Left Pedal won't tighten

[John-XTC]

Hi there - I was cycling home today and the left pedal came loose, I am aware that the left pedal is tightened differently to the right one, but It won't tighten, and it no longer fits into the crank arm slot.

I have just ordered some new pedals, but just thought it could be the crank arm which is damaged? could the pedals have deteriorated the crank arm thread/slot (or whatever you call it)?

 

[bonj2]

could well be the crank arm, I had a mate who had the same problem and it was the crank arm. But could be either, best to test it with another pedal to be sure.
If it is the crank, then either cancel the pedals order or send them back unused for refund, and get new cranks.

 

[John-XTC]

Thinking about it, this may be my fault, as I had these pedals on for about 8 months, no problems, until recently i purchased another set, which I didn't like and returned, and when refitting the old pedals, I looked for the "L" & "R" but there was nothing, and I could have put the right pedal on the left side by mistake?

 

[yenrod]

Need a new left crank mate - quite cheap, most below a tenner !

 

[John-XTC]

If I buy a new left crank arm, are they quite easy to fit?

 

[Dave5N]

Mate, go to your local bike shop.

 

[John-XTC]

Mate, go to your local bike shop.

Yes Boss

I will do tomorrow, but while I am here, is it possible that I put the right handed pedal on the left crank, is that even possible?

 

[simonali]

Were you sweating profusely as you did it? I suspect you would've been there all day trying to screw a left handed pedal into a right handed thread!

 

[zimzum42]

Go to your local bike shop, buy the crank and the tool to fit it, then do the job yourself. You'll learn how to do it, and then never have to pay to get it done again.

Do this every time there is a problem and eventually you'll have a full toolset and will never need to pay a penny for labour when maintaining your bike.

Most of the time the tool for the job will cost the same as they charge to do the job for you anyway.....

 

[John-XTC]

Were you sweating profusely as you did it? I suspect you would've been there all day trying to screw a left handed pedal into a right handed thread!

Simon you funny man! but i actually switched over the pedals, and the pedal I had in the left crank fitted perfectly in the right crank, and vice versa so does that make any sense?..doesn't to me



zimzum42 - I just spoke with the LBS and they are pretty busy today, so just doing to buy the tool, crank arm, and I have a maintenance book - doesn't sound too daunting.

 

[zimzum42]

it really is pretty simple....

The only thing I get a shop to do is truing wheels and stuff with bearings, don't trust myself not to **** it up

 

[Odyssey]

Just undo the bolt inside and the crank arm will slide right off. Except it normally doesn't! And through personal experience I can say that you can bash it all day with a hammer and all kinds of prodding and levering implements, adding a good few scratches and dings to your bike and it's still not guaranteed to come off. So if you haven't already, save your self the bother and buy yourself a crank arm removal tool. Then it couldn't be easier.

As for the original problem, I've had it before too where the pedal kept coming loose, and the more it done it the more it ruined the threads until it just wouldn't stay in at all. And it will generally be the threads in your crank arm. To damage the threads in the pedal itself would be quite a feat - they're a lot tougher. When you fit it again, just make sure everything's screwed and tightened properly.

 

[briank]

Oooh - you great, strong brute you!

It would be difficult to screw the pedals into the wrong crank arms, but not impossible. The pedal spindle is steel and so the thread cut in it is much harder than the thread in the aluminium crank arm. (OK, conceivably, the pedal spindle is titanium - but you'd probably know that, as would your bank manager. And anyway Ti ia wlso much tougher than Al.) It's in theory possible that you could drive the pedal spindle into the wrong crank, the spindle thread just cutting through the soft aluminium as if there were no thread in the crank arm at all.

If that is what you've done, you've knackered the crank.
In fact you've knackered both of them, since if you've screwed the R/H pedal into the L/H crank, you've screwed the L/H pedal into the R/H crank.

But if your pedals are single-sided - like most Looks and Times - then putting them on the wrong cranks would end up with the pedals facing backwards! You'd notice!

So most likely your pedals are double-sided, you've just not tightened the left one up enough, and one new crank arm is all you need.

Hope so.

 

[bobg]

Oooh - you great, strong brute you!

It would be difficult to screw the pedals into the wrong crank arms, but not impossible. The pedal spindle is steel and so the thread cut in it is much harder than the thread in the aluminium crank arm. (OK, conceivably, the pedal spindle is titanium - but you'd probably know that, as would your bank manager. And anyway Ti ia wlso much tougher than Al.) It's in theory possible that you could drive the pedal spindle into the wrong crank, the spindle thread just cutting through the soft aluminium as if there were no thread in the crank arm at all.

If that is what you've done, you've knackered the crank.
In fact you've knackered both of them, since if you've screwed the R/H pedal into the L/H crank, you've screwed the L/H pedal into the R/H crank.

But if your pedals are single-sided - like most Looks and Times - then putting them on the wrong cranks would end up with the pedals facing backwards! You'd notice!

So most likely your pedals are double-sided, you've just not tightened the left one up enough, and one new crank arm is all you need.

Hope so.

What Briank said... its not impossible ... afraid I've done it too after a hard days fettling when temper and concentration is in short supply. I couldn't get a matching new crank so I took the stripped one to the local garage and they helicoiled it for the price of a pint. Its been there about 5 years now and is still fine. The following link will give you a clue http://coolercasesuk.co.uk/showthread.php?t=1211

 

[John-XTC]

Oooh - you great, strong brute you!

It would be difficult to screw the pedals into the wrong crank arms, but not impossible. The pedal spindle is steel and so the thread cut in it is much harder than the thread in the aluminium crank arm. (OK, conceivably, the pedal spindle is titanium - but you'd probably know that, as would your bank manager. And anyway Ti ia wlso much tougher than Al.) It's in theory possible that you could drive the pedal spindle into the wrong crank, the spindle thread just cutting through the soft aluminium as if there were no thread in the crank arm at all.

If that is what you've done, you've knackered the crank.
In fact you've knackered both of them, since if you've screwed the R/H pedal into the L/H crank, you've screwed the L/H pedal into the R/H crank.

But if your pedals are single-sided - like most Looks and Times - then putting them on the wrong cranks would end up with the pedals facing backwards! You'd notice!

So most likely your pedals are double-sided, you've just not tightened the left one up enough, and one new crank arm is all you need.

Hope so.

I did make a stupid mistake, as I have been riding around for the past 3 weeks, with the left pedal in the right crank, and the right pedal in the left crank!!........It was when I picked up some new pedals, but the guy sold me the wrong size, so when I got home to fit them along with upgrading the disc brakes, the pedals obviously wouldn't fit, which left me pissed off! and I guess I just picked up the old pedals and tightened them without really thinking!.....anyhow, the guy at my LBS reckons there isn't any damage done to the right crank thread (but there must be?)...the left pedal did screw on perfectly to the right crank when i fitted it, is there any sensible reason for that?...they aren't double sided, as they have "L" & "R".

I have got the pedals on correctly, a new left crank, and next week I am going to be cycling 20 miles each day.....I should replace the right crank just to be safe? or if its been checked, does that rule out any damage?