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 01-17-08, 01:28 PM   #1
jmichaeldesign
Senior Member
Thread Starter
 
Join Date: Sep 2007
Location: Colorado Springs, CO
Bikes:
Posts: 430
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Standard Thread for Rack/Fender Eyelets

Is there a standard thread for rack and fender eyelets. I don't want to buy a bunch of bolts I don't need/go to the hardware store 10 times.

It's an old schwinn mtn bike if that helps
jmichaeldesign is offline   Reply With Quote
Old 01-17-08, 02:25 PM   #2
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: 28,917
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 94 Post(s)
All of the bikes I've worked on use M5x.8 bolts to fasten racks and fenders to the dropout and fork eyelets.
HillRider is offline   Reply With Quote
Old 01-17-08, 03:44 PM   #3
wroomwroomoops
Sir Fallalot
 
wroomwroomoops's Avatar
 
Join Date: Jul 2006
Location: Helsinki, Finland
Bikes:
Posts: 5,275
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by HillRider View Post
All of the bikes I've worked on use M5x.8 bolts to fasten racks and fenders to the dropout and fork eyelets.
Another no-nonsense reply by HillRider. Seriously, you should be awarded a "Bike Mechanics subforum poster of the decade" - your posts are consistently great.
wroomwroomoops is offline   Reply With Quote
Old 01-17-08, 04:29 PM   #4
Grand Bois
Senior Member
 
Grand Bois's Avatar
 
Join Date: Mar 2005
Location: Pinole, CA, USA
Bikes:
Posts: 16,689
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 89 Post(s)
I have an oddball Fuji that uses 6mm bolts, but it's the only one I've seen that does.
Grand Bois is offline   Reply With Quote
Old 01-17-08, 04:39 PM   #5
bfromcolo
Senior Member
 
bfromcolo's Avatar
 
Join Date: Feb 2007
Location: Monument, Colorado
Bikes:
Posts: 379
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
My Axis uses 6mm on the rear and 5mm on the front. But I think all my other bikes have used 5mm.
bfromcolo is offline   Reply With Quote
Old 01-17-08, 05:16 PM   #6
cyccommute 
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Bikes: Some silver ones, a black one, a red one, an orange one and a couple of titanium ones
Posts: 18,056
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 226 Post(s)
Quote:
Originally Posted by HillRider View Post
All of the bikes I've worked on use M5x.8 bolts to fasten racks and fenders to the dropout and fork eyelets.
A 10-32 will work also and a 4mm allen wrench will fit in those.
__________________
Stuart Black
New! Pokin' around the Poconos A cold ride around Lake Erie
New! Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
An Good Ol' Fashion Appalachian Butt Whoopin'.
cyccommute is offline   Reply With Quote
Old 01-17-08, 05:40 PM   #7
Bob Pringle
Senior Member
 
Join Date: Oct 2005
Location: Ormond Beach, FL
Bikes: 2005 Specialized Roubaix Elite
Posts: 228
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Careful with those 10-32 bolts! A #10 screw is just enough smaller in diameter than a 5mm screw that it'll strip the threads in the hole pretty easily. Instead of torquing the 10-32 screw in very tightly, I use a drop of blue loktite and just snug the screw in place.

Regards,
Bob P.
Bob Pringle is offline   Reply With Quote
Old 01-18-08, 01:03 AM   #8
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)
Why not just use a 5mm bolt? It's not like they are very hard to find. Any decent hardware store will have them, or get a couple of friends together and buy a box from mcmaster.com. Using a #10 in a 5mm hole is like using vise grips instead of a wrench. Sure it will work, but you're going to damage stuff.
__________________
I'd rather have a bottle in front of me than a frontal lobotomy.

Sintesi Conversion Serotta Track
sivat is offline   Reply With Quote
Old 01-18-08, 08:15 AM   #9
cyccommute 
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Bikes: Some silver ones, a black one, a red one, an orange one and a couple of titanium ones
Posts: 18,056
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 226 Post(s)
Quote:
Originally Posted by Bob Pringle View Post
Careful with those 10-32 bolts! A #10 screw is just enough smaller in diameter than a 5mm screw that it'll strip the threads in the hole pretty easily. Instead of torquing the 10-32 screw in very tightly, I use a drop of blue loktite and just snug the screw in place.

Regards,
Bob P.
They've never been a problem in the hundreds of bolts I've...um...obtained from work. I have yet to strip out a rack mount on any bike I've used them on.
__________________
Stuart Black
New! Pokin' around the Poconos A cold ride around Lake Erie
New! Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
An Good Ol' Fashion Appalachian Butt Whoopin'.
cyccommute is offline   Reply With Quote
Old 01-18-08, 08:21 AM   #10
cyccommute 
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Bikes: Some silver ones, a black one, a red one, an orange one and a couple of titanium ones
Posts: 18,056
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 226 Post(s)
Quote:
Originally Posted by sivat View Post
Why not just use a 5mm bolt? It's not like they are very hard to find. Any decent hardware store will have them, or get a couple of friends together and buy a box from mcmaster.com. Using a #10 in a 5mm hole is like using vise grips instead of a wrench. Sure it will work, but you're going to damage stuff.
I use the 10-32 because finding a 5mm bolt isn't...or at least wasn't... as easy as you think. My local hardware store which is a really good one, didn't start carrying metric bolts until just a few years ago. I'm not sure you could find one at the big box stores now. Back when I started riding, metric bolts were a very special order item. In other words, don't ask because you'll get one of 2 reactions, either outright laughter or such a blank stare that you'd think the clerk had just gone comatose! 10-32 bolts worked and...as I've said earlier...have never damaged any of my bikes.
__________________
Stuart Black
New! Pokin' around the Poconos A cold ride around Lake Erie
New! Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
An Good Ol' Fashion Appalachian Butt Whoopin'.
cyccommute is offline   Reply With Quote
Old 01-18-08, 08:42 AM   #11
Stacey
Non Tribuo Anus Rodentum and off to the next adventure (RIP)
 
Stacey's Avatar
 
Join Date: Dec 2002
Bikes:
Posts: 9,161
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Any japanese motorcycle shop will have stocked them for decades. All the shops I worked it had a Wurth jobber come around and keep our bins full.

One shop even had Stainless Steel .
__________________
Stacey is offline   Reply With Quote
Old 01-18-08, 09:55 AM   #12
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)
Quote:
Originally Posted by cyccommute View Post
My local hardware store which is a really good one, didn't start carrying metric bolts until just a few years ago. I'm not sure you could find one at the big box stores now.
ACE, Lowes, Home Depot and OSH all carry metric fasteners. I can understand why they may have been hard to find 20 years ago, but even GM has been using a handful of metric fasteners for 10 years (which I discovered changing the brake pads on a 97 pontiac).
__________________
I'd rather have a bottle in front of me than a frontal lobotomy.

Sintesi Conversion Serotta Track
sivat is offline   Reply With Quote
Old 01-18-08, 10:04 AM   #13
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: 28,917
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 94 Post(s)
Quote:
Originally Posted by sivat View Post
.....even GM has been using a handful of metric fasteners for 10 years (which I discovered changing the brake pads on a 97 pontiac).
Longer than that. I had a 1978 Pontiac Grand Am that had a mix of metric and SAE fasteners. Apparenly the more recently redesigned components were metric and the older ones SAE. The general rule was if the bolt had a blue painted head, it was metric.
HillRider is offline   Reply With Quote
Old 01-18-08, 10:26 AM   #14
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)
Quote:
Originally Posted by HillRider View Post
Longer than that. I had a 1978 Pontiac Grand Am that had a mix of metric and SAE fasteners. Apparenly the more recently redesigned components were metric and the older ones SAE. The general rule was if the bolt had a blue painted head, it was metric.
Interesting. I assumed the difference between metric and SAE parts was where they had been sourced. I guess the lesson here is that auto parts stores have always been a good place to find metric fasteners.
__________________
I'd rather have a bottle in front of me than a frontal lobotomy.

Sintesi Conversion Serotta Track
sivat is offline   Reply With Quote
Old 01-18-08, 02:07 PM   #15
cyccommute 
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Bikes: Some silver ones, a black one, a red one, an orange one and a couple of titanium ones
Posts: 18,056
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 226 Post(s)
Quote:
Originally Posted by sivat View Post
ACE, Lowes, Home Depot and OSH all carry metric fasteners. I can understand why they may have been hard to find 20 years ago, but even GM has been using a handful of metric fasteners for 10 years (which I discovered changing the brake pads on a 97 pontiac).
It wasn't 20 years ago that they were hard to find...try less then 10...in a general hardware store. Lowes carried more stuff earlier (back when they were Eagle and had a far better selection of just about everything) and I've seen them popping up more in other hardware stores.

However, after talking to the machinist (and fellow bike rider) here at work, he was very surprised at how close the thread pitch and the diameter of the bolt are. He said that for a short bolt, like a rack bolt, there wouldn't be any issue. The diameter is 5000th's smaller but, for certain applications, they often drill their holes that much larger prior to tapping them so as not to break taps. He wouldn't suggest it for a bolt that has to go into something an inch or more but for a short thread like a braze-on fitting, it won't hurt anything and will hold just fine.

Something else to consider, if you don't want to chase the threads or don't have the taps to do it, bikes are painted after the braze-ons go on. I have yet to see one that has had the threads chased after painting so the hole size is even smaller than the M5 should use. A smaller diameter bolt is easier to put in then the larger M5 would be.

Essentially, a 10-32 isn't going to hurt anything. It certainly isn't a 'visegrip vs a proper wrench'.
__________________
Stuart Black
New! Pokin' around the Poconos A cold ride around Lake Erie
New! Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
An Good Ol' Fashion Appalachian Butt Whoopin'.
cyccommute is offline   Reply With Quote
Old 01-18-08, 03:07 PM   #16
TurdFerguson2
Senior Member
 
Join Date: Mar 2007
Location: Guelph, Ontario
Bikes:
Posts: 146
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
The pitch is shockingly similar. 10-32 = 32 threads per inch. M5x0.8 = 0.8 mm / thread. 1/0.8 = 1.25 threads per mm. 1.25mm * 25.4mm/in = 31.75 threads per inch.

They both use a 60deg angle on the threads.

Pitch diameter of 10-32 is 0.1697". M5x0.8 is 4.480mm = 0.1763".
10-32 UNF-2A (external thread) Major diameter= 0.1891" max - 0.1831" min
M5x0.8 Major diameter female = 5mm = 0.1969"

That gives you about 0.010" overlap, where normaly on a M5 thread you'd have 0.017-0.018" overlap. So, approx. half.

Mind you, except maybe water bottles, the majority of fender and rack mountings are largely subject to radial as opposed to axial forces. So, in general, you should be alright, but in my opinion you'd might as well us a proper M5 bolt if you can.
TurdFerguson2 is offline   Reply With Quote
Old 01-18-08, 10:16 PM   #17
joejack951
Senior Member
 
joejack951's Avatar
 
Join Date: May 2004
Location: Wilmington, DE
Bikes: 1984 Trek 660, 2003 Specialized Hardrock, 2004 LOOK KG386i (RIP), 2005 Iron Horse Warrior Expert, 2009 Pedal Force CX1, 2014 Islabikes CNOC 14 (son's)
Posts: 10,189
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 189 Post(s)
On a lot of parts we manufacture where I work, we'll cast one hole size and use it for both M5 and #10 tapped finished products. Note that we do use the appropriate taps though. I have installed #10 screws in M5 holes before but I'm pretty sure it was by accident. You can definitely feel that something is wrong although on a bike frame with paint in the threads, you'd be hard pressed to notice.

FWIW, I've never had a problem finding metric hardware in the past 15 or so years that I've had a use for it. Napa stores are a terrific source for hardware when you don't have time for mailorder.

If you ever want to tell if a bolt is metric or standard, an easy way to tell is to check for marking on the bolt head. Steel metric bolts using a numerical system for their strength rating (common ratings are 5.8, 8.8, 10.9, and 12.9). Stainless steel metric bolts are generally marked by their material (genereally A2 or A4 for 18-8 or 316 stainless respectively). Steel standard bolts using a dashed marking system that I'm very unfamiliar with only because the relatively moderns cars (mid 80's and up) I've worked on (where most of my wrenching is done) all use metric hardware, save for my parents' Canadian-built 1988 Suburban which uses a mix. Stainless steel standard bolts (and sometimes washers) can be found marked with the actual stainless steel type (such as "316"). If it's unmarked, it could be either.
joejack951 is offline   Reply With Quote
Old 01-18-08, 10:22 PM   #18
wroomwroomoops
Sir Fallalot
 
wroomwroomoops's Avatar
 
Join Date: Jul 2006
Location: Helsinki, Finland
Bikes:
Posts: 5,275
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Important question: I need, for a vintage computer (Horizon), four imperial-threaded fasteners. No metric fastener will fit - and I don't want to destroy/strip the threads in the case. Where from can I order imperial fasteners (I live in Europe)? Remember, I need only 4 - that means, some shops won't even bother to answer me.
wroomwroomoops is offline   Reply With Quote
Old 01-19-08, 06:35 AM   #19
Stacey
Non Tribuo Anus Rodentum and off to the next adventure (RIP)
 
Stacey's Avatar
 
Join Date: Dec 2002
Bikes:
Posts: 9,161
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Look for a moto shop that does older (pre '70) British bike restorations. IIRC BSA, Triumph, Royal Enfield, etc. all used Imperial thread back in the day.
__________________
Stacey 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 07:25 AM.