Bicycle Mechanics - Is it easy to remove the left crank arm?

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




jair101
02-19-12, 03:13 AM
Hey guys. I am switching the pedals of my road bike, but the left one is hopelessly stuck. As per Sheldon Brown's instructions I want to try to heat it on a stove. Is it relatively easy to remove the arm and subsequently reattach? I.e. just remove the arm, without breaking the seal of the BB and so on.

Thanks


hueyhoolihan
02-19-12, 03:27 AM
most bikes made in the past 50 years have crank arms that can be removed easily if you have the right tool. here's a common one. pics of your crank would help.

http://www.unicycle.com/media/catalog/product/cache/1/image/5e06319eda06f020e43594a9c230972d/p/a/park_ccp-4_isis_crank_arm_removal_tool.jpg

it's advertised for 16.50.

viewpic
02-19-12, 05:06 AM
Pedal or crank arm


reptilezs
02-19-12, 05:42 AM
what crank?

RubberLegs
02-19-12, 05:44 AM
You ARE aware that the left hand pedal is opposite thread? Just checking, as I have to stop and think a bit WAY too often if threads are right or left handed...old bottom brackets drive me nuts!

Bianchigirll
02-19-12, 06:27 AM
You ARE aware that the left hand pedal is opposite thread? Just checking, as I have to stop and think a bit WAY too often if threads are right or left handed...old bottom brackets drive me nuts!


YEP I agree! turn the wrench towards the back to remove pedals and towards the front to install them. Do you have an actual pedal wrench? the extra leverage is very helpful

MudPie
02-19-12, 08:20 AM
In addition to the pedal wrench, put some thread penetrant like Liquid Wrench or PB Blaster to loosen the joint.

A typical pedal wrench: http://www.amazon.com/dp/B000OZBK32/ref=asc_df_B000OZBK321905512?smid=A2XX5CY7UG6Z5F&tag=hyprod-20&linkCode=asn&creative=395105&creativeASIN=B000OZBK32

I find it easier to remove pedals on the bike because you can use the opposite crank for leverage

Also, when trying to remove pedals on the bike, wear a pair of leather gloves to protect your hands from meeting the teeth of the chainring. Although this is more relevant to the right side, it's good overall practice in case something slips.

And when you reassemble the pedal, place grease on the threads and no need to tighten it with gorilla strength - snug it down and off you go.

jair101
02-19-12, 12:33 PM
I am aware of the reversed thread on the left crank, I tried all available wrenches, but it still stuck. I blame the LBS from which I bought the bike, apparently they didnt grease the pedals when they attached it. The right one was pretty tough too, but finally moved, the left one is like chuck norris. Here is the pic of the crank arm:

http://img9.imageshack.us/img9/3710/p1000013u.jpg (http://imageshack.us/photo/my-images/9/p1000013u.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

To me it looks like it can be detached easily with alien wrench, but I want to make sure I won't screw something up.

RubberLegs
02-19-12, 01:32 PM
That "Dust cap/crank nut combo does come off with an allen wrench, THEN you need the afore mentioned Crank-puller, that threads into the crank and then you screw the little lever to push the crank off of the spindle/axle.

hueyhoolihan
02-19-12, 01:35 PM
sometimes cranks and their attachment bolts that look like that are removable without the use of a crank puller. i used to have one like that. it's a combination of the bolt and that threaded dust cap that allows this self removable quality to happen on ones that it happens on!.

it's been a while since i had one. i'm sure some helpful soul with chime in here shortly with a full expose on self removing crank bolts/dust caps. be patient. and stay thirsty. :)

RubberLegs
02-19-12, 02:18 PM
I have heard of the self extracting bolts, I have not dealt with them...anyone? Does this one look normal or like a self extractor? I am thinking normal, but I have been known to be wrong more than right! ;-)

reptilezs
02-19-12, 02:28 PM
that is not a self extracting bolt. use the appropriate puller

Spld cyclist
02-19-12, 04:23 PM
Did you try extending the wrench handle with a length of pipe or something similar? No stuck pedal will fail to yield to a couple extra feet of leverage.

jair101
02-19-12, 04:49 PM
I tried everything that is under my disposal. I tried both pipe wrench and the normal 15mm wrench. I tried with hammers, tried with extendor(albeit small and not very efficient one), tried liquid thread losener - it doesnt move. On top of that the nut started wearing off, so i wanted to try the heating method before I destroy it completely. I tried to heat it up with cigarette lighter as I dont have buthane torch, but it didnt work either.

I dont feel like wasting money on special tool just for this, I guess I will bring it to the LBS to deal with it, but they are a little bit away.

reptilezs
02-19-12, 05:32 PM
that pedal doesn't really look siezed on, pretty cherry. i have had worse rust and crap. i enjoy a good challenge getting corroded stuff apart without breaking it. that is nothing, put your lunch in to it. place left arm forward, put a quality 15mm wrench on and step on it

IthaDan
02-19-12, 06:26 PM
Depends if you think it's easy to remove the right crank arm.

And that 8mm allen crank bolt isn't left threaded- just the normal righty-tighty lefty-loosey. You're going to feel pretty foolish pretty soon if that's what holding you up.

EDIT: I'm talking about this bolt-

http://i.imgur.com/gka72.jpg

sk0tt
02-20-12, 06:34 PM
jair101, you could try and slowly pour boiling water over the crank at the pedal hole. This has worked for me (but i placed the end of the crank in boiling water) with a rusted pedal which I broke a spanner on. Do this on a path or driveway and not your grass :)

gyozadude
02-20-12, 06:59 PM
It's hard to believe you'd get better leverage taking the crank arm off the bike. Yes, the boiling might work. But I'm hard pressed to think of anything more effective than an 18 inch long pedal wrench, putting the left crank forward in the 9 o'clock position, then have someone holding the bike on firm ground and then you kneeling with two gloved hands on that wrench . (Chain must be on and someone hits the brakes). But I've yet to see a pedal that stuck. If you get it free, can you show a pic?

Bill Kapaun
02-20-12, 07:09 PM
Have you actually tried some penetrating oil on the pedal threads?

ivan_yulaev
02-20-12, 10:17 PM
Crank bolts are normal threaded on both sides.

Get a 1/2 drive ratchet and some allen bits. Flip bike upside down, put down some towels to avoid scratching the bike and the floor. Have an assistant gently press the head of the wrench into the bolt (to avoid stripping it, it's not that easy to strip it but it SUCKS if you do) while you do a press-up on the pedal and the ratchet. I've never failed to budge it this way.

Edit: having the assistant hold the rear brake while you pull together the crank arm and ratchet head with one hand (once again, to avoid stripping the bolt) while wailing on the wrench with the other hand is a good idea. Shift into the highest gear (big front - small rear) and drape a rag over the chainring area - there is a chain over it so you shouldn't hurt yourself too bad if you slip but it sucks either way.

onespeedbiker
02-21-12, 12:39 AM
I don't think the issue is removing the crank arm, what the OP wants to do is remove a stuck pedal and they are debating whether the OP should remove the crank arm to do so.

leob1
02-21-12, 11:24 AM
I've ran into this same situation a few times. The last resort to getting the pedal off the crank is to remove the crank from the bike, and putting it in a bench vise. The use a deadblow hammer to hit the wrench. You'll need a crank puller tool, it's ahndy to have so it's not a waste of money to buy one, you'll use it again. Make sure you're turning the correct direction.

Myosmith
02-22-12, 06:19 AM
I've had luck removing seriously stuck pedals at the bike co-op by using the long pedal wrench, applying lots of pressure, then having someone else give the wrench a hard tap or three with a hammer. The shock seems to loosen things that steady pressure will not.

larwyn
02-22-12, 02:48 PM
Since the pedal is already off the other side, why not slide a cheater pipe over that crank arm while using a long pedal wrench on the remaining pedal. The cheater bar should prevent the crank from rotating as well as a vise and with less risk of damage to either crank arm. It has worked for me in the past.

Bill Kapaun
02-22-12, 03:00 PM
Have you actually tried some penetrating oil on the pedal threads?

Well?

BikeWise1
02-22-12, 04:11 PM
No need to pull the crank. You need to think about leverage. In 30 years, I have yet to fail to remove a pedal by carefully balancing forces. Penetrant will help, as will warming the aluminum near the pedal carefully with a torch.

bobotech
02-22-12, 04:31 PM
A LONG extension on the wrench being used to loosen the pedal will work. Like others are saying, its about leverage. Even if all you have is a standard box end wrench, you can still put a 3 foot or so long pipe around it and make it into a 3 foot breaker bar. Just need a piece of pipe 2 or 3 feet long (or longer) that will fit over the wrench. Have someone on the other side firmly hold the crank in place (maybe with the wheels off and the bottom bracket resting on a towel on the ground) and the put the wrench on and then slip the pipe over it and loosen in the proper direction.

Did you use penetrating oil too?