Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  

Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Thread Tools Search this Thread
Old 07-01-11, 08:18 PM   #1
Junior Member
Thread Starter
Join Date: Feb 2011
Location: Central Massachusetts
Bikes: 2003 GT i-drive 1.0. And looking for some classic pieces.
Posts: 24
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
unbolting bolt on crank arms.

I'm looking to unbolt the crank arms on my GT Idrive, but the bike shop loctited everything together. I'm just wondering if these bolts are right hand or left hand thread, or are the the same as the peddles right on right, left on left? Thanks.
noxyce is offline   Reply With Quote
Old 07-01-11, 08:26 PM   #2
Senior Member
oldbobcat's Avatar
Join Date: Jul 2005
Location: Boulder County, CO
Bikes: '79 Gios, '80 Masi, '06 Felt, early '60s Frejus
Posts: 2,964
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Both crank arm bolts are standard (lefty-loosey) threaded. After you remove the bolts you will need a crank arm extractor to remove the crank arms. See the Park Tool web site for instructions on removing and re-installing crank arms.
oldbobcat is offline   Reply With Quote
Old 07-01-11, 08:30 PM   #3
Jeff Wills
Insane Bicycle Mechanic
Jeff Wills's Avatar
Join Date: Mar 2008
Location: other Vancouver
Posts: 8,397
Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Quoted: 213 Post(s)
The bolts that hold on crankarms are right-hand thread. If they're on tight, count your blessings. Too-loose crank bolts will allow the crankarms to work loose, which ruins them.

FWIW: if you're going to take them off, you will probably also need a crankarm remover, like this: . There's a couple variations, so it would be nice to know what kind of cranks are on your bike. Also, when you put them back on, you'll want to torque them down properly- they should get 25 to 35 foot-pounds of torque. (See .) You can't do that very well with a little socket or hex (Allen) wrench.
Jeff Wills

Comcast nuked my web page. It will return soon..
Jeff Wills is offline   Reply With Quote
Old 07-02-11, 09:28 PM   #4
Senior Member
MudPie's Avatar
Join Date: May 2004
Location: Southern California
Posts: 1,874
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Using a threadlocking compound is unnecessary on a bicycle. If the fastener is torqued properly, it will be fine without any thread locker. In my experience, the crank arm bolts need about 30 ft-lb of installation torque (imagine a 30 lb weight hanging off a 1 foot wrench). And you'll need more than that to remove it. It's quite a bit of force, and I usually use automotive type wrenches to remove. You won't be able to remove with a multi-tool.

When you reinstall the bolt, grease the threads, to avoid sticking/corrosion in the future. And use of torque wrench is highly encouraged especially if you have square taper bottom bracket to crank arm interface. As Jeff pointed out, loose crankbolts is often a prelude to buying a new crank arms.

Also, you might want to wear gloves, so your skin doesn't meet the mean teeth of the chain ring when the bolt finally gives.
MudPie is offline   Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

All times are GMT -6. The time now is 11:13 PM.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to and affiliated sites.
  • Ask a Question
    get answers from real people!
Click to start entering your question.