New Coker: Hunter frame, Stockton wheel

My new Coker arrived this morning. I’m still at
the office admiring it, as yet unassembled.

The frame was built by Rick Hunter, then shipped
to David Stockton (U-Turn) for assembly with his
Super Wheel. I shipped David my saddle with GB
handlebars. He took my measurements and put
together the whole package. I’ve attached a
picture he sent to tease me a few days before
it was shipped.

I’ll take it out for a moonlight ride (full moon!)
tonight on it’s maiden voyage, then provide some
reviews and feedback. I can hardly wait.

In the meantime, David included some useful
information in a detailed email after the Coker
was shipped. I found it interesting enough
that I thought I’d share his comments with this
forum. I’ve elided some irrelevant stuff.

David’s comments:

Seat: ----------------------------------------------
I rebuilt the seat, adding the stiffener plate and
replacing all the hardware with stainless steel that
has better specs than the original. On the front 3
and back 2 bolts the bolts have been retained with
nuts which should completely eliminate the spinning
problem. On the back 2 I actually opened up the hole
in the bumper to allow the nut to sit down in, then
added the washer. On the center 4 that attach to the
adapter this was not possible without compromising
the seat coupling, so they are only retained by the
traditional duct tape. There is a better solution;
I just haven’t found it yet.

Handle: [refers to GB handle] ---------------------
I had to move the cyclo mount over because it was
interfering with the brake lever. A local welder
did the work.

Cyclometer: ----------------------------------------
The cable is long enough for a little bit of seat
adjustment. To raise the seat significantly you may
have to slide the sensor and magnet up a bit. You
will see that I shimmed out the sensor to get close
enough to the magnet.

Seat post: -----------------------------------------
Should be cut properly for 150mm cranks and your specs,
so you may have to raise it a little for the 140s that
are installed. It is currently at the very bottom of
allowable travel and is resting on the cross-tube. It
is not possible to remove the top piece of the seat post
without loosening up the seatpost adapter due to the
saddle’s tight clearances. To loosen the adapter you
will have to remove the back bolt on the handle.

Frame: ---------------------------------------------
We had to do a lot of work to clean up the inside of the
seat tube. It was rough and there was some sort of hard
pin poking into the tube from the angled piece. I will
mention this to Rick. It should be fine now. The seat
post clamp is the one that came with the frame. If you
find that your seat is turning on uphills or mounts you
may want to go to a 2-bolt clamp like the Primo.

Brake: ---------------------------------------------
The brake seemed to come out very well. The bike
shop owner’s son, who has legs long enough to give
your uni a test run, preferred the feel to my
Magura setup. It seems quite smooth and modulatable.
It will change quite a bit as a) you get used to it,
and b) the cable stretches. For that reason, I
did not attempt to get the ideal setup, but just
got it into operating range. I will give you rules
to use for it though.

Setting up a brake for a uni is not the same as for
a bike. Here are some guidelines for you or for your

  1. It is ok if you can’t lock up the wheel when
    the brake is done. Unless you are doing trials,
    you will never need that much braking power. You
    will want smoothness and modulation much more than

  2. You should toe the brakes in much more than a
    normal brake. This improves modulation.

  3. One pad should hit the rim significantly before
    the other. This also improves modulation.

  4. You should move the brake pads out just enough
    to ensure that the pads do not hit the rim during hill
    climbs. The Super Wheel is absolutely the best going
    in this regard because it is far stiffer than any other
    big wheel arrangement. On your setup, one pad brushes
    the rim slightly in one spot. I left this because I
    knew that the cable would stretch.

Getting used to using a brake on a uni is different too:

  1. I recommend riding on the flats and just feathering
    it on to begin with. Despite all your attempted finesse,
    you will probably lose it the first couple of tries
    because of all the bicycle habits. My first brake
    application was on a country road hill and I few
    about 12 feet through the air.

  2. In order to get best use of the brake you need
    to start using at the top of the hill so that your
    balance point includes the brake drag. Trying to
    use it in the middle of the hill doesn’t work because
    you have to speed up the wheel to keep the brake from
    pitching you forward.

  3. A mental image that is helpful to me is to think
    of the seat post as a skid that I am digging into the
    road as I apply the brake. I have to get behind neutral
    balance and push the bottom of the seat post ahead of
    me into the road. This image helps get my weight back
    and down, so that the braking action works against
    my weight.

  4. Although your setup is not a drag brake, that
    has advantages on rough downhills because you can
    use the brake as an additional balance achiever
    instead of just a hill-flattener. Eventually you
    will use it all the time to save your legs, even
    on such mundane matters as coming to a stop.

  5. A uni brake doesn’t stop you, in contrast to
    a brake on a bicycle. A brake on a unicycle is like
    a power assist for your legs. It allows you to travel
    downhill more safely, and allows you to get out of
    the hill some of what you put into it.

Wheel: ---------------------------------------------
I think your wheel came out quite well. You can see
that I worked on the weld area as you requested.
Basically, that activity results in an area of the
rim that is of less width and less friction than the
rest of the rim. These characteristics, for a uni
brake, are far more desirable than the original,
which is a protrusion of higher friction where the
brake tends to dig in. An area of higher friction
is much harder to control and much more disruptive
of fore-aft balance. So, in general, there will be
some minor variation in braking force during a wheel

I used sleeve retainer on the bearings. If you remove
them chances are they will no longer be good, so I
suggest leaving them until you are ready to change
them. If you ride off-road or in sandy conditions
they will deteriorate much faster.

I have included two spare spokes. The installed
spokes use Wheelsmith Spoke Prep. The tension is
VERY high and I suggest that you either return the
wheel to me for truing (no charge, including return
shipping) or go to a really, really good bike shop.

I think you will notice a huge difference between the
feel of this wheel and that of your stock Coker.

Cranks: --------------------------------------------
The cranks are the Schwinn 140s. They do add a little
more Q to the leg position but you should not notice
this as a problem. The 125s, which are straight, are
in the box. I highly recommend the grease/torque
wrench approach to installing cranks, using 40 ft-lbs.
Please do not use a hammer at all. I have had customers
bend hub flanges in this way. If you need me to elaborate
on the installation procedure just ask.

Pedals: --------------------------------------------
The pedals will have plenty of grip. After a while
take a file and flatten off the pins and your traction
will improve once more. I recommend using blue Loctite
when you install the pedals.

Tire: ----------------------------------------------
I deflated the tire somewhat for better shipping
protection. You will, of course, want to repressurized
it before riding. If you need instructions about
changing the tire please let me know. The tire on the
Airfoil rim is actually easy to change if you know the
right procedure. I used talc between tire and tube. The
rim tape is Salsa 100% polyester.

Re: New Coker: Hunter frame, Stockton wheel

Rubic, it’s great to see another Hunter36 built up so nicely. I think you’ll
REALLY like that wheel. I’ve got about 800 miles on mine now and it is
working great - we did 30 hilly miles this morning before work! I’d like to
see some closer up photos showing the brake and underneath the seat if/when
you have time.

Have fun on it,

Sweet ride Jeff!
One word of caution. If you mount a computer where it supposed to be on the GB handle, make sure there’s enough clearance. I broke 2 of them on mine after UPD’s(before I switched to Wyganowski).

Wow, Dave sure took alot of time perfecting that for you!

Obviously this would make for a ridiculously expensive setup, but when I have the money, I already have Dave’s email addy!

That is beautiful!

What a sweet ride!!!

The Hunter muni owner in me is drooling, and wants to immediately sell my car or my kid’s stamp collection so I can trade in my standard Coker.

My baby needs a Big Brother…


Thats is a Beautiful coker. My standard coker had nothing on that.
Don’t think my rear end even deserves to sit on such a thing.

hmm - Coker?
I’m curious, how much of it is original Coker parts?

Tire is my guess.

And the tube.

Coker is a tire company. They make tires and tubes. What is original Coker parts on a stock Coker “The Big One”? I’d say the tire and tube. The rest came from a factory in Taiwan.

But is “The Big One” sold and marketed by Coker? If so, I’d argue that the frame is also “original Coker parts”, even if they’ve chosen to outsource part of their supply chain.

But of course, I’m just arguing back out of shame for missing the tube…

i need one more than ever now

Nearly tacoed me coker the other niche off a 1.5 drop that i hit veary badly like at a 45` angle it really was tacoed but sprung back to olny a 1/4 inch varience

how much did that come to

and what is the wait time


Have funn

Hey jugglero.

The wait time and cost are highly dependent on what you want your setup to be and what your leg length and preferred crank length are. If you, like your description, are doing off-road, including nighttime offroad, the setup is different than road riders (like Jeff Bauer, whose uni is above) and the other components are dependent on that. The basic wheel itself is $550 with high-quality bearings. This does not even touch the time I put into the wheel but that’s ok for now.

Right now the Airfoil rims are out of stock but I have some on reserve (and will add to that number I think).

PM me and we can work out all the details according to your needs, and perhaps get started so that when the rims become available we’ll be ready for them.

first ride

Our bike club had a moonlight ride on the Natchez Trace last
night. I had to trim a smigen off the seatpost length with
a pipe cutter before the ride. No problem. Better too long
than too short. It’s still a wee bit too high, which I
notice mostly when freemounting or climbing. The Hunter
frame has less travel than the stock Coker frame – the
amount it can be dropped is limited by the cross-tube.
Getting the proper seatpost length is important.

The ride itself went great. I rode about 9 miles out
on gently rolling roads, stopped for a few minutes,
then rode back. The total roundtrip was just over
2 hours (7.8 mph average).

Too many factors have changed to give it a proper
comparison with my stock Coker: pedals with pins,
shorter (140mm) crank arms, etc. But I did notice
with a truer wheel the amount of wobble is reduced,
particularly at higher speeds. I did not try to use
the brake – it was dark and I need to practice in a
more congenial environment.

The computer works great. I haven’t had time to do
a proper rollout, but based on the mileposts I passed,
my guesstimate calibration was reasonably close.

This morning I took it out for another quick 4 mile
jaunt just before work. I tried climbing a steep hill,
but UPD’d when I hit a bump. I still need to trim the
seatpost length so I can apply enough force properly on
the pedal stroke and also have enough maneuverability to
recover. The 140mm vs. 150mm crank arms are noticeable
on steeper up/down hills, but I’ll probably get used to
them when my setup is dialed in. On the less hilly
sections the shorter cranks rock.

I’m looking forward to more weekend riding.


niche=day not night had a brain fart or something i dont ride off road at night. thanks Uturn i will be Pming you soon

What a beast! :sunglasses:

Re: first ride

Originally posted by rubic
[B]Our bike club had a moonlight ride on the Natchez Trace last
night. I had to trim a smigen off the seatpost length with
a pipe cutter before the ride. No problem. Better too long
than too short. It’s still a wee bit too high, which I
notice mostly when freemounting or climbing. The Hunter
frame has less travel than the stock Coker frame – the
amount it can be dropped is limited by the cross-tube.
Getting the proper seatpost length is important.<

For my Hunter36 I had asked for a 5" seat tube. When Rick was setting his jig up for the (first) 36" frame/fork, he found that he could only go as long as 4". The jig wasn’t big enough.
As long as you are the main rider, that seat tube length is fine for whatever crank length you use. I have a spare seat with a very short post that I keep around for shorter riderswhen my set up is too big (I’m 6’-0" tall). It’s a pain to change out though due to the computer and brake etc.
I have stuck with the 150mm cranks. They seem to suit my riding habits well. On a 10 mile ride there are times when I’m spinning quite a bit and would like a shorter crank but I like the control at intersections and for the light off-road stuff I do with it.
Besides, I’ve got a very nice set of Kooka 150mm Razor cranks that just “will not be ingnored”.
I have stuck with the Magura brakes. I don’t use tham alot but I sure am glad I have them.
Rubic, your cycle looks great. The Hunter36 has been everything I had hoped for. Have fun!

  • Frank

Rick tells me (in an email that was eaten by something :angry: ) that he could get down to a 3" tube. I think he changes the angle of the slanted tube to do so. I may have to do this myself because my legs are happily short. I couldn’t ride Jeff’s, for example.

Jeff was a real pleasure to work with and I hope to do so again in the future.

Hey all. I’ve posted more detailed photos in the gallery here.

I don’t have one of the underside of the seat, Nathan; perhaps Jeff will be able to provide you one.