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-   Clydesdales/Athenas (200+ lb / 91+ kg) (http://www.bikeforums.net/clydesdales-athenas-200-lb-91-kg/)
-   -   Clydes and pedal strengh (http://www.bikeforums.net/clydesdales-athenas-200-lb-91-kg/784577-clydes-pedal-strengh.html)

Pistard 12-01-11 12:21 PM

Clydes and pedal strengh
 
Just wondering, I am currently riding some clip pedals on my Hybrid, have a set of Shimano SPD sl pedals for my road bike, I was thinking the other day while going up a hill standing on my pedals "jee I wonder if i could snap them..." I am 218 lbs and remember a snapped pedal once as a teenager... I have recently been on blood thinners and started to think about taking a spill etc, bleeding is very bad for me...!

Seattle Forrest 12-01-11 12:35 PM

What's the weight limit on your pedals? I doubt this happens very often, but, I know that some ultra-light road pedals have weight limits that exclude Clydes, but mostly because they've shed so much material to keep the weight down.

CACycling 12-01-11 12:57 PM

I'm a bit heavier than you and have been riding SPD-SLs (105s) for a few years now with no problems.

dcrowell 12-01-11 01:23 PM

Unless you have cheap crappy pedals, or expensive weight-weenie ones, you'll be fine.

Nightshade 12-01-11 02:00 PM

Quote:

Originally Posted by Pistard (Post 13551796)
Just wondering, I am currently riding some clip pedals on my Hybrid, have a set of Shimano SPD sl pedals for my road bike, I was thinking the other day while going up a hill standing on my pedals "jee I wonder if i could snap them..." I am 218 lbs and remember a snapped pedal once as a teenager... I have recently been on blood thinners and started to think about taking a spill etc, bleeding is very bad for me...!

The weakest point for pedals is at the joint where they screw into the crank.

That hole is THE weak point in the whole crank set up.

I've seen the whole top (bottom) of the crank hole blown completely away from standing up on the pedals. I've never seen , or known of, a pedal stem breaking.

gyozadude 12-01-11 02:05 PM

The Shimano SPDs usually have a tapered cr-mo axle that is fairly sturdy. It weighs quite a few grams more than the axles on my Suntour XC Pro and Suntour Superbe Pro pedals, and the inboard bearing is closer to the crank than the Suntour pedals by half the distance. So the shearing stresses on the axles should be only half.

I rode the XC Pro pedals for 23 years before catastrophic failure on the left pedal axle. And it broke right at the face of the inboard bearing, where apparently, it looks like there was a defect in the hollow-axle extrusion. I've never broken any other pedals in over 30 years. And I've been at least 50 lbs heavier than you for most of those years and honking up hills all the time. And the XC Pro were the pedals I used a lot in off-road. So I doubt you're even close to any fatigue limit on your SPDs.

pdlamb 12-01-11 04:00 PM

Stay with steel (stainless?) pedal shafts, and you should be fine. I think the pedals with weight limits have titanium shafts.

Bomccorkle 12-01-11 04:06 PM

Stainless is softer than cro-moly.

Bomccorkle 12-01-11 04:15 PM

Actually 4340 forging is the strongest, the 4340 then mild steel then stainless and if your into exotics kryptonite is the strongest but I don't thing they use that for bikes.

Seattle Forrest 12-01-11 04:44 PM

They don't use kryptonite for bikes because some riders lose all their strength when they come near this material, like what happens if you put a retrogrouch on a carbon fiber road frame. ;)

http://img1.etsystatic.com/il_fullxfull.236596921.jpg

CliftonGK1 12-01-11 11:48 PM

Quote:

Originally Posted by Pistard (Post 13551796)
Just wondering, I am currently riding some clip pedals on my Hybrid, have a set of Shimano SPD sl pedals for my road bike, I was thinking the other day while going up a hill standing on my pedals "jee I wonder if i could snap them..." I am 218 lbs and remember a snapped pedal once as a teenager... I have recently been on blood thinners and started to think about taking a spill etc, bleeding is very bad for me...!

I'm not that much lighter than you (and I've been significantly more than your current weight). I hammer on a couple pairs of Nashbar house-brand SPD pedals and a pair of Shimano XTR pedals on my monstercross racing bike. I put some extra oomph behind my pedaling since I ride a lot of hills and all my bikes are singlespeeds.
Never snapped a crankarm or a pedal axle. Only time I broke a pedal was in a wipeout, and it was one of the cleat latches that broke off.

CraigB 12-02-11 07:13 AM

I suppose anything can break, but if it does, it'll be from a manufacturing defect and not your mere 218 pounds. Riding a bike in a cape, however, is just plain dangerous.

sstorkel 12-02-11 10:39 AM

Seems like there are quite a few people here confusing the OP's SPD-SL road pedals with the more solidly build SPD mountain bike pedals... In any event, I took a quick look at the docs for Shimano's Dura-Ace 7900 SPD-SL pedals and didn't see any mention of weight limits, so I wouldn't be terribly concerned about any of the SPD-SL pedals.

Pinyon 12-03-11 12:42 PM

I've broken a pair of Shimano road pedals. But I think it was really due to slamming into a curb during a wreck a few weeks before that.

Pedals are really hard to break. You are more likely to wear-out the bearings on a cheap pair, than to break the axle.

bigfred 12-03-11 01:16 PM

Riding at weights from 235-295 lbs over the last 25 years, the only catastrophic spindle failure I've suffered was on a pair of mid 80's Campy Super Records that had too light an axle. Like others have stated stay away from the super cheap and super light and you'll be fine.


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