How to tell - bent crank arm or pedal?

[JRobert]

I wrecked several months ago (broken collar bone, 3 broken ribs), and have been riding for the last week or so, and have noticed some irregularities in my bike. Mainly, the chanrings are bent somewhat and the chain rubs on the right downstroke, but I think I can fix that. The main problem is that my right knee is getting sore after a ride (12 - 18 miles Mtb Bike), and I think that it has to do with either the crank arm or the pedal. The right pedal does not spin as freely as the left, although I does not appear to be out of line. Same for the right crank arm, it does not look like it is out of line.

How do I go about isolating the problem? Chances are it might have to go to the LBS, but I'd like to avoid that if possible. They are fine folks, but very busy, and I want to ride, not wait.

Thanks, JR

 

[clue]

JR , The first thing you will need to do is get a pedal wrench or a 15 mm open end wrench if a pedal wrench is not available and remove the right pedal. Pay attention to any side to side movement in the wrench as this can be a sign of a bent pedal spindle. Once the pedal is off the bike hold it in one hand and spin the spindle from side to side with the other. If you notice any binding you most likely need to replace the pedal and see if your knee feels better.

Now if the pedal appears to be fine use a adjustable wrench and a pair of needle nose pliers to straiten your chain rings. Once your chainring are fairley strait take a 8mm hex wrench and ensure your crank arm bolts are tight. (If you have a older crankset you will need a 14 or 15 mm socket to acomplish this. Next stand aft of the crankset with your head next to the chain and rotate the cranks backwards. If there is any side to side movement while rotating the cranks you probably bent you crank arm.

Now lets pretend your pedals are good and your cranks are good. It has been my experiance that knee pain can be caused by either having your saddle to far forward or aft. Also I have had many people tell me that there knee pain dissapeard after the bought a different style of pedal, usually with more float than the one the experianced knee pain with.

JR I hope you find some of this info helpful. If it doesnt remedy the problem your local bike will.
John Cloutier
Bicycle mechanic
Ryders Hillsboro,OR

 

[JRobert]

Thank you very much, John. This is my project for the day!

JR , The first thing you will need to do is get a pedal wrench or a 15 mm open end wrench if a pedal wrench is not available and remove the right pedal. Pay attention to any side to side movement in the wrench as this can be a sign of a bent pedal spindle. Once the pedal is off the bike hold it in one hand and spin the spindle from side to side with the other. If you notice any binding you most likely need to replace the pedal and see if your knee feels better.

Now if the pedal appears to be fine use a adjustable wrench and a pair of needle nose pliers to straiten your chain rings. Once your chainring are fairley strait take a 8mm hex wrench and ensure your crank arm bolts are tight. (If you have a older crankset you will need a 14 or 15 mm socket to acomplish this. Next stand aft of the crankset with your head next to the chain and rotate the cranks backwards. If there is any side to side movement while rotating the cranks you probably bent you crank arm.

Now lets pretend your pedals are good and your cranks are good. It has been my experiance that knee pain can be caused by either having your saddle to far forward or aft. Also I have had many people tell me that there knee pain dissapeard after the bought a different style of pedal, usually with more float than the one the experianced knee pain with.

JR I hope you find some of this info helpful. If it doesnt remedy the problem your local bike will.
John Cloutier
Bicycle mechanic
Ryders Hillsboro,OR