Bike Stiffness. How To Tell?
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Bike Stiffness. How To Tell?
There is much talk about Bike Stiffness. When I am trying a bike, or riding a bike, how can I tell how stiff it is?
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you're likely not strong enough for it to matter.
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You can't. It is subjective, and has no unit of measure.
By the way, the more items that you compare before making a purchase, the more likely you are to be dissatisfied with your eventual choice.
By the way, the more items that you compare before making a purchase, the more likely you are to be dissatisfied with your eventual choice.
#6
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A friend of mine once remarked the thing he liked most about his bike was also the thing he hated the most, something like stiffness is great for races requiring quick accelerations, but it's not so good on those 3+ hour rides.
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Stand on one side of the bike, one hand on the bar and one on the saddle. Lean it away from you a bit and with the pedal in the down position press on it and note how far the BB shell moves off the CL. Maybe run string from axle to axle first as a gauge.
(Bikeshop bros are gonna love me for this.)
(Bikeshop bros are gonna love me for this.)
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The responses seem to assume a bike can't be too stiff. Not so. For example, touring bikes often feel dead when not loaded, disproportionate with the weight. Some racing style bikes also feel dead and unresponsive after an hour or so, in spite of light weight.
Super stiff often feels alluring and responsive in the parking lot, but it can really suck out on the open road. Your legs turn to lead and you struggle to stay on top of your gear where another bike may still feel eager to go even when you are dead tired.
On metal bikes (carbon bikes are too small for me), I look for some springiness when twisting between the bars and seat tube, but if it has an exaggerated shivering that stems from my nervous unfamiliarity, it is probably too flexy. I also look for a small amount of frame springiness when pressing on one pedal with the brakes locked (about as hard as I would under hard seated riding), but not to where it feels sloppy. The movement should feel linear in relation to force. If it feels dead stiff in every direction, it won't work for me.
Unfortunately, those tests are subjective and require personal experience.
Super stiff often feels alluring and responsive in the parking lot, but it can really suck out on the open road. Your legs turn to lead and you struggle to stay on top of your gear where another bike may still feel eager to go even when you are dead tired.
On metal bikes (carbon bikes are too small for me), I look for some springiness when twisting between the bars and seat tube, but if it has an exaggerated shivering that stems from my nervous unfamiliarity, it is probably too flexy. I also look for a small amount of frame springiness when pressing on one pedal with the brakes locked (about as hard as I would under hard seated riding), but not to where it feels sloppy. The movement should feel linear in relation to force. If it feels dead stiff in every direction, it won't work for me.
Unfortunately, those tests are subjective and require personal experience.
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Stand on one side of the bike, one hand on the bar and one on the saddle. Lean it away from you a bit and with the pedal in the down position press on it and note how far the BB shell moves off the CL. Maybe run string from axle to axle first as a gauge.
(Bikeshop bros are gonna love me for this.)
(Bikeshop bros are gonna love me for this.)
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"Stiffness" in a bike is difficult to quantify, and its benefit, or lack thereof, varies depending on the rider and where you ride. Heavy riders benefit most from a very stiff bike. Light riders suffer on stiff bikes, particularly on rough surfaces. At 145#, I find stiff bikes difficult to control on rough pavement.
So, don't take "stiffness" as the single arbiter of a good bike. Ride what works best for you, and let the marketing department worry about "stiffness."
So, don't take "stiffness" as the single arbiter of a good bike. Ride what works best for you, and let the marketing department worry about "stiffness."
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Or your avatar, it could be your avatar.
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Doesn't Park Tools have a stiffometer? Maybe go down to the local co-op and ask to borrow theirs.
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Ride em. In the case of my now relatively old SL2 Roubaix frame, I did not appreciate how not "stiff" is until I rode my LeMond. As mentioned above, a hill will help you tell the difference.
#20
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I wash my bikes in a special Viagra/detergent mix for extra stiffness.
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If you pedal hard while standing and your arms want to come off it means you've got a stiffy
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One interesting thing I have discovered with very flexy carbon fork I had on my old bike was when using a magnet style speedo sensor the speed would drop when I did out of the saddle sprints due to the bowing of the frame.
I am curious if using a speed and cadence sensor can be used to determine flex by placing it in different locations on seat and chain stays.
I am curious if using a speed and cadence sensor can be used to determine flex by placing it in different locations on seat and chain stays.
Last edited by VwFix; 11-08-15 at 04:30 PM.
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