these aren't supposed to break

[shadowuni]

well, i was out riding today, and i did some uni-spins, some one foot
and two foot wheel walking, and practiced some hop-on-wheel. about 20
mins later, while holding my wheel, i notice something odd. one of my
spokes is broken! "what the heck?" i ask, but i figure i can still do
some mild tricks and ride it home. i did make 24" before it broke, but
maybe that caused it to break.....i dont really know. that wasn't
even the worst part/

later on it was dark out, and as i was hanging out with my friends, i
saw a small 3-set, and decided to 180 over it. i rode, jumped, twisted
90 degrees and fell. why did i fall? because my SEATPOST BROKE. i
thought those were hard to break. i was using the 350mm x 25mm? that
comes with the stock KH 20" trials, and it broke at the weld. i was sad
that it broke, but not dumbfounded by where it broke. i ask Kris Holm
this question, "why does the seatpost taper down at the weld? doesn't
that make that one spot really weak?" the post gets thinner at the
weld. bad stuff that was my day.

Optimists say: you improved on your one foot wheel walk and you hopped
24" today!
Pessimists say: you definitely broke a spoke and your seatpost. the
spoke will be hard to find, while the seatpost is out of stock!
I say: long day


--
shadowuni - Level 5.5 Unicyclist

"No one is taller than the last man standing"
"Freeze, Mother Stickers! This is a F**k up!" - Stupid Criminal

"unless I'm catastrophically off-balance, in which I'll have to hop to
stay up." - gerblefranklin
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[johnfoss]

I've killed many a seat post over the years. Mostly Miyata posts, which
were made out of low grade steel. I don't think I ever broke one at the
weld; the actual metal would rip from repeated seat flexing.

Today's unicycle seat posts are subjected to way more stress than their
original designs were intended for. Nobody expected, years ago, for
riders to be doing what we're doing, let alone yanking and squashing on
the front of the seat. Adding an extended handle to that makes the
problem worse. So sometimes the seat breaks, and sometimes it's the
post.

Over the years I've had several gusseted seat posts made, to make the
seat/post joint more strong and rigid. This preserves the life of both
the seat and post, and also gives you better power transmission because
there is no flex in that area. This was most useful on my old track
uni.

I believe future high-end unicycles will have lighter-weight seats, and
handles that are built into the posts, so the seats don't get stressed.
This should allow for more overall lightness (assuming you need a strong
handle) and less breakage.

Hard to find spoke? Many bike shops have tools to cut and thread spokes
to whatever length you need. When I get wheels built (or rebuilt) I
always order a few extra spokes to save hassles when I have to replace
one. The hard part then is finding the right spoke several years later
when I need it...


--
johnfoss - Walkin' on the edge

John Foss, the Uni-Cyclone
"jfoss" at "unicycling.com"
www.unicycling.com

"I should be wearing a helmet here -- so should you." -- George Peck,
who almost never wears one, in the 1991 video Rough Terrain Unicycling
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