FREECOASTER & AXLE
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...
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.
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
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.
later, the brake cable is off the rear brake calipers and you
will now be able to get the rear wheel off without any
|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
||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
|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
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
||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
|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.
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.
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.
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.
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.
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
|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
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
|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
||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
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
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...
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
|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
|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.
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.
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.
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.
About six months from now you will want to repeat the entire
process above, except hopefully this time you won't have to actually buy
a new axle to replace the old one. This is a good time to also
mention that every rider should have at least one replacement front and
rear axle for their bike available at all times. Also, while the
above method is the best way to rebuild an axle, it may be necessary for
you to do a quick change in the field. You may not be able to
clean off the old grease or add much new grease. The most
important thing is trying to keep dirt out of the parts after you take
them off, so do your best job. But, if that is the case, you will
still want to do a complete pull apart and thorough cleaning and
regreasing of the hub when you get back home and have time to do it