|Tips on Fixed??||Snyder|
Feb 26, 2003 8:34 PM
I am looking to build a fixed. I like the idea of doing it on the cheap, as a project / learning experience. I am handy, but have little bicycle mechanics experience. First thing would be to find a frame. What do I need to look for, and look out for? I would like to find a steel frame with clean lines... Suggestions? Criticisms?? Horizontal vs. vertical vs. angled "drop-outs." Proper term?
Any input welcome.
|re: Tips on Fixed??||Dad Man Walking|
Feb 26, 2003 11:06 PM
|This will hardly be a definitive treatise but here are a few starters that echo a lot of people on this board's experience:
Look for a frame with horizontal dropouts. These allow front-to-back adjustments of the wheel to properly tension the chain. Horizontal dropouts are angled down slightly and the wheel exits from the front (is that what you meant by "angled drop outs?")
Track frames have, and purpose-built road frames can be had, with "track forks" for the rear wheels. These are horizontal and the wheel exits from the rear of the dropout. These are are important for the track (along with axle nuts instead of quick releases) to prevent a monster sprinter from pulling the wheel out of the frame. For a road fixed gear bike, either works fine, and most of us get by just fine with quick releases on the road.
If you are stuck with a vertical drop out frame, you can play around with the chainwheel/cog combinations to get a setup that may work for the gear inches you want, and there are some new hubs out that offer a small amount of adjustment (like a concentric BB on a tandem) to further fine-tune the chain tension. But you'll make things a lot easier by just getting an older frame with horizontal dropouts or something with track forks.
If you have been following this board, you will understand that chain tensioners work for single speed freewheels, but do not work for fixed gears. If this isn't already obvious, post a follow-up and we will explain.
Regarding frame material, I would suggest that like always, fit is more imporant than material. Weight is not much of a factor for me, since I don't do extended climbing with the fixed gear. Durability is a plus, since this is my "crappy day" road bike. "Clean lines?" Whatever floats your boat. My converted road frame still has braze-ons for down tube shifters, top-tube cable tunnels, seat tube derailleur hanger, bottom bracket cable guides, a rear derailleur hanger, and a seat stay bridge drilled for a rear brake. None of which bug me in the least, and nobody has ever commented on them. Mostly I just get "whoa...what happened to your other brake?" People don't even notice all of the other missing parts unless you point it out, which I usually don't.
Are you thinking of fixed only or flip/flop fixed and freewheel? A freewheel option would be nice for extended descents, or to get you home if you were to bonk. My own experience is that I don't go "up" enough on a fixed to warrant a special "down" mode, and a gel in the jersey pocket (and knowing when to consume it) is a better way to manage the bonk that buying special equipment. One other argument that I have heard new riders give is that they would want coasting as an option when navigating "city traffic." Whatever that means. Once you pick up the basic zen (no coasting means, like, no coasting...really...ever...no kidding) and internalize some new riding habits, you'll probably find that "control" and "safety" are non-issues, and won't influence the equipment you would choose to use.
One question you'll have to answer yourself is "front brake only, or front/rear." At the end of the day, for a road fixed gear, I think that there is no compelling argument for "one brake" that makes any sense...after all, how much safety is too much safety? You don't need to use it if you want to work on backpedaling, and as I noted earlier, most fixed gear bikes do not see extended climbing so weight considerations are not usually relevant either. Rationally, two brakes. What's on my bike? One. Why? Because that's what my buddies and the wrench setting up the bike said was "appropriate." Did I argue? No. Am I a pig-headed moron? Yes. Do I have small children whom I want to watch grow up? Yes. Am I going to put the rear brake back on? Probably not. Why? I don't friggin' know. It's a guy thing.
|re: Tips on Fixed??||Snyder|
Feb 27, 2003 5:44 AM
|Thanks for the very complete and well written response.
Questions on two more items: the bottom bracket, and the rear hub.
First, the BB; older bikes have separate bearings and newer bikes are all one sealed mechanism. If I get an older bike that needs new bearings and axle, will I be able to find these parts, if so, where? Second item, is there a method of "fixing" a standard rear hub, or is it necessary to buy a track wheel?
I will probably go with only one brake, having two brakes is probably more sensible but this is not necessarily about sensible. I want it to be totally fixed gear as hills are not a problem. I live in Florida, and when I want to ride hills I drive about 60 miles to the closest rolling hills.
Feb 27, 2003 7:51 AM
|repl on comments||bigrider|
Feb 27, 2003 8:14 AM
|The first issue is the old bottom bracket. You can simply remove the old bottom bracket and replace with a new sealed one. Bottom brackets are cheap and if you want to go cheap on the cranks you buy the right bottom bracket to fit the cranks ( square or spindled). Your bottom bracket will be english threaded or italian based on the bike. To line up the cranks with the cog in the back you may want to measure and buy a certain width bottom bracket.
If you buy a steel frame bike you need to know if it is setup for 700cc wheels or 27 inch wheels. This will make a difference when putting on brakes if you try to use the 700cc on the 27inch frame, you will need longer arms to adjust the brake pads down.
You can convert a rear wheel to fixed and I have done so for three rear wheels. This makes sense if you have an old rear wheel laying around.There are two options. First, if you have the old style wheel that has the freebody that screws off as one piece, you remove and screw on a cog and lockring. Second, if you have a standard 8 or 9 speed cassette wheel you can tear it apart, weld the freebody, reinstall, use cassette spacers and one cassette cog and you have a fixed gear. If you want single speed eliminate the welding part and just load up the freebody with spacers and one cog. You can line up the cog in the back very easily this way instead of worrying about chainline issues with the chainrings and bottom brackets.
Track wheels are certain widths and so are bike frames. Measure frame and buy right width or adjust the width of the frame( this is easy with steel). If you need details I can show you a simple way.
|re: Tips on Fixed??||victorthewombat|
Feb 28, 2003 3:35 PM
|The only thing I would add is chainline on a fixed should be abount 44-48mm with a 126mm rear spacing. Line that puppy (fixed sprocket) with the front inner chain wheel and you should be good to go!!!!. Also, 1/8" chains are "phooey" and that's putting it lightly, don't scrimp here get a good derailleur chain and use 3/32" chainwheel and cog, without ramps and you should be set. I use a SRAM PC-89 nice price, good chain.|
Feb 27, 2003 3:54 PM
|I make no claims on being an expert in any field, but found Sheldon Brown's page on brakes helpful in the front only vs.front and rear issue. With some practice, I feel comfortable with only a front brake, and minimal back pressure. The elimination of the rear brake is one less part to maintain. Two if you count the brake lever.|
|Rear brake (It doesn't hurt, it doesn't help)||Frank Tuesday|
Feb 28, 2003 1:55 PM
|The funny thing is that both statements are entirely true. You'll get no more efficient braking by having both than just the front. The only time a rear brake will do you any good is if your front brake stops working for whatever reason and you break your chain while riding steeply downhill and high speed. But even then, just unclip and shove your foot against the tyre using the seatstays as a brace. You'll stop almost as quickly and look a lot cooler in the process, which is why we fixie in the first place, right?
It all comes down to which side of the fence you fall on. The "It doesn't hurt" person errs on the side of caution, the "It doesn't help" person errs on the side of danger. The "I don't need a front brake" person errs on the side of the emergency room.