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 01-18-14, 03:29 PM   #1
veganpower
Senior Member
Thread Starter
 
Join Date: Jan 2014
Bikes:
Posts: 53
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Chainring bolts

So I'm replacing my chainrings on my Shimano Ultegra FC-6500 crankset and realized that I might need new chainring bolts since mine are a bit old, although they probably work fine but it is nice too have a new set. What size should I buy and how do you measure the size?
veganpower is offline   Reply With Quote
Old 01-18-14, 03:31 PM   #2
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 19,614
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 431 Post(s)
take 1 out, go to the Bike shop and ask if they have 5 just like that?
fietsbob is offline   Reply With Quote
Old 01-18-14, 03:56 PM   #3
hueyhoolihan
Senior Member
 
Join Date: Dec 2010
Location: Above ground, Walnut Creek, Ca
Bikes: 7⃥ 9 road bikes
Posts: 6,401
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
here's what i know about chainring bolts.

come in aluminum or steel. there are five of them. pretty standard (one of the few on bikes, it seems) design.

length is usually determined by crank type. most LBS's will want to know how many chainrings are on your crank. single/track (1), traditional road (2), or MTB (3). i doubt if they know offhand the length of any of them, although they might make a good guess. cost (5), 10-20 bucks?
hueyhoolihan is offline   Reply With Quote
Old 01-18-14, 04:36 PM   #4
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
Posts: 29,660
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 217 Post(s)
Quote:
Originally Posted by veganpower View Post
So I'm replacing my chainrings on my Shimano Ultegra FC-6500 crankset and realized that I might need new chainring bolts since mine are a bit old, although they probably work fine but it is nice too have a new set. What size should I buy and how do you measure the size?
Unless there's been a change I missed, chainring bolts are highly standardized. You want a pair for double as opposed to track, but those are the most common. Your only choices are details like material, color, and Torx vs. 5mm hex key.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline   Reply With Quote
Old 01-18-14, 05:20 PM   #5
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Posts: 28,847
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 66 Post(s)
I have a couple of FC-6500 cranks on two bikes with thousands and thousand of miles on each and there isn't the slightest thing strange about the chainring bolts I can see. They are steel, standard size and length and take the usual 5 mm Allen key. What is your problem and what possible reason do you have for replacing them?
HillRider is offline   Reply With Quote
Old 01-18-14, 05:33 PM   #6
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
Posts: 29,660
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 217 Post(s)
Quote:
Originally Posted by HillRider View Post
and what possible reason do you have for replacing them?
Same as why a dog licks his balls----- because he can.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline   Reply With Quote
Old 01-19-14, 03:18 AM   #7
veganpower
Senior Member
Thread Starter
 
Join Date: Jan 2014
Bikes:
Posts: 53
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by HillRider View Post
I have a couple of FC-6500 cranks on two bikes with thousands and thousand of miles on each and there isn't the slightest thing strange about the chainring bolts I can see. They are steel, standard size and length and take the usual 5 mm Allen key. What is your problem and what possible reason do you have for replacing them?
Well, on a few of them I could see a bit of rust in the threads, although a little grease will probably do the trick. But I'm replacing them just because I'm putting on new front chainrings 52/39 so I can race junior next season. I'm sure they will probably work for another 5 years but it feels best to replace them with some new ones. So there is pretty much only 1 size for double cranks? How do you measure the size? Do you just measure the length of the screw or do you measure the distance from the big ring to the small ring including the spider?
veganpower is offline   Reply With Quote
Old 01-19-14, 09:10 AM   #8
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Posts: 28,847
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 66 Post(s)
Quote:
Originally Posted by veganpower View Post
How do you measure the size? Do you just measure the length of the screw or do you measure the distance from the big ring to the small ring including the spider?
Chainring bolts for double cranks (or triple cranks with a separate bolt circle for the granny) are pretty much standard length and diameter. Any bike shop should be able to provide replacements.

There are shorter bolts made for single chainring cranks and longer ones for triple cranks where all three chainrings are on the same bolt circle but double cranks are pretty universal. If you are concerned, take one of your old bolts to the bike shop to be sure you get a match.

Also, there are aluminum bolts which are both weaker and more expensive and some of the newer bolts use a Torx driver (T30 on my new Shimano crank) instead of a 5 mm Allen wrench. Avoid the aluminum bolts and be sure to get the appropriate Torx wrench if that's what your new bolts require.
HillRider 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 05:32 PM.