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General Category >> Technical >> Broken Pedals, again
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Message started by Opus the Poet on Jun 20^th, 2009, 11:24pm

Title: Broken Pedals, again
Post by Opus the Poet on Jun 20^th, 2009, 11:24pm

I keep breaking pedals, as in putting power into them end they stop working and parts fall off breaking. I'm trying to rind at higher cadences in the 80-100 range and my average speeds have been in the 11 MPH range riding in mostly a 51" gear on flat or false flat roads but with lots of stop signs and traffic lights. so far I have crushed one bearing, which might have been a manufacturing defect, and broken the cages off twice now. I re-threaded the pedal body and put the cages back on again.

Am I dealing with bad pedals? I don't think my power output is the cause for this, or I would be doing a much higher average, because my cruise speed has been in the 15 MPH range. Yes, I'm slow [smiley=deadhorsebeat.gif] but I get there eventually. [smiley=rolleyes.gif] If I am breaking pedals because of the power I am generating I can't wait to see the times I run on the drag race trike I'm building [smiley=dbanana.gif]

Title: Re: Broken Pedals, again
Post by FlyingLaZBoy on Jun 21^st, 2009, 6:56am

I'm guessing it's faulty pedals... It's never happened to me, and I doubt even Mark Hastings carting 80 pounds of groceries on his Xtracycle is having pedals break on him... Mark?

Title: Re: Broken Pedals, again
Post by power_bent on Jun 21^st, 2009, 12:39pm

I've been on two bike tours with a combo of 420 lbs and climbing hills and haven't broke a pedal. I might say that it could have been faulty pedal. What kind are you using??
P.S. i have the pedal extender on the last run.
Later Thomas J [smiley=dbanana.gif]

Title: Re: Broken Pedals, again
Post by Opus the Poet on Jun 21^st, 2009, 4:27pm

The plastic ones were Pyramid brand, those were the ones that I crushed a bearing and broke a race. The alloy bodied ones I bought so long ago for a different bike and never installed that I have no idea what brand they are. I ride platforms so I push on the power stroke a lot and nothing on the up stroke except enough pressure to keep my feet from coming off. I had to move my feet to the outside of the pedal to keep my heels from hitting the cranks, that might be a major part of it, because the ball of the foot is almost directly over the outer bearing, the one that failed on the cheap plastic pedals.

Title: Re: Broken Pedals, again
Post by evblazer on Jun 21^st, 2009, 8:42pm

Paul even with twice that load I've never broken a pedal. I snapped a crank arm once but that was unloaded.
Opus,
If you think it could be from putting your feet so far out power_bent mentioned pedal extenders which would push the pedal more to the outside so you could be centered. I have a set which I tried which didn't work for me but I'd be glad to send em on over to yah. They'd push the pedal out a little potentially evening the force between the sides. Or perhaps a pair of power grips?

Title: Re: Broken Pedals, again
Post by FlyingLaZBoy on Jun 22^nd, 2009, 8:23am

I was thinking about the Power Grips, as well....

Title: Re: Broken Pedals, again
Post by goatstick on Jun 22^nd, 2009, 12:52pm

Opus the Poet wrote:

I keep breaking pedals, as in putting power into them end they stop working and parts fall off breaking.

Am I dealing with bad pedals? I don't think my power output is the cause for this, or I would be doing a much higher average, because my cruise speed has been in the 15 MPH range. Yes, I'm slow [smiley=deadhorsebeat.gif] but I get there eventually. [smiley=rolleyes.gif] If I am breaking pedals because of the power I am generating I can't wait to see the times I run on the drag race trike I'm building [smiley=dbanana.gif]

I'd suspect bad/cheap pedals. I've blown up two SRAM Dual Drive hubs and one Ultegra hub on my trike using inexpensive pedals with Power Grips and I only wore out the bearings on one pedal (wore out two sets of Power Grips though). I use Shimano A530 pedals on the trike and the LWB bikes now and Shimano A520s on the Corsa. I even burned up the bearings in the stock FSA BB on the Corsa a couple of months ago and the A520s are still in great shape, though I've worn out two pairs of bike shoes in the past year. Hoping my new Sidis do better.

Title: Re: Broken Pedals, again
Post by Opus the Poet on Jun 22^nd, 2009, 2:58pm

Latest repair was putting the cages back on after I stripped out the threads holding the screws in the body. [smiley=shrug.gif] I went to put power into the pedals and almost broke my ankle when the cage collapsed to the outside, and this was on my bad leg, the one with the weak ankle. It would be funny if I was watching it on some cable network reality program, not so much in real life...

Title: Re: Broken Pedals, again
Post by Opus the Poet on Jun 30^th, 2009, 5:44pm

Cages back on, but I noticed something on the ride. I was trying to get across an intersection near sunset so that I could see the shadow cast by the bike on the pavement, and I was pulling the front wheel off the ground under power. Granted this was on Gigi rather than on my Stratus, but still, that's a lot of short term power. So we have the foot way out over the end of the pedals, we have a huge amount of power going into the pedals, and we have cheap pedals. We have the perfect storm for destroying pedals. [smiley=jawdrop.gif]