Introduction
Most of the miles I have ever ridden are on a fixed gear bike on the road. The bike on my trainer also has a fixed gear. When I first got started in bike racing, I could time trial well, mash big gears, but I had absolutely zero leg speed.
I was told to make a fixed gear road bike. In a couple months I went from no leg speed to silky smooth at over 200 rpm on the road (my best ever rpm on the road is 218 rpm). An added benefit was that I found I could now "blip the throttle" and pop across a gap. My climbing improved because now I could sit and spin up a hill and easily manage changes in the grade of a hill, instead of standing and grinding up hills and getting bogged down with every little change in the grade of the hill. To borrow a term from the automotive world, I now produced good "torque" across a very wide "Power Band".
How to Make a Fixed gear Bike
You need a road bike with "road" dropouts. Remove the chain and the rear derailleur. Take the outer chain ring off and replace the chain ring bolts with track chain ring bolts. I use a 42 tooth front chain ring on my fixed gear bike. Notice that this means leaving the front derailleur on. This helps to keep the chain from jumping off.
You now need to make or buy a road rear wheel that has been converted to use a track cog. Because you cannot easily float over bumps, the rear wheel is going to take a beating. I use a heavier than normal clincher in the rear (and of course a clincher in the front). To make one, you need a rear wheel that uses a screw on freewheel (i.e. does not use a cassette). Remove the freewheel and screw on a cog. Here is the part that takes some time: you need to change the spacers in the axle, moving the hub to the bike's right, so that the cog is directly in line with the inside front chain ring (though "pretty" close is usually good enough). There is a magical sure fire way to do this: F**k with the position of the washers until the cog and inside front chainring line up properly. Obviously, as you move the hub to the right, you also need to be changing the wheel's dish to the left.
When you have finished making the wheel, put the wheel in the rear dropouts and put the chain on so that the wheel is in about the middle of the dropouts. The chain tension should be not firmly tight, but not loose enough that the chain can flop around and jump off. If the chain is too tight, you will hear a grinding noise. Proper chain tension is just "below" the point where you start hearing a grinding noise. Or put another way, when chain will not feel like it is "binding".
What can go wrong with building your fixed gear bike?
- If the drive side spokes are short to begin with, then you could run out of spoke before the dish is moved far enough to the left. If this happens, then replace the drive side spokes with longer spokes. Take the wheel to the store and show them what you are doing and they will be able to provide you with longer spokes.
- The cog and inside chain ring chain ring are not properly aligned. You have to get this right or the chain could jump off.
- If there is too much thread showing on the drive side spokes, then you will probably rip spokes out of the nipples. So use the correct spoke length.
- Conversely, if the spokes on the left side are too long, then they could stick through the rim strip and puncture the inner tube. So use the correct spoke length.
Equipment particulars
The type of chain depends on the type of cog used. You can get cogs for a road chain, or you can use track cogs and either a track chain or a three speed chain. A road front chain ring should work with either road or three speed chains. I prefer road chains and road pitch fixed gear cogs because some three speed chains are wider and therefore rock back an forth on the chain ring - causing excessive wear of the chain ring.
I use an inexpensive Specialized sealed bearing hub so I don't have to deal with maintenance, and 14 gauge straight spokes for the same reason.
I have been using the same Mavic GP4 rim and Specialized hub for many years. They still work just fine. I change the spokes every year.
How to get on and off a fixed gear bike
Get On: Mount the bike, hold the handle bars with both hands, put your right foot in the right pedal, slightly lift the back of the bike and pedal around until the right pedal is at 10 o'clock. Put the back of the bike back onto the ground. Sit on the seat and push with your right foot. Now you are moving slowly. Without stopping or losing your balance, put your left foot in the left pedal. TA DA!
Get Off: The same as you would with a regular road bike.
Special fixed gear riding problems
You cannot coast.
You cannot coast.
You cannot coast.
You cannot coast.
Did I tell you enough times: "You cannot coast"? I guarantee that you will forget I told you: "You cannot coast", and then you will coast once or twice and then you will learn this lesson. When you coast, the rear wheel will jerk up off the ground and it will scare you. The way to prevent going over the bars and crashing is to: (1) relax your legs, (2) pull on the handlebars like you would do arm curls in the weight room, and (3) resume pedaling when the rear wheel contacts the ground.
Track bikes use a lock ring to secure the cog to the hub. Using a road hub and cog means it is impossible to use a lock ring because there are no counter rotating threads on a road hub. The solution to securing the cog to the hub is (1) use almost no grease on the cog or hub, and (2) after putting the cog on the hub and properly mounting the rear wheel on the bike, STOMP on one of the pedals several times in a forward pedaling motion. This and just riding the bike will (almost) lock the cog to the hub. I say almost because since there is no lock ring, it is possible, but very improbable, that the cog could unscrew. If the cog does unscrew, it will just spin harmlessly on the axle. Use your two hand brakes on the bike and stop. Then put the cog back on the hub's threads and lock the cog to the hub as described earlier.
Gearing depends on terrain and the wind. I used to live about 20 miles north of Chicago in Highland Park, Illinois. The roads are small rolling hills that are lined with trees. The small rolling hills are absolutely perfect for riding fixed gear on the road. You have to focus on pedaling all the way around the circle going uphill and you get to really spin on the down hill, without getting out of control. The trees usually prevented the wind from being too much of a headwind or tailwind. When it was windy, I would bring another cog in a plastic baggie and change cogs when the wind changed. Now I live in Aurora, Colorado. The hills are alittle bigger, but there are no trees and there is a lot more wind. So I just freewheel during the windy time of the year: April, May and June.
Remember "You cannot coast"? It means some things regarding the driveability of the bike: (1) because you have to pedal through turns, you can't put the inside foot up and coast through the turn. This means you must learn exactly at what angle of lean, will the inside pedal nick the ground. When the pedal nicks the ground, the back wheel will lose some to all of it's cohesion with the pavement, possibly causing the back wheel to slide out alittle. (2) the bike will in general, drive a bit sluggishly meaning it will be more difficult to turn (3) when you master pedaling backwards, you will be able to slow down or stop a lot quicker than if you just used regular road brakes.
The ugly skeleton in fixed gear road riding's closet is getting something caught in between the chain and chain ring or cog. So obviously (1) do not wear loose clothing, (2) keep your shoe laces tied (and cut short and tucked in), (3) always wear shoes, and (4) keep fingers, important body parts, the family pet and of course grandmother away from the chain, chain ring and cog while they are moving.
Fun to learn
Can you RIDE BACKWARDS?
The skill: Balance while pedalling backwards. At first, this feels odd because you will think of balancing Left/Right even though: Rear is now front so left is now right. You should get it after a few tries. The other problem to overcome is visibility: going backwards; you can only look over your left shoulder, or your right shoulder = while going backwards, you never have a full field of vision = do what is necessary to ensure your safety and the safety of others.
Benefit: It is fun!
How about a NO HANDED TRACK STAND?