliant enough to dampen road vibration and bumps while being stiff enough to take immense force on the crank arms at acceleration.  Add to that, weight and it gets tricky.

Interestingly, my wife rides a brilliant Specialized Alias.  I’ve had occasion to test it for her a few times (my wife is only a few inches shorter than I am) and can tell you, without doubt, her bike is considerably better at smoothing out rough roads.  “Vastly” might actually be a better word than “considerably”, it’s that good.

Where this gets interesting is that a bike that is smooth on something like chip-seal asphalt will improve overall power output over the long haul.  Having ridden an ultra-stiff Cannondale SR-400 aluminum racing frame that transferred the vibration of rolling over a pebble a little larger than a grain of sand straight to the legs and kiester, rolling over chip-seal roads was demoralizing.  Trying to keep the power to the crank while being jarred was no fun.  I did it, but it sucked.  Going from that bike to my Trek 5200 was like switching from riding a jackhammer to Harry Potter’s Firebolt.  I actually paid attention to certain sections of my ride routes that had me gritting my teeth on the Cannondale… on the 5200 I was two miles an hour faster with the same effort.  My overall speed improved by almost a mile an hour (as tracked by Endomondo).

This gets really fun when the Venge is thrown in though.  I’ve already stated that the frame is stiffer which makes it a better bike for sprinting, right?  Well the Venge is also slightly more compliant than the 5200 when it comes to road chatter too.  I don’t know how Specialized did it but they did.  The Venge is compliant where it needs to be and stiff everywhere else.

That said, once I’ve floated all of that, what advice could I give about choosing the right frame for someone else?

This is my conundrum.  I simply don’t have anything.  I got lucky.  The bike I fell in love with in the display just happened to be exactly the right bike for me.  That said, I do have resources, so I’ll get to work on coming up with something.

To be continued…

By the way, as a side note, there will be those who will suggest that installing extra-wide tires, say 28’s or 32’s, and using lower tire pressure will lessen the harshness of the ride.  This is absolutely true.  On the other hand, everything you gain will work against you in a sprint (equal and opposite reaction and all – when you push down on the back as you’re lifting on the handlebar, that rear tire is going to flex under the pressure).  Not only that, those big tires won’t fit on most road bikes anyway.  My Venge is limited to a 25 or 26 mm tire (I run, currently, 24’s).

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6 Comments

  1. Bobo says:

    I like your blog, and I wanted to say that you remind me of a guy I used to work for.
    He would never use the phrase “my car”, it was always “my Corvette” for everything.
    For example, he would say “I left my keys in my Corvette”, or “my Corvette is in the shop”, or “I am going to wash my Corvette today.”
    He made sure everyone knew HE owned a Corvette.
    You’re kind of like that with your VENGE, aten’t you?

    • bgddyjim says:

      Nope, just a way to differentiate between my two road bikes. I call my 3700 my 3700 and that’s about the equivalent of an old Chevy Cavalier. The fact that I own a Venge isn’t really all that big a deal. I do love it though. It’s very fun to ride. I’m glad you like my blog though. Thanks.

  2. Are you on the 24mm Specialized Turbo tyres?

    My alloy race frame is super stiff and responds well to my attempts at sprinting, but damn it’s a harsh ride over some of Tassie’s rougher road surfaces! Carbon definitely takes the sting out of that (my TT bike feels so much more comfortable) but good tyres make a massive difference too.

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