Crank Arm Pedal Thread Repair
08-11-06, 10:10 AM
#1
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Crank Arm Pedal Thread Repair
I have an old aluminum crank arm with 9/16 pedal thread, and the pedal is hard to thread in halfway, and will not go all the way without more force than is sensible. The arm threads look rough, and the pedal will thread into a good arm.
So I need to repair the threads.
1. Do I need a tap, or a "thread chaser?"
2. What is a thread chaser, anyway?
3. Are thread chasers just good for pushing out dirt, or do they affect the threads themselves?
Do I have to assemble the pedal to the arm with reduced torque after the repair?
Ken "needa get the bike going!"
So I need to repair the threads.
1. Do I need a tap, or a "thread chaser?"
2. What is a thread chaser, anyway?
3. Are thread chasers just good for pushing out dirt, or do they affect the threads themselves?
Do I have to assemble the pedal to the arm with reduced torque after the repair?
Ken "needa get the bike going!"
08-11-06, 04:15 PM
#4
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Or, if you have junk pedals lying around, make your own taps. Cut 3 slots legnthwise across the threads with a dremel tool, then put them in using kerosene, wd 40 as cutting oil. (Remember, you need 2, LH and RH threads)
If it is french threaded, you can still use non french pedals, the pedals just go in very snug.
If it is french threaded, you can still use non french pedals, the pedals just go in very snug.
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Il faut de l'audace, encore de l'audace, toujours de l'audace
1980 3Rensho-- 1975 Raleigh Sprite 3spd
1990s Raleigh M20 MTB--2007 Windsor Hour (track)
1988 Ducati 750 F1
Il faut de l'audace, encore de l'audace, toujours de l'audace
1980 3Rensho-- 1975 Raleigh Sprite 3spd
1990s Raleigh M20 MTB--2007 Windsor Hour (track)
1988 Ducati 750 F1
08-11-06, 04:26 PM
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if they are french wouldn't they get stuck half way through and have them sticking out all goofy like?
08-11-06, 04:38 PM
#6
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Originally Posted by Road Fan
I have an old aluminum crank arm with 9/16 pedal thread, and the pedal is hard to thread in halfway, and will not go all the way without more force than is sensible. The arm threads look rough, and the pedal will thread into a good arm.
So I need to repair the threads.
1. Do I need a tap, or a "thread chaser?"
2. What is a thread chaser, anyway?
3. Are thread chasers just good for pushing out dirt, or do they affect the threads themselves?
Do I have to assemble the pedal to the arm with reduced torque after the repair?
So I need to repair the threads.
1. Do I need a tap, or a "thread chaser?"
2. What is a thread chaser, anyway?
3. Are thread chasers just good for pushing out dirt, or do they affect the threads themselves?
Do I have to assemble the pedal to the arm with reduced torque after the repair?
Once you have repaired the threads, tighten the pedals normally (pretty snug.)
Sheldon "Day Is Done...Gone The Sun..." Brown
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08-11-06, 04:42 PM
#7
Senior Member
Originally Posted by ryanparrish
if they are french wouldn't they get stuck half way through and have them sticking out all goofy like?
__________________
Il faut de l'audace, encore de l'audace, toujours de l'audace
1980 3Rensho-- 1975 Raleigh Sprite 3spd
1990s Raleigh M20 MTB--2007 Windsor Hour (track)
1988 Ducati 750 F1
Il faut de l'audace, encore de l'audace, toujours de l'audace
1980 3Rensho-- 1975 Raleigh Sprite 3spd
1990s Raleigh M20 MTB--2007 Windsor Hour (track)
1988 Ducati 750 F1
