Anyone try a Torker giraffe yet? why so cheap?

[Sofa]

This sounds like a pretty good deal on the Torker Giraffes at uni.com.

Why are they so cheap?

Poor components?

Or is the consumer actually getting a good deal this time?


--
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[john_childs]

Is the new Torker giraffe using a threaded track style hub with the
sprocket threaded onto the hub and held in place by a lockring? From
the pictures that UniBrier 'posted'
(http://www.unicyclist.com/gallery/2004Torker) it looks like they're
using a threaded on sprocket down at the hub. I don't like giraffes
that have a threaded sprockets. It's not safe. I'd rather that Torker
designed a hub where the sprocket bolts onto the hub like Schwinn did on
their later model giraffes. The threaded on sprockets usually need to
be welded onto the hub to keep them from slipping and that is not an
ideal solution.

Maybe Torker has designed something that will keep the sprocket from
slipping. I'd have to take the sprocket off the hub to find out. You
can't tell from the pictures. But my guess is that the sprocket is
threaded on.

Other than that, the giraffe looks good. It's not professional quality,
but then you're not paying for a DM giraffe either.


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[ubersquish]

i'm not speaking from experience, but why are bolted on sprockets
superior? track racers spend uber money on their bikes, and if bolts
were better, that's what they'd be using, right?


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[johnfoss]

ubersquish wrote:
> *i'm not speaking from experience, but why are bolted on sprockets
> superior?*
The experience is to have the sprocket inscrew. Track bikes are only
pedaled in one direction. On a unicycle, we use all our strength to
change directions all the time. Threaded-on sprockets can be a lawsuit
in the making...


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John Foss, the Uni-Cyclone
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[bugman]

johnfoss wrote:
> *The 'experience' is to have the sprocket unscrew. Track bikes are
> only pedaled in one direction. On a unicycle, we use all our strength
> to change directions all the time. Threaded-on sprockets can be a
> lawsuit in the making... *


That's exactly what I was thinking. I am definitely buying one. If it
unscrews I am going to be rich! I hope they have good insurance.:D


--
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"Trying to maintain balance by wild arm and body motions is something
like trying to balance a wet noodle"
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[muniracer]

i dont think anyone could win a courtcase when their opening arguments
are:

"i was riding my unicycle down the street when..."


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[johnfoss]

muniracer wrote:
> *i dont think anyone could win a courtcase when their opening
> arguments are:
>
> "i was riding my unicycle down the street when..." *
In this country, any frivolous lawsuit is possible. Shattering your
elbow because your unicycle unscrewed on you while you were riding it
normally has happened, and probably could be actionable. I'm not
recommending this, but potential customers should be aware of
threaded-on sprockets if they have them.

I think I have one on my 9-footer (old Schwinn Giraffe hub). Not sure at
the moment, I'd have to look. In any case, I give the cycle a thorough
test, while holding onto something, before every ride. This one only
gets used in the occasional parade, so not many miles get put on it, but
those miles are high up in only semi-controlled situations.


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"jfoss" at "unicycling.com"
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[cyberbellum]

johnfoss wrote:
> *The 'experience' is to have the sprocket unscrew. Track bikes are
> only pedaled in one direction. On a unicycle, we use all our strength
> to change directions all the time. Threaded-on sprockets can be a
> lawsuit in the making... *

This isn't exactly true. Speed regulation for trackies is virtually
identical to unicycle balancing.

Unscrewing a sprocket on a track bike at speed is at least as bad as
falling from a giraffe. Probably worse. You're pretty high up when you
are on the bank, and all that kinetic energy has to go somewhere. Also
you're cleated down so there's no escaping the bike.

And trackies aren't weak - most of the elite sprinters can push at least
400-500 lbs with either foot. I can think of several races where I was
getting boxed in and needed to suddenly move back by a wheel length or
two to make my escape. I used full force to resist the pedal movement,
which meant that I was using a source of energy more powerful than my
legs.

There are two kinds of track hubs with lockrings. The first, and
DEFINATELY UNSAFE version has both the cog and the lockring threaded in
the same direction on the same set of threads. This system is sometimes
used on street fixed gears where the rider has brakes, so John's
assumption is valid. No amount of lock-tite or tightening will keep
this kind on the hub if the rider aggressively backpedals. It's ok for
mild speed modulation, but I'd never ride one.

The other kind, which is the only type approved for track use. The hub
has two sets of threads - a larger diameter one threaded in the normal
way so that the cog tightens against the hub when pedaling forward.
Just outboard of this set of threads the hub diameter decreases and a
second set of threads is cut which tightens in the opposite direction.
The lockring mounts on this second set of threads

The way to secure this setup is to first get the cog as tight as
possible (a couple of spirited accelerations usually does the trick),
then use a C-spanner to jamb the lockring against the cog. If the cog
tries to unscrew it tightens the lockring further. After a few good
sprints the lockring is tightened even further. No lock-tite required.


So, I don't know what method Torker uses, but I assume for safety sake
it's at least a real track hub properly installed. If it's not, if they
are using the poor-man's lockring, then I definately agree with John
that it's unsafe.


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[john_childs]

cyberbellum wrote:
> *The other kind is the only type approved for track use. The hub has
> two sets of threads - a larger diameter one threaded in the normal way
> so that the cog tightens against the hub when pedaling forward. Just
> outboard of this set of threads the hub diameter decreases and a
> second set of threads is cut which tightens in the opposite direction.
> The lockring mounts on this second set of threads
> *

That is exactly the type that Schwinn used on their first generation of
giraffes. It has two sets of threads with one of them threaded in the
reverse direction. It's not guaranteed not to unscrew on a giraffe.
Welding the cog to the hub is the only way to be absolutely sure that it
will not slip.

Schwinn's second generation of giraffes used bolts similar to lug nuts
to secure the cog to the hub. This style of hub will not slip and does
not need to be welded. Unfortunately Schwinn is no longer making
giraffes and you can no longer get that hub.

I was hopeful (and remain hopeful) that Torker would design a better
giraffe hub that will not slip. We need one because all of the giraffe
hubs available right now are the threaded track style hub. We need one
of the giraffe manufacturers to manufacture a hub that will not slip.
Something with a bolt on cog or splined cog or something else that will
prevent the cog from ever coming loose while riding.


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[joemarshall]

Ahem - bolt on conversion of a disc hub if anyone felt like making their
own for a giraffe.

http://www.63xc.com/jasom/milldisc.htm


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[Tmornstar]

As a very experienced, yet former, track racer I can attest that it is
possible to put a screw-on cog on a hub and not have is come off by
itself. You just need to put on the lock ring with the proper tool –
and grunt a little in the process. I think that the screw-on style is
better because you can actually get the cog off to rebuild the wheel
should the opportunity present itself. I’m for being able to fix
stuff.

Tommy


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Tommy Thompson
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[john_childs]

joemarshall wrote:
> *Ahem - bolt on conversion of a disc hub if anyone felt like making
> their own for a giraffe.
>
> http://www.63xc.com/jasom/milldisc.htm *

Wow! I like that!
That's the way giraffe unicycle hubs should be made, with the cog
bolting right to the hub like disk brake rotors do.

I doubt you could retrofit an existing giraffe with a hub like that. I
think the giraffe unicycle hubs are narrower than bike hubs. It might
be possible to find a bike hub with a disk brake mount that's the right
width to fit an existing giraffe frame. That would be cool. But then
there is also the issue of chainline. It would be pure luck if the
chainline remained all in line. Most likely the chainline will be off
and will have to be adjusted at the bottom bracket. Unfortunately most
giraffes don't have a bottom bracket that can be adjusted for changes in
chainline. But if you're building your own giraffe you can take all
those issues into account and make it all work with that retrofitted
bike hub.


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[U-Turn]

I'm for Tommy Morningstar's approach. It's much simpler and more
maintainable. John, do you have some stories which would say that
Tommy's approach is not the correct one? If so, how do you know the hub
and cog were installed correctly?

I'm currently working on two giraffes that have seen a lot of use and
haven't been welded. One is a 6-footer that the owner jump-mounts and
does 10+ mile rides on. I haven't heard a word about the hub giving any
problems.


--
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[john_childs]

U-Turn wrote:
> *I'm for Tommy Morningstar's approach. It's much simpler and more
> maintainable. John, do you have some stories which would say that
> Tommy's approach is not the correct one? If so, how do you know the
> hub and cog were installed correctly?
> *

Dustin Kelm has had problems with the cog spinning loose on his Semcycle
giraffe. He uses that giraffe for shows and some of his tricks put a
lot of back pressure on the pedals (for example, getting out of the side
ride). He was Loctiting the cog and lockring, but even that would
eventually work itself loose. I believe he now has the cog welded in
place.

I believe John Foss has also had the experience of a slipping cog while
up on a giraffe.

The cog can eventually slip even if the cog and lockring are installed
correctly. The big problem is that you can never be sure if it is still
tight until it slips, and at that time you're SOL. It's not a safe
design.

I have heard Darren Bedford say that he will never sell a giraffe that
hasn't had the cog welded to the hub.

I have a Semcycle hub on my Schwinn giraffe. The cog and lockring are
Loctited and they were installed very tightly. That works for me for
now but I am going to have the cog welded on one of these days
(hopefully before it ever slips on me).

I really like the sure-fire bolt-on cog idea. It will not slip. All
you have to do is make sure the bolts are tight and Loctited and the cog
will never slip. If you have to replace the cog or replace a spoke or
do other maintenance on the wheel you can easily remove the cog. It's
the perfect solution.

Bolting the cog on a disk brake hub is brilliant. Cheers to the guy who
thought of that.


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[johnfoss]

U-Turn wrote:
> *John, do you have some stories which would say that Tommy's approach
> is not the correct one?*
John #2 responds:

As experienced track racers, I have no dispute for what those guys are
saying about how track hubs work for mondo-powerful track racers.
Clearly if those designs were inferior for track bikes, they would be
changed. Track bikes are specialty items, and tend to be expensive
anyway.

In any case, the danger of a sprocket unscrewing on a giraffe is
potentially higher than in a track race. I'm guessing the danger in a
track race is a sudden loss of control, leading to possible tangling up
with other riders. If other riders are not nearby, the two-wheeled track
bike should be able to stay upright.

On a unicycle, without warning, the wheel will roll out from under you.
This can lead to a fall without warning, landing in whatever position
your body happens to be in. This is a lot worse than a UPD that you at
least have a second or two to prepare for.

Once upon a time, a friend and I purchased six old Schwinn Giraffes from
an elementary school in Ohio that was no longer using them. I then
resold them, but first took them to the bike shop to have the hubs
tightened because they were the threaded kind.

What followed is the main fuel for my mistrust of bike mechanics when
working on unicycles. I specified "red Loctite" to be used, and for them
to be tightened to the limits of their tools and skills. What I got was
green loctite, and a sprocket that unscrewed as soon as I tried to
rolling-mount it in the parking lot.

This was a well-known and popular bike shop, one of Long Island's
largest. With multiple mechanics on duty most of the time, unicycles
were probably always relegated to the lowest-level mechanics; the ones
that assemble new bikes or do other basic tasks. I was told green
Loctite was used because red was supposed to be permanent.

So I had to explain the job to them again, and wait again for it to be
done a second time. But rest-assured, even assembled by a popular bike
shop, one of those old Schwinn Giraffe hubs is still a potential
problem. The only worse things that can happen on a giraffe are frame or
chain breakage. You may get a little bit more warning with a loose
sprocket, if you're paying attention.


--
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John Foss, the Uni-Cyclone
"jfoss" at "unicycling.com"
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[U-Turn]

Thank you for the input, Johnx2. The one I am working on right now has
room for 2 lockrings; that plus red Loctite should be fine. The others
I will have to see what is available. Thanks again for some more
cognitive challenges!


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[john_childs]

U-Turn wrote:
> *Thank you for the input, Johnx2. The one I am working on right now
> has room for 2 lockrings; that plus red Loctite should be fine. The
> others I will have to see what is available. Thanks again for some
> more cognitive challenges! *

If you go with the Loctite, use the Loctite primer to clean the threads.
The primer will clean off grease, oil, and dirt and will let the
Loctite get a stronger bond.

The primer is an acetone based cleaner that also acts as an activator
that speeds and improves the curing. It will help guarantee that you
get the strongest possible bond with the Loctite threadlocker.


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[U-Turn]

Thanks for the comments, cyber. So far it seems as though the giraffes
I'm working with are of lower quality than the track components, and
they are not the best of the track components. Perhaps Dustin and other
top performers would do well to look into better hubs (if they are not
already) such as the Phil Woods which are running about $150 per hub.
The Surly track cog I just purchased for a giraffe appears to be very
strong and runs about $30 retail; with the lock ring running about $14.
So there may be issues behind these stories such as component quality
and installation procedure.

The most important thing to say is: learn to check your uni carefully
before you trust your life to it. That's a good habit for any sport.

> It's hard for me to believe that any unicycle rider has ever managed
> to get that much traction on a giraffe.
Except that you're forgetting that in a stop a bicyclist, whose weight
is distributed over two wheels, has perhaps 1/4 to even 1/6 of the
pressure on that wheel that a giraffe rider has. Since the coefficient
of kinetic friction for a rubber tire is far less than the coefficient
of static friction, it seems clear that a giraffe rider putting a couple
of g's on a lever arm, directly into the ground with no skidding, could
go way beyond a track bicyclist in terms of torque on the rear sprocket.


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[cyberbellum]

U-Turn wrote:
> *
> Except that you're forgetting that in a stop a bicyclist, whose weight
> is distributed over two wheels, has perhaps 1/4 to even 1/6 of the
> pressure on that wheel that a giraffe rider has. Since the
> coefficient of kinetic friction for a rubber tire is far less than the
> coefficient of static friction, it seems clear that a giraffe rider
> putting a couple of g's on a lever arm, directly into the ground with
> no skidding, could go way beyond a track bicyclist in terms of torque
> on the rear sprocket. *

Yeah, it's hard to say. When I really want to stop I slide back off the
seat to get as much weight on the rear wheel as possible, and try to
ride at immenent loss of traction. I'm a heavy guy - 220 lbs - and the
bike weighs about 20 lbs so there is probably 120 lbs or more on the
rear wheel when I really want to stop. (I normally have about a 60/40
weight distribution in level riding. By scooting back I change that to
a 70/30, but the decelleration moves some forward so let's call it a bit
less than 50/50.)

Dustin weighs what, about 160? With the giraffe about 200 lbs into the
ground? If he gets a 25 degree lean on his giraffe he's pulling about
1.09g's, which means a dynamic weight of 218 lbs. I still don't think
he comes anywhere near breaking loose - if he did he'd slide out every
now and then - but let's say he sometimes gets to 80% of max traction.
That means he's working with an equivalent contact pressure of 175lbs.
175lb*20" is about equal to 120lb*29", so yeah, it does look like
giraffe cogs get loaded up pretty high too. I'm convinced.

Bottom line is that good equipment properly installed is essential for
either one.

BOT, does anyone know if the Torker giraffe has a decent cog and hub?
As U-turn says, in the $30 sprocket/$15 lockring range on a hub with
decent threads?


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[john_childs]

cyberbellum wrote:
> *BOT, does anyone know if the Torker giraffe has a decent cog and hub?
> As U-turn says, in the $30 sprocket/$15 lockring range on a hub with
> decent threads? *

The cog on the Torker giraffe is just stamped steel. It's nowhere near
Campy or Surly quality. Think Wal-Mart quality and you're in the
ballpark.

There are pictures of the Torker giraffe 'here'
(http://www.unicyclist.com/gallery/2004Torker)
There are some spacers between the lockring and the cog. I don't know
what's up with that.

The problem we have with the cog coming loose on the giraffes is likely
due to poor component quality. I don't have any confidence that the
threads on the cog are carefully machined or held to a tight tolerance.
The hub may be of OK quality, but put a cheap cog and cheap lockring on
it and the combination is not so good. That may be why we have problems
with slipping cogs. We don't get Surly or Phil Wood or Campy quality in
our giraffe components.


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[U-Turn]

> *There are pictures of the Torker giraffe 'here'
> (http://www.unicyclist.com/gallery/2004Torker)
> There are some spacers between the lockring and the cog. I don't know
> what's up with that.*
It also looks as though the lockring doesn't have all its threads fully
engaged...

> *The problem we have with the cog coming loose on the giraffes is
> likely due to poor component quality. I don't have any confidence
> that the threads on the cog are carefully machined or held to a tight
> tolerance. The hub may be of OK quality, but put a cheap cog and
> cheap lockring on it and the combination is not so good. That may be
> why we have problems with slipping cogs. We don't get Surly or Phil
> Wood or Campy quality in our giraffe components. *
Coming soon to a traffic sign near you....


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[Tmornstar]

I like what I've read about the development of the bolt-on cog, secure
yet removable, a perfect solution. Another point to add to John’s
comparison to track riders, I was thinking that even the strongest track
rider my not apply the amount of torque (165mm crank to a 700cm wheel),
as that of a 20” wheeled giraffe. Obviously, a track bike is geared
more than a tad higher than a giraffe. I think that John is correct.
Even a non-athletic giraffe rider will apply more torque than a track
rider. (On the other hand, have you seen those tree-trunks coming out
of the shorts of some of those riders? Yikes!)


--
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Tommy Thompson
Memphis Unicycle Club
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[cyberbellum]

john_childs wrote:
> *
> There are pictures of the Torker giraffe 'here'
> (http://www.unicyclist.com/gallery/2004Torker)
> There are some spacers between the lockring and the cog. I don't know
> what's up with that.
> *

Thanks for the link to the photos. I fully agree with your assessment.


1) There should only be metal to metal contact. The photo shows paint
on the cog. Having this spongy material between the cog and the locknut
is just wrong.

2) The lockring appears to be a complex shape in the photo. I can't
tell if those are washers or the actual lockring, with the visible part
of the lockring just a fitting for the spanner. If those really are
spacers then I'm totally baffled.

3) The lockring threads are showing. Yiiikes!!

K-mart quality is unsafe at any speed. I wouldn't ride it without
modification.


Tmorningstar: It doesn't matter how the torque is applied to the cog,
the limiting factor is wheel slip. When the tire is near the limit of
adhesion then the cog is putting the maximum torque the wheel can
sustain into the hub.

Yeah, those guys have big legs. They're typical "track beasts" -
fast-twitch guys who hang out in weight rooms and can sprint up to 45
mph for 10 seconds. The other kind of track rider, fast roadies that
look almost normal, can't go as fast but they can sustain 30+ mph for
5-10 minutes at a time. In either case, human muscles aren't strong
enough to spin the tire past the limit of adhesion once they are moving.
(I've heard track beasts "burn rubber" at up to 40 mph, but they were
unweighting the rear wheel by the violence of their sprint. The faster
guys are virtually silent because they know how to keep the tire down.)


Decelerating can slide the wheel at any speed because the rider can
"lock up" his legs. Since trackies are tied down on their pedals they
can resist with both legs - the back foot pushing down and the front
foot pulling up.

The equivalent idea in this forum is crank bending. How many people
could bend a set of cranks with muscle power alone? No one, not even
the track beasts. Yet teenagers in this forum are routinely bending
cranks by landing big drops.


--
cyberbellum - Level 0.5 rider

AA, AAA and AARP are thinking of merging into one large organization
that represents old drunk drivers...
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[nikkifrog]

What do you think about the new Nimbus giraffe?

http://www.unicycle.com/shopping/shopexd.asp?id=747

Nikki


--
nikkifrog - Officially Level 2! :)

"When I am afraid, I will trust in you. In God, whose word I praise, in
God I trust; I will not be afraid. What can mortal man do to me?"
Psalm 56:3-4
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[Klaas Bil]

On Fri, 5 Dec 2003 09:56:05 -0600, cyberbellum
om> wrote:

>Tmorningstar: It doesn't matter how the torque is applied to the cog,
>the limiting factor is wheel slip. When the tire is near the limit of
>adhesion then the cog is putting the maximum torque the wheel can
>sustain into the hub.

I may have missed it (I haven't read too thoroughly) but don't forget
to take wheel diameter into account. Giraffe wheel is probably
smaller.

Klaas Bil - Newsgroup Addict
--
"Friends don't let friends drop to flat - Kris Holm, discussing large drops to flat ground."

[U-Turn]

> Tmorningstar: It doesn't matter how the torque is applied to the
> cog,
> >the limiting factor is wheel slip. When the tire is near the limit
> of
> >adhesion then the cog is putting the maximum torque the wheel can
> >sustain into the hub.
>
> I may have missed it (I haven't read too thoroughly) but don't
> forget
> to take wheel diameter into account. Giraffe wheel is probably
> smaller.
cyber mentioned that a few posts up, Klaas. As well, the pressure on
the surface is important. Remember that the frictional force is
dependent on the properties of the tire and of the surface, and also the
pressure on that surface. Exiting a sideride, a giraffe move mentioned
above, would result in a significant downwards pressure on the wheel
(especially in comparison with a bicycle stop) which increases the
torque on the cog while simultaneously decreasing the tire's tendency to
slip on the surface.


--
U-Turn - Wholly Roller

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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[cyberbellum]

U-Turn wrote:
> *
> Exiting a sideride,...
> *

What is a side ride? I did a google search and found only that it was a
level 10 skill. No description.


--
cyberbellum - Level 0.5 rider

Optimists think the glass is half full. Pesimists think the glass is
half empty. Engineers think the glass is too big.
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[Mark Newbold]

I'm opposed to welding the cog to the hub because it's interesting to try
out different cogs. I don't much like a giraffe that has a 1-1 gear ratio
because I feel like I'm moving in slow motion up there.

My 6-footer has 20 teeth on top and 17 on the bottom, with a 20" wheel.
Effectively a 23.5 inch.

My 4.5-footer has 20 teeth on top and 18 on the bottom, with a 24" wheel.
Effectively a 26.5 inch.

Both configurations feel pretty sweet, though a fall from the 24" giraffe
"at speed" is not pleasant.

Another issue is if you have to replace a spoke, you're going to want to
take the cog off. Maybe you can fiddle a single spoke through if you have
to. But what if you want to replace the whole rim?

I hesitate to contradict the more experienced voices in this thread but it
seems to me that a reverse-threaded lockring is pretty safe. As long as the
lockring is tight against the cog it isn't going to come loose all at once.
At first you will just notice some extra slop when it starts to come loose.

Of course if the lockring manages to work itself loose while the cog is
still tight, then the cog could come loose catastrophically. I'm can't think
why that would happen, but if you were worried about it, I would recommend
visually inspecting it frequently.

On mine I have to get the chain out of the way to tighten the lockring, so
it isn't practical to snug it up before each ride. Not that I would bother
anyway. The tightening notches in the lockring are easily damaged.

I suppose there are ways to weld the cog to the hub that would allow removal
of the cog if necessary. Maybe just weld in a few spots. Then you could
grind the weld out if necessary.

--Mark

--
Mark Newbold
Shelburne, Vermont USA
http://dogfeathers.com

[U-Turn]

cyberbellum wrote:
> *
> What is a side ride? I did a google search and found only that it was
> a level 10 skill. No description. *
I don't know any web vids, but you can see it in OWNL and on Unizaba.
It's basically having your whole body on one side of the unicycle,
facing forwards. You pedal with the foot nearest the uni and support
your weight with your hands on the seat. The other leg flies around in
the air keeping your balance. I can't do it... yet....

I agree with Mark. Perhaps the standard track hub locking ring is not
the perfect approach, but it should be possible to redo the wheel
without a grinding machine, but still maintain a secure attachment. It
also should be possible to continue to leech off the bicycling world and
use a standard track hub; perhaps we need to come up with our own
locking mechanism.


--
U-Turn - Wholly Roller

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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[john_childs]

cyberbellum wrote:
> *
> What is a side ride? I did a google search and found only that it was
> a level 10 skill. No description. *

There aren't very many online photos or videos of the side ride. Klaas
has a short QuickTime video of Sem Abrahams doing a side ride. 'Klaas'
Sem videos' (http://www.xs4all.nl/~klaasbil/sem_teresa.htm)

Now imagine doing that on a 6' giraffe and transitioning in and out of
the side ride. It's amazing. And Dustin makes it look so smooth. The
side ride is the main skill, but it's the transition in and out of it
that is the really impressive part.


--
john_childs - Guinness Mojo

john_childs (at) hotmail (dot) com
Gallery: '' (http://www.unicyclist.com/gallery/john_childs)
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[UniBrier]

Back to the original question about the quality of the Torker Giraffe.

I took another look at two assembled unis. Both had a definite "loose"
and "tight" spot in the chain as the crank does a full revolution. It
appears the lower cog is slightly off center, probably less than 1 mm.
It is not uncommon to have somewhat of a tight spot but I found this
greater than other giraffes. The chains weren't tensioned very much so
there was quite a bit of slack at the loose spot.

Also, at the bottom of the frame, where the frame legs are pinched down
by axle, a separate piece of metal is welded into the frame. You can see
it in the 'profile pic '
(http://www.unicyclist.com/gallery/2004Torker/PICT3436) and 'lower
bracket pic' (http://www.unicyclist.com/gallery/2004Torker/PICT3435) .
On other giraffes I have seen (Schwinn, TUF, Matthews, Savage) the
entire lower frame leg is pinched flat and a groove is cut for the axle
like on the 'Schwinn here.'
(http://www.unicyclist.com/gallery/albun48/aae) This may not be a bad
thing, but it is different than most other giraffe designs.

My opinion so far is the Torker is a medium quality giraffe. Probably
fine for light riders but before I would put someone big on it or
consider it heavy duty I would want to know more about the sprocket
attachment and how the stamped steel componets are going to hold up.

Maybe Uni.com can take one of the sprockets apart when their shipment
comes in and give us a report for the good of the order.


--
UniBrier - Its Time to Ride

Steve DeKoekkoek - I've got a one track mind.
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[cyberbellum]

UniBrier wrote:
> *
> Also, at the bottom of the frame, where the frame legs are pinched
> down by axle, a separate piece of metal is welded into the frame ...
> On other giraffes I have seen (Schwinn, TUF, Matthews, Savage) the
> entire lower frame leg is pinched flat and a groove is cut for the
> axle.
> *

Now I understand the need for a chain tensioner.

Track bikes don't use these things because at the end of the stays there
is a honking big slab of metal for the track nuts to bite into - it's
usualy 'a slab of steel about an 1/8\" thick' (http://tinyurl.com/y2kv).
Those presed stay ends look really flimsy to me. I doubt they would
survive the kind of tightening a track bike regularly endures.


--
cyberbellum - Level 0.5 rider

Optimists think the glass is half full. Pesimists think the glass is
half empty. Engineers think the glass is too big.
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