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I’ve been riding for 40+ years of which the last 25 I’ve ridden Specialized. Around April last year I decided to replace my old bike with a brand new Sirrus Sport, on an XL frame. While I love the looks and riding it, I have a serious safety concern. It has happened now multiple times that when I make a turn at a relatively high speed, the pedal hits the ground scaring the hell out of me. While this has happened in the past with other bikes, it has never happened to me this frequent, to the point that I don’t feel safe riding and turning at high speeds and that of course impacts my overall performance.

I wonder if anyone has had the same experience with my exact same bike model. Could this be a Specialized design issue...? or could it be that whoever assembled the bike used the wrong stems or pedals...?I've got some pictures of the damaged pedals:

enter image description here enter image description here enter image description here enter image description here

I’d appreciate your feedback, or comments regarding how to fix this. I've contacted the place I bought the bike twice but I'm not getting an answer, perhaps I should try Specialized directly.

Glenn Stevens
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Bruno Antoniano
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    It's the shape of the bike -- the height of the bottom bracket and the length of the cranks. But note that many cyclists (like myself) do not pedal through a sharp turn but put the outside foot down. – Daniel R Hicks Apr 08 '15 at 03:25
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    (A second reason for not pedaling through turns is to avoid "toe strikes" where the toe hits the front wheel. Or, on a loaded tourer, where the toe hits a front pannier.) – Daniel R Hicks Apr 08 '15 at 11:59
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    There's no designer's fault in this, you generally should avoid cornering with your inside foot down. At high speeds you lean inside the corner and depending on your speed and bike setup, it may happen on every bike with an inside foot down. Probably your new bike is slightly lower/has longer/thicker pedals and what was acceptable on your old bike, requires changes in technique on a new one. – Slovakov Apr 09 '15 at 10:08
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    The only people who should be pedalling through tight corners are crit racers, and they ride bikes with short cranks and raised BBs. – Qwerky Apr 29 '15 at 08:47
  • This is a design flaw, and a very serious one. There is no reason to stop pedaling just cause you are turning. – Raj More Jul 01 '16 at 16:43
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    @RajMore No, it's a user flaw. Daniel R Hicks and Slovakov have already explained why one shouldn't pedal through corners. The fact that the pedals hit the ground is the reason to stop pedalling!! – David Richerby Nov 30 '16 at 09:06
  • Have same pedals and exactly the same problem. The funny thing it is only in one side. I believe that they are quite wide pedals in addition to that you should rise the pedal at the side you are turning this will make it easier and also will avoid you hitting the ground. – kifli Nov 30 '16 at 10:52
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    @kifli how sloped is the road ? Could be turning one way gives you less space because of the camber of the road topping. – Pete Nov 30 '16 at 11:04
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    @Pete no the roads I use are totally flat and in a good shape. My bet is on that pedals are big and have this square shape if you look at flats for mountain bike they have this rhomb shape. In the photo the impacts were taken on corners of the pedals. – kifli Nov 30 '16 at 11:50
  • @DavidRicherby I guess this is a difference between cornering with motorcycles and cornering with bicycles. On a motorcycle, especially on a racetrack, you accelerate out of a corner starting just around the the apex - the exact spot depends on your riding style. I guess while the principle of counter-steering is the same, the acceleration out of a corner doesn't kick in until the bike is much more upright. – Raj More Nov 30 '16 at 15:21
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    @kifli and bruno you could try trimming the ends of your pedals using diagonal cutters or sidecutters or a hacksaw. Anything outboard-side from the end of the axle is not structural. The road will rub these bits of plastic off over time anyway. – Pete Dec 02 '16 at 23:56

4 Answers4

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Cornering at slow speeds is easy. Cornering fast, that's where it starts getting harder.

You're getting pedal strike because your pedal is lower than the road surface, so consider not pedaling through the faster corners.

Instead, put your outside pedal down and put your weight on that leg. IE, for a left turn you should be pressing on your right leg. At the same time, unweight your saddle a little, a lot, or completely.

This does dual purpose of pressing the tyre's shoulder into the ground for more grip and less slide, and in your case keeps the pedal clear of the ground.

From http://blog.artscyclery.com/technique/mountain-bike-cornering-skills-the-fundamentals/

http://blog.artscyclery.com/wp-content/uploads/2013/02/cornering-620x350.png

You can see how this chap has an exaggerated body position above the center-line of the bike.

From http://www.stickybottle.com/coaching/coaching-how-to-corner-fastest-when-racing-and-how-to-save-energy-in-sportives/ A more road-bike photo. Rider is not pedaling.

http://www.stickybottle.com/wp-content/uploads/2013/02/fintan-ryan-cornering.jpg

From http://www.bikeroar.com/tips/finding-flow-perfect-your-mountain-bike-cornering-technique Again a slightly artificial photo, but it shows clearly the weighting on the outside pedal as well as looking right ready for the right turn.

enter image description here

Criggie
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    This is absolutely the right answer. You should not be pedalling all through tight, fast turns. – fgysin Nov 30 '16 at 10:48
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    In the last pic the rider is not only ready, but he is turning. His CG is a long way from the wheel contact point. Good pics. – andy256 Nov 30 '16 at 12:32
  • Btw, although the pics show more MTBs than road bikes, the technique shown is definitely applicable to road bikes. Nice answer Criggie. – andy256 Nov 30 '16 at 12:35
  • @andy256 yes I was looking for pictures that showed clearly the point. Almost all were MTB or off-road, possibly because road riding is more fine adjustments and MTB is much more coarse being at lower speeds. – Criggie Nov 30 '16 at 19:58
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    @Criggie the reason you see far more MTB examples is because its a more important technique on MTB. On tarmac you have loads of predictable grip, so can get away with all sorts, off road on mixed surfaces, you need to get technique right to find grip and carry momentum better. – Andy P Dec 01 '16 at 15:37
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It's definitely possible that the bottom bracket height is lower than your previous bike and/or your crankarm length is longer.

The BB could be lower to improve handling and I have definitely seen longer crankarms on large bikes. A typical measurement is 175cm but you could see 170 on a small frame or 180 on a larger frame. The longer crankarm would be to accommodate your longer legs.

Look on the inside of the crankarm, you should see the length stamped in there, or you could measure from the center of the bottom bracket to the center of the hole where the pedals are.

I don't think it's an inherent design issue but it could be a different design that doesn't work well with your riding style.

Side note: When cornering hard if you are going to have a foot down, you want your outside foot down. This lets you keep your weight over the tires for maximum traction. If you really want to continue to corner hard and fast you could ride hard in, drop the outside pedal, corner hard and then standup out of the corner and hammer on!

But, back to your original question, if you want to try and track down the issue, I would measure the bottom bracket height and look for/measure the crankarm length. One or both of those measurements compared to your old bike would give you some insight.

JamesG
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    Thanks James. The old bike does have the number 175, while the new one only has a 17. But I did measure the crankarm lengths and the old one is 7 inches versus the new one at 7.5 inches, so that's a considerable difference: .5 inches or 1.27 cm... interestingly though the size of te pedal in the old one is 4 inches long versus 3.5 on the new one. The distance from the pedal to the ground is the same on both. I'm going to replace the crankarm with a 7 inch one and see if that solves the issue. – Bruno Antoniano Apr 08 '15 at 00:41
  • @BrunoAntoniano - The critical number is the distance from the pedal to the ground, when the pedal is at the bottom of the stroke. This is the BB height minus the crank arm length. – Daniel R Hicks Apr 08 '15 at 12:01
  • Agree with this, but also with Ehryk's answer. You may consider measuring the width of your old pedals vs the width of your new pedal. A narrower pedal (from crankarm to outside edge) may also reduce your incident of pedal strikes. – Deleted User Apr 08 '15 at 16:27
  • 175cm -- that's a long crank! – David Richerby Nov 30 '16 at 09:08
  • @BrunoAntoniano You seem to be claiming that your new 175mm cranks are 12.7mm longer than your old 170mm cranks. – David Richerby Nov 30 '16 at 09:13
  • Remember, the length of the crank isn't important as what's important is the distance between the bottom bracket and pedal axels. – whatsisname Nov 30 '16 at 22:12
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Would you consider clipless pedals instead of clipped platform? This is probably the most turning clearance for the dollar, second to replacing the crank arms with shorter ones.

A set of these pedals will improve your power output as you can pull harder on the upstrokes, as well as shaving probably ~1" or more off your pedal clearance.

Clipless Pedal

One downside is that they are terrible to ride on without shoes designed to clip in, though some types (like SPD) have shoes with the clipless hardware recessed into the sole for easier walking.

Ehryk
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  • Yeah, not a bad idea, thanks. Can you recommend a set of SPD I could wear with a regular set of walking/running shoes...? – Bruno Antoniano Apr 08 '15 at 22:08
  • @BrunoAntoniano I have a set of Shimano A530's that I like a lot. http://www.amazon.com/Shimano-A530-SPD-Pedals/dp/B00AAOIAQC You would use cycling shoes with cleats on one side and you could use regular shoes on the flat side. – JamesG Apr 20 '15 at 22:23
  • So now his shoe will bottom out, possibly injuring the outside edge of the foot. – Kaz Nov 22 '16 at 22:51
  • Maybe it will, but it will have easily an inch of additional clearance. – Ehryk Nov 22 '16 at 22:58
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Three options - or combination

  • coast through the turn with pedals horizontal to the ground
  • more narrow pedal
  • shorter crank arm
paparazzo
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