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 12-16-07, 10:55 AM   #1
seans_potato_business
A potato in every bite...
Thread Starter
 
seans_potato_business's Avatar
 
Join Date: Oct 2006
Location: Edinburgh, Scotland
Bikes: Pashley Princess Sovereign <3
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Pin/cylinder in my sprocket prevents use of a chainguard

I bought a new chainwheel/crank for my bike which uses hub gears. I removed the smallest of the three sprockets (the middle one is needed to keep the largest tight). The largest sprocket has a sort of metal cylinder (about 4mm diameter and 15mm length) in it, perpendicular to the plain of the sprocket, and pointing towards the crank arm. The cylinder is close to the edge of the sprocket and would therefore prevent me from having a chainguard over the sprocket. What is this cylinder (some might call it a pin)? It wont budge and is made from a different piece of metal than the rest of the sprocket.
seans_potato_business is offline   Reply With Quote
Old 12-16-07, 11:22 AM   #2
Gomez308
Senior Member
 
Gomez308's Avatar
 
Join Date: Oct 2004
Location: GA
Bikes:
Posts: 365
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
It keeps the chain from dropping between the arm and the ring.
Gomez308 is offline   Reply With Quote
Old 12-16-07, 11:24 AM   #3
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: 26,396
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
It serves two purposes, at least for other people. If you overshift it keeps the chain from becoming jammed between the chainring and the crank arm. It also indicates the proper orientation of the chainring so that the shifting aids will line up with the middle ring.

If it was my bike I'd chuck a cutting wheel into my Dremel tool and grind it off.
Retro Grouch is offline   Reply With Quote
Old 12-17-07, 07:30 AM   #4
seans_potato_business
A potato in every bite...
Thread Starter
 
seans_potato_business's Avatar
 
Join Date: Oct 2006
Location: Edinburgh, Scotland
Bikes: Pashley Princess Sovereign <3
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Unfortunately I'm a student in a foreign country and my rotary tool is at home. Maybe I can smash it off with a rock... - I'll see if a friend can help me out, or maybe even my landlord.
seans_potato_business is offline   Reply With Quote
Old 12-17-07, 07:47 AM   #5
nitropowered
Senior Member
 
Join Date: Dec 2004
Location: Athens, Ohio
Bikes: Custom Custom Custom
Posts: 5,104
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You can usually take/break it off with pliers. Or you can modify the chain guard
nitropowered is offline   Reply With Quote
Old 12-22-07, 09:11 AM   #6
seans_potato_business
A potato in every bite...
Thread Starter
 
seans_potato_business's Avatar
 
Join Date: Oct 2006
Location: Edinburgh, Scotland
Bikes: Pashley Princess Sovereign <3
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
It came right out with pliers and a bit of wiggling. I was scared off bending the sprocket but it hardly takes any force at all. Thanks for the advice
seans_potato_business is offline   Reply With Quote
Old 12-22-07, 03:20 PM   #7
sivat
Geek Extraordinaire
 
sivat's Avatar
 
Join Date: Feb 2006
Location: Long Beach, CA
Bikes: Bianchi Advantage Fixed Conversion; Specialized Stumpjumper FS Hardtail
Posts: 1,769
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You can also get single-speed length chainring bolts so you can get rid of the unused chainring.
__________________
I'd rather have a bottle in front of me than a frontal lobotomy.

Sintesi Conversion Serotta Track
sivat 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 07:47 AM.