heavy cyclist pedal/crank arm size

[spencersoper]

Hi folks. I'm hoping someone can help me with this since I'm striking out searching online. I weigh about 260 (give or take) and I've commuted to work on a bike on and off over the past 10 years. My weight's been between 220 and 260 over that period, the lower end when I ride. So here's my problem. I purchased a Power King cruiser about a month ago and have been riding to work every day after a LONG hiatus. Feels great to get back on a bike. But I was pulling a hill in high gear yesterday and the pedal snapped off on me. This is the second time I've snapped a bike pedal. I got the old power king because I was worried about riding my old bike, a cheap Sears Crestwood, because I snapped a pedal off of that and took a pretty bad fall when I was quite a bit lighter. I replaced that pedal and continued riding, but was nervous about getting back on that bike afte packing on some pounds. So here'smy question: what's a good pedal o crank arm size for big cyclist. I've seen only 1/2 inch or 9/16. Or is there a stronger material I should look for that mkes the size irrelevant. I might just buy a new bike, bt I'm even worrried about that. I can't seem to find any kind of guide for weight/pedal size or material. Appreciate any help here.
Spencer

 

[maydog]

Are you saying that you broke the pedal body or the spindle?

I have broken several plastic platform type pedal bodies in my time but the spindles have never been an issue. I avoid plastic platform pedals if I can.

The spindles should be really strong. For example, I had to replace a worn pedal on my commuter a month ago. Either I torqued the pedal the wrong way or it became fused with the crank and was impossible to torque on the bike. I removed the crank and the pedal body. Using both torque and impact wrenches the spindle was unaffected.

The spindle only snapped, at its thinnest and most distal section, when I applied mucho torque using two 4 foot breaker bars. These were cheap ($25) wellgo SPD pedals on a cheap crank arm. Spindles should be sufficiently strong for almost all scenarios unless you have some defective or really poor quality pedals. A quick check of wikipeda indicates that 9/16 is pretty much the only option on spindle diameter.

Crank length wont have huge effect on the force placed on the pedals. I think at a given power, longer crank arms will have a ever so slight advantage by requiring less force.