You are riding along one day and you are practicing some stuff in you favorite parking lot.  Today the trick to learn is the fire hydrant.  You have been getting close to hitting the trick and you have even pulled a lucky one or two of them today.  Then, out of nowhere you find that the frame is spinning at you pretty quickly, but you know you are safe because it's going to hit the ground before it hits your shins.  KA-PWING!  What the heck was that!  Sounds like a guitar string breaking...  hmmm, no sign of any guitar players around though.  Probably just a spoke - only, you don't see any broken spokes.  Alright, the frame?  Nope, bike frame looks fine.  You roll the bike forward a bit, sit down then realize that you must have snapped the frame because your entire bike is wobbling from side to side, right at... your back wheel.  You check again and once again come up empty.  The frame isn't broken, but it still wobbles side to side.  You reach your hand out and grip the rear tire firmly and wobble it.  Sure enough, it's going about half an inch, maybe a full inch side to side.  Looking closer, you see that it does NOT look like the frame is flexing at all.  Congratulations, you just broke an axle.

Now, replacing an axle really isn't that hard under most circumstances - but we are going over a worst case scenario.  This means, that the hub is a freecoaster instead of a freewheel or a front hub.  A freecoaster is a type of hub, typically used by flatlanders, it allows the cranks not to move while the rear wheel is rolling backwards.  To accomplish this, a few additional pieces have to be added inside the rear hub of the bike and these pieces can cause some problems.

Something else to keep in mind is that if you own a freecoaster it is a good idea to take it apart, clean it, and regrease it about once every 6 to 12 months.  This is an explanation on how to do that as well - you just skip the part where you pull a new axle out and throw away your old one.  I mean, why throw out a perfectly good axle right?

Here we go...

TOOLS REQUIRED Not much is needed for this job, you will want a ratchet with a deep socket extension and the right size deep socket to remove your axle nut, cone wrenches (see below), grease, and WD-40.  Also a small or medium adjustable wrench and don't forget some rag towels to clean stuff up! Oh yeah, and a replacement axle. Rag Towels Courtesy Motel 6

First and foremost if you think you have broken your bicycle axle do not ride your bike anywhere!  This is a sure way to completely destroy your hub and the parts that go inside of it.  A hundred bucks of replacement parts and a week or two of no riding while you wait for replacement parts isn't worth you having to walk home.  Now, let's start things off by discussing what you are going to notice about a broken axle.  With the bike upside down, grip the tire firmly, and try to move it from side to side.  If your axle is broken you will find that it probably goes about an inch or two from side to side.  If it's seriously broken, you will probably hear some parts inside shaking around.

Examine your rear wheel.  This is a view of the right side of the hub with the bike upside down.  As you can see there are bearings that are not in the hub right now.  Believe it or not, those bearings should be inside the hub, not outside and visible for all to see.  If you see your bearings outside your hub, you can bet that the axle is broken.

A close-up view here of the bearings outside of the hub.  As you can see they are very dirty and if the axle hadn't broken, it was beyond time for this particular hub to be taken apart and rebuilt anyway.  The broken axle is just a very final reason to do so.

On the left side of the bike (with it upside down) we find the rear sprocket with the chain still on it.  The cone and lock nuts are visible.  Also visible is the rear dropout and the peg.  At the bottom of the image you will see the chain tensioner which will be the first thing we will loosen up so we can take the rear wheel off the bike.

The chain tensioner is still doing its job and is keeping the chain nice and tight.  Using an adjustable wrench, or a wrench of the correct size, loosen the bolt that holds the end cap of your chain tensioner in place.  You don't have to completely remove the bolt, you just have to move it enough so you can take your chain off the bike.

Grab your ratchet and extension with a deep socket the correct size for your axle nut.  All you need to do is rotate the ratchet counter-clockwise to get the axle nut off the bike.  You will want to remove the axle nut completely from both sides off the bike and the pegs should just be able to slide off the bike.  Take your axle nuts and the pegs and set them to the side until you are ready to put them back on.

With the pegs removed from the rear wheel, you are now ready to take the rear wheel off right?  Well, there are still a couple of things holding the rear wheel on.  One of which is not obvious...

The brake pads on the back of the bike probably will not let your tire pass between them without letting the air out of your tire.  While this is a definite option, there are many sets of brakes out there that allow you to quickly release them and will allow the wheel to slide off.

These particular brakes are Odyssey Evolver brakes and they have cable anchors in place that can be popped off when you need to do so.

One moment later, the brake cable is off the rear brake calipers and you will now be able to get the rear wheel off without any obstruction.

Once the brake cable has been quick-released from the rear calipers, just set it down.  If you need to, do the same to the other side of your calipers.  If your brake calipers are not quick-release style, then go ahead and let the air out of your tire.  It's easier to fill a tube back up with air than it is to completely readjust your rear brakes.

Time to start getting your hands dirty.  Remove your chain from your front sprocket.  This may take a little bit of work depending on how loose your chain is.  Make sure to pull it to the outside of the sprocket.

Set the chain down on the edge of your crank arm so that it doesn't get in the way.

Now remove the chain from the rear sprocket and let the chain dangle out of the way.  The chain will not need to be touched until it needs to be reinstalled until the rear wheel is back on the bike.  But, at this point you should find that the rear wheel just slides right off the bike.  Hopefully, you are above a nice clean surface when you pull the rear wheel off the bike, because, with a broken axle, everything may go everywhere...

Sure enough, upon pulling the rear wheel off of the frame the two sides of the axle fell off the hub and parts tried to go everywhere.  But, since the wheel was close to the ground and we were ready, we were able to make sure that everything fell exactly where we wanted it to go.

Gather all of the pieces of your hub together.  Make sure that everything that came out of the hub is there.  Check inside your hub to see if anything else is in there and put it with your pile of greasy parts.  Don't worry about keeping your hands clean as you are about to play with all the greasy parts.

Pull out one of your rag towels and begin wiping everything down.  Wipe down every part that came out of the hub and then wipe the hub down as well.  This may take a couple of rag towels, or a lot of paper towels to get the job done.  As you can see in this photo, a lot of grease is on the parts so the first wipe down will get 99% of the grease and dirt off your parts.  Once again, don't forget to clean your hub.

After the first wipe down, you may find that you have a couple of parts that are still locked onto the axle.  For some reason these pieces won't come off... Why?  Well, the reason is that on both sides of the axle there is a lock nut holding pieces together.  Here the locknut (far right) is pressed against a spacer which is up against the stationary driver.  This is when you will need a couple of tools to free things up.

A cone wrench of the correct size is put onto the stationary driver, which has a flat part to allow a cone wrench to fit onto it.  Then, using your adjustable wrench, put this onto the lock nut.  Twist the wrenches in opposite directions.  The wrench on the right goes down and the cone wrench on the left goes up.  If the nuts are particularly tight, this may take a little muscle.  Remove the final pieces from the broken axle and wipe them off with a rag towel.

With the first wipe down complete, it is time to really clean things up.  With any piece of bike equipment that will be supporting your weight coming out of tricks and putting hundreds of pounds of force on the axle and stuff inside your hub it is very important that no metal filings or dirt be inside the hub at all.  The secret to this is using some WD-40 which is a top notch degreaser.

Spray the WD-40 onto every part that came out of your hub and carefully clean them all thoroughly with a clean rag towel.  Pull as much grease, dirt, and grime off of every piece as you can.  It may be several months before you do this again, so go ahead and take the time to do this part correctly.  This is the most time consuming part of the task if you do it correctly.  Do not leave any WD-40 on the parts when you are done as it will break down any new grease you put in the hub.

PARTS CHECK TIME!

This is a Suntour freecoaster but many of the parts will be similar to what you will find on a Nankai or other freecoaster.  Even the Haro Turbine or Odyssey freecoasters will be similar on the inside.

Lock Nuts:  Two of these, one on either side of the hub on the far outside of the hub when it is built up.  These nuts do exactly what their name implies.  That is, they tighten against another nut to lock it in place.  Because a wheel floats on bearings, you don't want the parts they float on to be to tight or the wheel won't spin and it will destroy the hub and bearings.  These hold everything exactly in place.

Spacer:  A spacer is put between the stationary driver and its locknut.  This is to keep the wheel centered on the bike.  If you look at your rear wheel when it is built up and on the bike, one side will have a sprocket on it and on the other side you will find this spacer.

Cone Nut:  This little sucker is what the bearings float on so that the wheel spins.  As you can see in this photo there is a curved grove at the top of the nut.  This is the grove the small set of bearings sits on.  This piece is threaded on the inside and on the bottom of this photo you can see that the nut is in fact flat on the sides to allow a cone wrench to fit onto it for adjustment.

Small Bearing:  The small bearing of a freecoaster fits inside the driver and is held in place with the cone nut.  This is one of the three bearings that go inside a freecoaster.  This particular bearing has small balls that are inside a metal piece called a cage.  The cage keeps the balls from going all over the place but should not intrude into the operation of the hub itself.

Large Bearings:  Two of these go into your hub.  One on either side of the hub.  As with the small bearing, the balls are caged.  Technically, these are ball bearings and a cage as separate pieces.  But, put it all together and it become one caged bearing.

Stationary Driver:  This is one of those weird pieces that you will only find in a freecoaster.  It is threaded on the inside and has flats on the far left side which allows a cone wrench to fit onto it and adjust it.  Bearings fit onto this piece on the left side where it indents slightly.  The stationary driver is long because other parts inside the hub ride on it and use the fact that it doesn't move to make the hub more reliable.

Unbrake:  This is a product made by Standard Industries specifically for the Japanese Suntour freecoaster.  It has several cuts into it and basically looks like a modified washer.  It slides onto the stationary driver (above, on the right side) and keeps the clutch from moving to far out of position.  On your hub, this piece may truly just be a washer or two.  Multiple washers which create the unbrake can be used in greater or smaller quantities to adjust slack in your particular hub.

Clutch:  Just like in a car, this is what engages and disengages from your hub to make the wheel spin.  The clutch slides left to right inside the hub. But, it isn't truly attached to anything.  It kind of floats inside the hub.  On the left, it butts up against the unbrake.  On the inside of the left a spring fits and on the inside on the right it is threaded for the driver to go into.  The right outside of the clutch locks into the hub when you pedal which propels you forward. Stop pedaling, and the clutch disengages, back pedal and it hits the freecoaster and stays a few millimeters away from engaging the hub.

Friction Spring:  No question about it, this is the piece that manufactures screw up more than any other.  Either a simple C-shape like this one, or two small flat pieces of metal.  The spring fits into the clutch (above) and applies friction to the clutch so that when you pedal forward the clutch actually engages the hub the way it is supposed to.  A properly designed freecoaster allows for the friction spring to fit onto the stationary driver loosely, and not spin at all.  It may wear the spring down more quickly, but it makes the hub work much better.

Driver (& rear sprocket):  In the old days... like 1998, these were separate pieces.  Nowadays, you should be able to find a one piece sprocket/driver combination.  Suntour drivers and rear sprockets are always separate items.  You would find a lock ring that would be holding the rear sprocket onto the driver.  But, if you are smart, you take the pieces into school to the auto shop class and ask for them to do you a quick favor.

The favor is for them to weld the sprocket onto the driver.  Make sure they only weld on the outside of the driver as you definitely don't want them to screw up the inside edge.  Also, you want to make sure they do a clean enough job that when your chain slides over the rear sprocket it doesn't bunt up against any left over welding material.  You will need to pull out a grinder if the chain hits the rear sprocket.  Also visible is the track in which the small bearing fits into.

The other side of the rear driver is threaded.  While the sprocket is outside the hub, the threaded side is inside the hub; specifically, it threads into the clutch.  When you pedal forward, it threads into the clutch and pulls it against the hub, engaging it so you go forward.  Back pedal and it unscrews the clutch until the clutch hits the unbrake.  Then the clutch can't unscrew anymore.  You can still pedal backwards, but the clutch simply spins against the unbrake.  While threaded on the outside, the driver is not threaded on the inside, it floats on the axle.

Shell:  This is what many may just call the hub.  But, it's not, it is the shell of the hub.  The hub is the total package of all its parts.  Now, with a freecoaster there is a wide side and a narrow side.  The wide side allows all the pieces to fit into it and inside the hub you can see that it gets narrower.  It actually narrows at a very specific point and that point is where the clutch engages the hub and spins the wheel forward when you pedal.

Shell - Narrow Side:  This side of the hub is setup for one of the large bearings to fit right into.  The bearing sits inside what is called the bearing race and are trapped between the race and the driver.  The driver passes into the hub and threads into the clutch.

Shell - Wide Side:  Everything that goes into the hub fits in from this side, and one of the bearings will fit on the far outside on this side.  You will find that there is a slight bearing race that doesn't hold the bearings tight, but when it's all put together does a good enough job to keep things running smooth.

Now, you should check all the parts of your hub for wear and problems.  As is true with every part of your bike, the hub will eventually wear out and need replacement.  But, by checking carefully every part listed above, you may be able to extend the life of your hub by many months, if not many years.  The pieces should all be smooth and free from wear.  Check www.flatlandfuel.com and send them an e-Mail if you need to order some replacement parts for your hub.

In this case it was discovered that one of the bearing races was missing a couple of bearings.  One of the bearings was found and one was lost at some point prior to the hub being worked on.  Your local bike shop will be able to provide you with replacement ball bearings if you need them.  Simply pop them back into the bearing race and if necessary, slightly squeeze the bearing race with pliers to keep them in place.

With all the parts checked out and knowing that you are ready to build up your rear hub and put it back together so you can ride.  Pull out a new axle (if this is an axle replacement).  Make sure you have the correct axle and that it is a high quality axle.  For 3/8" axles about the only quality ones made are by Standard Industries or Kink.  Check www.flatlandfuel.com for your replacement axle.  Do not get a cheap, generic chromoly axle from your local bike shop as you will most likely break it about five times quicker than a high quality axle.  These axles cost about $15.00, but the cheap ones are $5.00 - so that saves you money in the long run.  In fact, the Standard Axle on the front of this bike is over ten years old!

Lay out all the pieces to your hub and double check that you have everything there.  The axle at the top, then left to right are the following parts:  Lock nut, spacer, large bearing, stationary driver, unbrake, friction spring, clutch, large bearing, driver, small bearing, cone nut, and lock nut.

We are going to dry fit everything together to show an example of how it all fits.  First and foremost, put the friction spring on the stationary driver.  Notice that the stationary driver is grooved for the friction spring to fit onto it in a specific direction.  Flip the spring over, and it won't fit onto the stationary driver as nicely.  If you try to install it backwards then you will destroy the friction spring and could cause severe damage to your hub.  There will be another view of this later.

Dry fit all the pieces together off of the axle.  The friction spring (above) goes into the clutch so that it slides onto the stationary driver as shown above.

Another view of all the pieces together and this time you can see the small bearing inside of the driver.

One last dry fit with everything on the axle except the lock nuts.  Most important here is that you want to center everything up so that there is the same amount of extra axle on both sides of the parts.  About an inch and a half here is what you see on both sides.  Now, you want to put the large bearing on the left and the left side lock nut onto the axle.  Remove all other pieces from the right side of the axle up to the unbrake.  Do not remove the stationary driver.  You may want to slightly tighten the lock nut against the stationary driver to make things easier to work on.

Pull out your tub of quality grease and we will begin to cover up all the parts we just spent so much time cleaning up.  A freecoaster should have a lot of grease put on every part that goes into it.  Do not apply a thin coat of grease, pile it on!  The grease protects the parts and makes everything run smooth and also will help protect the pieces inside the hub when dirt or metal filings get into the hub.

First grease up the stationary driver and the bearing that is on it.  When greasing the bearing, make sure that you get grease all over the bearing especially where it comes into contact with the stationary driver.  The bearing race should have it's flat metal surface on the left side and the open exposed bearing on the right side.

Slide the unbrake onto the stationary driver and make sure that it fits securely.  Apply grease to the entire package.

Before putting the clutch onto the stationary driver make sure the friction spring is inside the clutch and that it has been installed correctly, as shown in the photo.  Put some grease into the clutch and all over the friction spring.

Slide the clutch and friction spring combo onto the stationary driver and add some more grease.  Check everything out to make sure that it has been thoroughly coated with grease as you won't be adding more grease until the next time you build the hub.  Set the axle to the side, propping it up on something so that you don't mess the grease up or get dirt into everything for just a minute so you can...

Grease the inside of the shell.  As with everything else you want to make sure that you put a healthy coating on the entire hub.

Pick up the axle with all the pieces on it and insert everything into the hub on the wide side.  Everything should slide right in and then stop when the bearing is fully inserted into the hub.  The bearing may need to be jiggled around a bit to get it to fit inside nicely because it is a very exact fit.  When everything is done and the bearing is in, you should only see the outside edge of the bearing race.  Clean the grease off of everything that is outside the hub on this side with a rag towel.

We will move onto the other side of the hub and begin greasing things up.  There shouldn't be any grease on the axle, but in case you got some onto the axle, don't worry about it.  Just clean it off when the hub is all the way together.

Set the wheel down on its side so that you can get to work greasing up the rest of the parts that are left to go into the hub.

Pick up the driver and begin by putting some grease into the bearing race side.

Now you want to put some grease onto the threads of the driver and grease down to the bearing race.

Put the other large bearing onto the driver with the flat edge of the bearing down and pressed up against the driver.  Apply some grease to the bearing and make sure the threads of the driver are covered properly.

Slide the driver onto the hub and screw it into the clutch.  You should have no problem screwing it into the clutch, but if you find it just doesn't fit inside, then it is likely that you have the wrong clutch inside your hub.  No, it will fit without any problem.

Grab the grease and put it onto the small bearing and then put the bearing into the driver.  As before, you want the flat edge of the bearing cage to be towards the outside of the hub.

Finally, put some grease onto the curved part of the cone nut and screw it onto the axle until it is finger tightened against the hub.  Now, screw the lock nut onto the axle until it is pressed against the cone nut.  Now you should go ahead and grab your cone wrench and adjustable wrench and tighten the cone nut against the lock nut firmly.  You won't be adjusting this side again so make sure you tighten it up securely.

Take a quick look at the back of your bike to make sure that everything looks straight.  Now would be the time to grab some Windex or 409 or Simple Green and attack the back of your bike on a cleaning frenzy.  Okay, this has no impact at all on how well you ride so it's just to make your bike pretty.  So do it or don't do it... doesn't matter.

Slide the rear wheel into the dropouts and onto the frame.  Put the chain back onto the rear sprocket and onto the front sprocket.  Also, reattach your rear brakes using the quick release tabs if you had taken them off earlier.  This is all exactly opposite of what you did earlier to take it all apart.

Take a quick look at the back of your bike and make sure that the wheel looks straight and that the same amount of axle is sticking out of both sides of the hub.  The measurement does not have to be exact, but you want about half and inch or more sticking out of the side of the side of your bike.  If you only have a tiny bit of axle showing on the sides, then you didn't use a Kink or Standard axle most likely and you probably can't run pegs.  Start over and get a good axle this time!

Slide the chain tensioners onto your bike if you have them and go ahead and tighten them up.

The chain tensioner pulls the axle backward in the dropout and pulls the chain tight.  By its design, it does not allow your axle to slide forward which means that your chain can't pop off your front or rear sprocket unexpectedly.  Also, this will keep your rear wheel from shifting from side to side as easily as it might otherwise.  They cost less than $20.00 for a quality pair (two!) and will last you several years.  In fact, they may last you through several different bikes.  Good deal.

You can see that the space on this side of the hub is pretty tight to try to get a wrench and cone wrench into so you better have tightened everything up earlier.

You will want to put your pegs back on the bike, but a quick word first about checking your axle nuts and replacing them if they are stripped out or worn.  A good alternative would be axle nuts like the one pictured.  It doesn't require a deep socket adapter, instead, the socket extension just plugs right into it.  You should be able to pick up a pair of these special axle nuts for your rear axle from www.flatlandfuel.com - Make sure to tell them BMXTRIX sent you!

With your axle nuts ready to go, go ahead and put the rear pegs back on your bike.  Tighten up the left side so that it doesn't come loose, and then put the right side up.  You will probably have to adjust the cones on the left side of your bike so don't over tighten the right side peg at this time.

Grip the rear wheel firmly and try to move it side to side.  With pegs tightened you should find that the wheel does not move side to side at all.  If it does, loosen the left peg and tighten the stationary driver using a cone wrench, then tighten the lock nut against the cone wrench.  Go ahead and tighten the peg back up and repeat this process until the rear wheel does not jiggle from side to side.

Now give the wheel a good spin.  It should spin fast a long.  If it seems like it stops quickly then you want to do the opposite of what you were instructed to do immediately above.  That is, loosen the right peg, then loosen the stationary driver slightly and tighten the lock nut against the stationary driver then tighten the peg.  Make sure the wheel doesn't jiggle side to side again and then try spinning it again.

Your wheel should spin fast and smooth and should not stop to quickly.  Likewise, it should also not jiggle side to side.  The key is to have the stationary driver just tight enough so that the wheel doesn't jiggle.  If it needs to be a little tight for this to happen, then this is okay.  Make sure the lock nut is tight against the stationary driver (with the spacer in between) and then tighten the peg down firmly.

The rear wheel is all set to go and you should go out and do some riding.  Make sure to take your tools with you the first time you go ride though as it is very likely that as the grease settles into all the nooks and crannies of the freecoaster and any replacement parts get their initial workout the wheel will start to jiggle side to side.  Tighten it up immediately!  A loose hub is the number one reason why axles break in the first place.  You will want to periodically check your hub to make sure it is tight and adjust the stationary driver to keep things perfect.