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

Reply
 
Thread Tools Search this Thread
Old 09-11-05, 08:54 PM   #1
Ganesha
Senior Member
Thread Starter
 
Join Date: May 2004
Location: Tucson
Bikes:
Posts: 161
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Is this crank toast?

Or more specifically, are the threads on this crank usable?

I was riding along toady and all of a sudden my pedal bends and get stuck at about 10-20 degrees above its normal position.

Anyway, I get home and undo the pedal with a pedal wrench. With effort I can still thread the pedal into the crank and it seems to seat, but I'm skeptical if they will stay together under load.

The threads on the pedal look fine.

Ganesha is offline   Reply With Quote
Old 09-11-05, 09:03 PM   #2
AndrewP
Senior Member
 
Join Date: Sep 2001
Location: Montreal
Bikes: Peugeot Hybrid, Minelli Hybrid
Posts: 6,521
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I dont think they will take a load. Go to a well equiped bike shop and ask about helicoil inserts. If they have the tools to do this it would be a trustworthy solution.
AndrewP is offline   Reply With Quote
Old 09-12-05, 01:51 AM   #3
gmason
Senior Member (Retired)
 
gmason's Avatar
 
Join Date: Sep 2001
Location: Great North Woods
Bikes: Vittorio, Centaur triple; Casati Laser Piu, Chorus Triple.
Posts: 2,671
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
It looks as though the pedal was only half inserted (or less) when it failed. True?
gmason is offline   Reply With Quote
Old 09-12-05, 03:58 AM   #4
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Bikes: Rans Rockst (Retro rocket) Rans Enduro Sport (Retro racket) Catrike 559, Merin Bear Valley (beater bike).
Posts: 26,739
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 141 Post(s)
Well, you can always replace the crank later if you need to. If it was my bike I think that I'd try the cheapest solution first. I'd run a pedal tap through from the back side to clean up whatever thread is left and see how it goes.
Retro Grouch is offline   Reply With Quote
Old 09-12-05, 03:14 PM   #5
Ganesha
Senior Member
Thread Starter
 
Join Date: May 2004
Location: Tucson
Bikes:
Posts: 161
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Well I first felt the pedal start to go, to pedal was 1/2 inserted, couldn't have been like that for more then a week, since I have pictures from last week that clearly show the pedal was fully inserted.

Anyway started with the cheap (free) solution and had the the LBS and had the LBS run a tap though it.

I'll see how it holds together for the next few rides.
Ganesha is offline   Reply With Quote
Old 09-13-05, 01:10 PM   #6
crgowo
Senior Member
 
crgowo's Avatar
 
Join Date: Feb 2004
Bikes:
Posts: 388
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Retro Grouch
Well, you can always replace the crank later if you need to. If it was my bike I think that I'd try the cheapest solution first. I'd run a pedal tap through from the back side to clean up whatever thread is left and see how it goes.
Pretty much what I did when the exact same thing happened on a friends bike. But I instead of a tap I just used the pedal. Screwed it in on the back inside of the crank all the way in to clean out the outer threads then put the pedal in the correct side. Never had a problem since.
crgowo is offline   Reply With Quote
Old 09-13-05, 10:03 PM   #7
poopncow
MADE IN HONG KONG
 
Join Date: Aug 2005
Location: Washington DC
Bikes: some but not enough
Posts: 1,763
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Some old machinists used to tell me that 7 turns (of thread) is all you ever need. Not sure how true.

College story: A hand me down bike had the pedal striped completely off and brazed back on ! (b4 being handed down to me) . 2 years of service and then the pedal came off on the climb at the very northern tip of Central park. It took a while to limp back to the lower east side
poopncow is offline   Reply With Quote
Reply


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 01:48 AM.