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 05-28-08, 09:34 PM   #1
Matterbator
.
Thread Starter
 
Join Date: Apr 2008
Bikes:
Posts: 137
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Fixie project: Is filing drive-side dropouts necessary? Please help!

Hey all. I just recently purchased a 1987 (I think) Schwinn World Sport frame on ebay in hopes of turning it into a little fixie side project. This will be my first attempt at building a bike. I recently found the exact (or so it looks) frame that was made into a fixed gear on Velospace.org. I was happy to see it can, and has, been done, however I read up that old school road bikes with drive-side dropouts like the one on this bike can be quite problematic for making a fixed gear.

http://i295.photobucket.com/albums/m...mp/4-22001.jpg
That's the bike I bought.

http://i295.photobucket.com/albums/m...p/IMG_4090.gif
This is the fixed gear I found online. (He obviously made it work w/ the dropouts) I do not know if he cut them or just left it as is.

http://i295.photobucket.com/albums/m...mp/4-22014.jpg
Here is an example of the drive-side dropout.

http://i295.photobucket.com/albums/m.../rightd8fn.jpg
And here is another example from some other bike just to highlight what it looks like.

Now, I've heard some can manage without filing/cutting the dropout back (depending on gear ratio), although some have to shave it back and just kind of test it as they go. If I were to do this method, what tool would you recommend using to file it back? Any tips would be wonderful since I'm not familiar with either bicycle building or.. filling/cutting metal in general. Should I try to really convert this sucker? I'd like to get my hands a bit dirty and learn as much as possible since that's my main goal, aside from creating a sweet personalized ride. Thanks in advance!
Matterbator is offline   Reply With Quote
Old 05-28-08, 09:49 PM   #2
MrCjolsen
Senior Member
 
MrCjolsen's Avatar
 
Join Date: Nov 2004
Location: Davis CA
Bikes: Surly Cross-Check, '85 Giant road bike (unrecogizable fixed-gear conversion
Posts: 3,957
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
My first fixed gear conversion was on an old Giant that had dropouts just like those.

Yes, I filed them.

The best way is to get a round file that is about the diameter of the dropout, hang the bike by a font wheel and just start filing. It will take some time, but progress will come faster than you might think.

The closer you get them to where the non-drive side is, the better.

However, if are able to get good chain tension with the whole axle nut on the dropout, and you don't want to change the gearing at all, then it's fine the way it is.

But if the chain is loose when the axle hits the rear dropout, or if any part of the nut is off the dropout, then you should file it a little so that you can get good tension.

Basically, the goal is good chain tension with a axle that is securely bolted to the dropout. What you don't want is your axle sliding off because the nut wasn't on the dropout enough or the chain derailing because it didn't have good tension.

It's also nice to be able to run different sized rings or cogs. But that's not essential.
MrCjolsen is offline   Reply With Quote
Old 05-28-08, 09:53 PM   #3
Thumpic 
Senior Member
 
Thumpic's Avatar
 
Join Date: Dec 2007
Location: The Sunny South
Bikes:
Posts: 1,858
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Why would it be a problem? Just be sure the axle is well seated in the drive side and the wheel is centered and parallel to the center line.......make your chain the right length....and go for it........
Thumpic is offline   Reply With Quote
Old 05-28-08, 10:38 PM   #4
Matterbator
.
Thread Starter
 
Join Date: Apr 2008
Bikes:
Posts: 137
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Awesome, thanks guys =]. Guess I'll hit up a local hardware store and get to filling. Also, do you have any recommendations on gear ratios? I live in San Francisco which is kinda hilly. I'm leaning towards 48-16 but not sure yet. Thanks!
Matterbator is offline   Reply With Quote
Old 05-28-08, 10:43 PM   #5
JiveTurkey
Low car diet
 
JiveTurkey's Avatar
 
Join Date: Aug 2007
Location: Corvallis, OR, USA
Bikes: 2006 Windsor Dover w/105, 2007 GT Avalanche w/XT, 1995 Trek 820 setup for touring, 201? Yeah single-speed folder, 199? Huffy tandem.
Posts: 2,407
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Don't skid much with that chainring/cog combo--you'll wind up with one bare spot (two if you're ambidextrous).
JiveTurkey is offline   Reply With Quote
Old 05-28-08, 11:07 PM   #6
Matterbator
.
Thread Starter
 
Join Date: Apr 2008
Bikes:
Posts: 137
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by JiveTurkey View Post
Don't skid much with that chainring/cog combo--you'll wind up with one bare spot (two if you're ambidextrous).
Ah yeah. What would you recommend? I know sheldon brown's site has a little calculator up so you can pick one that would allow for 3~ or so skid patches. Maybe I'll rethink it.
Matterbator is offline   Reply With Quote
Old 05-29-08, 06:46 AM   #7
jgedwa
surly old man
 
jgedwa's Avatar
 
Join Date: Sep 2006
Location: Carlisle, PA
Bikes: IRO Mark V, Karate Monkey half fat, Trek 620 IGH, Cannondale 26/24 MTB, Amp Research B3, and more.
Posts: 3,347
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Grinding out that filler metal in there is not hard and can be done if needed.

But, are you sure it is needed. Especially if you have the option of using a half-link, you should be able to get the chain length close enough so that the small amount of latitude you have in the drop currently should work.

You really only need 1/2" of latitude (and a half-link) in order to do what you want. More is better, since it means no need for a half-link, and/or the use of several different cogs, and/or less precision in cutting the chain.

If it were me, I would try first with the drops as they are, and then grind it if necessary.

jim
__________________
Cross Check Nexus7, IRO Mark V, Trek 620 Nexus7, Karate Monkey half fat, IRO Model 19 fixed, Amp Research B3, Surly 1x1 half fat fixed, and more...
--------------------------
SB forever
jgedwa is offline   Reply With Quote
Old 05-29-08, 06:55 AM   #8
Thumpic 
Senior Member
 
Thumpic's Avatar
 
Join Date: Dec 2007
Location: The Sunny South
Bikes:
Posts: 1,858
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Quote:
Originally Posted by jgedwa View Post
Grinding out that filler metal in there is not hard and can be done if needed.

But, are you sure it is needed. Especially if you have the option of using a half-link, you should be able to get the chain length close enough so that the small amount of latitude you have in the drop currently should work.

You really only need 1/2" of latitude (and a half-link) in order to do what you want. More is better, since it means no need for a half-link, and/or the use of several different cogs, and/or less precision in cutting the chain.

If it were me, I would try first with the drops as they are, and then grind it if necessary.

jim
+1........like I said......... Grinding the drop out should be a last resort; you may want to put it back original later........or someone may offer you top dollar for an original Schwinn frame; who knows...
Thumpic is offline   Reply With Quote
Old 05-29-08, 07:06 AM   #9
04jtb
Senior Member
 
04jtb's Avatar
 
Join Date: Mar 2007
Location: West Dorset, UK
Bikes: 1983 Dawes Galaxy, 2006 Raleigh Airlite, 1982 Sun Solo (fixed)
Posts: 908
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Matterbator View Post
Ah yeah. What would you recommend? I know sheldon brown's site has a little calculator up so you can pick one that would allow for 3~ or so skid patches. Maybe I'll rethink it.
something by 17
__________________
Quote:
Originally Posted by cc700 View Post
i jam my thumbs up and back into the tubes. this way i can point my fingers straight out in front to split the wind and attain an even more aero profile, and the usual fixed gear - zen - connectedness feeling through the drivetrain is multiplied ten fold because my thumbs become one with the tubing.
A group for all Dawes Galaxy owners to give and recieve information about them
http://flickr.com/groups/dawes_galaxy/
04jtb is offline   Reply With Quote
Old 05-29-08, 08:41 AM   #10
madman451
tinker
 
madman451's Avatar
 
Join Date: Jul 2007
Location: Minneapolis, Minnesota, USA
Bikes: Schwinn World, MOAB, Varsity; Trek 820, Miyata Five-Twelve rebuild
Posts: 64
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I have a Schwinn world sport fixie like this. I modified the dropouts. If you feel you have the finesse, an angle grinder will make 3 minutes of work of your dropout instead of 45 filing. 46/16 is tall, and I would especially think so for San Francisco. I run 46/19 in Minneapolis, which also has the advantage of 874 skid spots!

Good Riding.
madman451 is offline   Reply With Quote
Old 05-29-08, 08:47 AM   #11
dobber
Perineal Pressurized
 
dobber's Avatar
 
Join Date: Oct 2003
Location: In Ebritated
Bikes:
Posts: 6,557
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Matterbator View Post
Ah yeah. What would you recommend? I know sheldon brown's site has a little calculator up so you can pick one that would allow for 3~ or so skid patches. Maybe I'll rethink it.

Easiest thing to do is not skid. Mount a brake.
__________________
This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.
dobber is offline   Reply With Quote
Old 05-29-08, 09:04 AM   #12
jgedwa
surly old man
 
jgedwa's Avatar
 
Join Date: Sep 2006
Location: Carlisle, PA
Bikes: IRO Mark V, Karate Monkey half fat, Trek 620 IGH, Cannondale 26/24 MTB, Amp Research B3, and more.
Posts: 3,347
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
46x16 will make for pretty difficult skidding. Once you get the hang of it (mainly the art of unweighting the rear wheel), any ratio can be skidded. But it will seem impossible unless you are pretty adept at it already.

jim
__________________
Cross Check Nexus7, IRO Mark V, Trek 620 Nexus7, Karate Monkey half fat, IRO Model 19 fixed, Amp Research B3, Surly 1x1 half fat fixed, and more...
--------------------------
SB forever
jgedwa is offline   Reply With Quote
Old 05-29-08, 12:50 PM   #13
Joshua A.C. New
Senior Member
 
Joshua A.C. New's Avatar
 
Join Date: Aug 2007
Location: Northampton, MA
Bikes: Iron Monkey: a junkyard steel 26" slick-tired city bike. Grey Fox: A Trek 7x00 frame, painted, with everything built, from spokes up. Jet Jaguar: A 92 Cannondale R900 frame, powder coated matte black with red and aluminum highlights.
Posts: 956
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Just change that ratio by 1 in either direction to prevent wear holes.

Also, SF with no brakes? Yikes.
Joshua A.C. New 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 04:40 PM.