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Rowan
August 26th 03, 02:28 PM
Yesterday, Mike who is better at hopping than riding had a go on my
Wilder MUni. He jumped over some mags with a plank balanced on them. I
was pleased to see how impressive his hops were, even though he wasn't
riding away from them. As I was riding home I was surprised by how flexy
the Kris Holm Velo saddle felt. Upon closer inspection Mike had snapped
the seat in the middle. There was no metal plate, and Mike's
jackhammer/pogo style learner hopping was too much for the flexible
plastic. I'd say it was a combination of bad design and bad technique. I
have heard of a method to fix this problem with a brace thing, but I
have another temporary solution : to build an Air-saddle. I have to wake
up early tomorrow to drill out holes for the Reeder handle. Also I am
wondering about what bumpers fit on carbon fibre bases, and if most
people use them or what. I am considering getting a Kinport rear bumper.


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Rowan - .`.
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U-Turn
August 26th 03, 07:21 PM
The Miyata rear bumper is more leg-friendly than the Kinport, but you
can trim the Kinport somewhat. If you wear Cordura riding shorts, that
helps a lot with the Kinport, which is much cheaper to obtain than a
Miyata.

You should definitely use a rear bumper. WIth a Reeder handle, the
front bumper is not desirable.

In addition, recent developments suggest using a couple thicknesses of
thick DH inner tube between the seat adapter and your CF base to help
spread out the stress areas that exist at the edges of the adapter.

I recently rebuilt mine and have pics, but haven't posted any yet.
Here's one, though, that shows the rubber insert on the adapter. You
should also use one on the Reeder handle - CF interface.


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U-Turn - Mounting a Revolution

Weep in the dojo... laugh in the battlefield.

'Strongest Coker Wheel in the World'
(http://www.unicyclist.com/gallery/albup39)

-- Dave Stockton
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U-Turn
August 26th 03, 07:24 PM
This shows the insert for the Reeder handle.


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--
U-Turn - Mounting a Revolution

Weep in the dojo... laugh in the battlefield.

'Strongest Coker Wheel in the World'
(http://www.unicyclist.com/gallery/albup39)

-- Dave Stockton
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Rowan
August 26th 03, 08:43 PM
Thanks for the replies and the advice U-turn. That picture looks like a
Wilder rails adapter, the Kinport one has no brake mount. I get the idea
conveyed by the pictures though. I already intended to use some inner
tube rubber after seeing the broken CF seat, is one layer of rubber not
enough for protection? I want it to cushion the edges but not be enough
to flex when I pull on it. I will consider getting the leg-friendly
Miyata bumper (maybe someone has a spare one), or else I could get that
kinport one because at least they make it in black. I just had an idea
that I could temporarily strap some innertube rubber to the back of the
seat for the meanwhile. I should be finished the rest of the airseat
today, and I haven't even ordered a bumper yet. It will be hard not to
split the leather if I don't have protection.

I had a go yesterday on my Airseat with a long seatpost. It felt amazing
to ride up a gutter, and I could feel the unicycle compress at both
ends! I was also impressed that my Thomson seatpost defeated my pipe
cutter last night. I'll have to hacksaw it because the pipe-cutter blade
kept getting stuck, and would not delve deep enough.

Does anyone know if the dust from drilling/sanding carbon fibre seats is
hazardous? I read something on the net about carbon fibre dust being
dangerous to breath if the fibres are so many microns across or long,
but I wouldn't have a clue as to how many microns each fibre is. I have
been drilling in the Polytech workshop, and I was wearing breathing and
eye protection, but Todd behind me reckoned I poisoned him with my
fumes. The tutor thought it would only be dangerous if you inhaled it
all the time (and wasn't going to supply me with a dust mask). It's fun
to drill the Carbon fibre seat base, I am glad the holes line up well
enough so far after I did it myself.


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Rowan - .`.
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U-Turn
August 26th 03, 11:33 PM
The extra layer of rubber is heavier, to be sure. I just figured it
would round out the stress edges more. There doesn't appear to be any
flex anywhere in the seat or handle.

You could drill a hole on the back edge and install a rubber "foot"
about 1" in diameter, sticking straight out the back. Even better would
be one on each back corner as well. This temporary fix would not affect
the saddle strength and would help immensely with UPD damage. Get the
feet at the local hardware store.

For the best protection, though, especially off-road in rocks and the
like, the back bumper would be ideal. The back bumper would cover up
any holes you have drilled, in the CF or in the leather.

Maybe your buddies at uni.com.nz would have a couple of Miyata seat
seconds kicking around that you could buy the back bumper off of.

If you have any concerns at all about fibers simply wear breathing
protection. It's not worth a lifetime of respiratory problems to mess
with.

Good luck with the rest of your project, Rowan!


--
U-Turn - Mounting a Revolution

Weep in the dojo... laugh in the battlefield.

'Strongest Coker Wheel in the World'
(http://www.unicyclist.com/gallery/albup39)

-- Dave Stockton
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