new Fury RoadMaster test
carl...@comcast.net
in technical questions should skip to the end for a picture
and a question.
Wheeling it away from where it sleeps with one pedal up on a
wooden picnic bench, I heard an odd sound.
Rolling it back and forth revealed that the sound came from
the rear wheel at one particular point.
Brakes? No, the pads weren't touching the rim.
Tire rubbing against the frame? No, there was room for a big
rat to crawl through between the tire and the chain stays or
seat stays when the noise was heard.
Something caught in the plastic spoke protector? No, it spun
freely.
A mechanical disaster inside the freewheel or--
Oh. I see. The massively treaded rear tire is almost flat.
The noise comes when a section of the bead that's almost
loose rolls under the hub and gets squeezed back against the
rim.
The Fury is flipped onto its back with its thumb-shifters
and speedometer held off the back porch concrete by a wooden
2x4 frame (nothing is too good for a high-quality bicycle).
An adjustable wrench loosens the axle nuts, and out comes
the rear wheel.
Hmmm . . . a bit heavier than my touring bike's wheel.
A thumbnail depresses the Schrader valve enough to let the
rest of the air out and the monster tire comes off the rim
quite easily.
Odd, nothing stuck in the tire, rim strip in place, no
apparent hole in the tire. It's almost sunset, so to hell
with it for now.
One of three spare 2x26 tubes bought on sale goes in and the
tire goes back on the rim almost as easily as it came off.
After a brief introduction to Mr. Air Compressor, the tire
seats nicely and--
D'oh! When inflated, gargantuan treaded tires do not slip
past the brake pads. Thumbnail adjustment of the air
pressure eventually reduces the stiff and swollen tire
enough for its return to its rightful place, followed by
another CPR session with the air compressor.
After an uneventful ride, the suspect tube is placed in the
dunking stool of the kitchen sink and quickly found guilty.
A tiny stream of bubbles leaks out from underneath an odd
gash--a flap, really--on the edge of the circle where the
valve stem attaches to the tube.
The tire went flat overnight after over 160 four-mile rides,
so whatever created the tiny flap happened yesterday, but
the rim strip was in place.
Closer examination shows that the rubber seems to have
split, bursting from the inside and peeling up a tiny flap
roughly over one spoke hole next to the valve.
Viewed in profile, little bulges appear on either side of
the inner tube's valve stem. Further away, around the inside
of the tube, are a few more odd bulges.
They seem to be centered over the spoke heads, with a dent
in the tube where it sat on the spoke head and a bulge on
either side. Here's a picture of the clearest example:
http://home.comcast.net/~carlfogel/download/tubebump.jpg
The spoke head was under the "in" of "Shin" and the shiny
bumps on either side are protruding. Most of these marks
amount to little more than scuff marks.
Why are there raised bumps on either side of the inner tube
where it sits on the spoke head? Why does the rubber distort
like this?
Carl Fogel
Warren Block
> They seem to be centered over the spoke heads, with a dent
> in the tube where it sat on the spoke head and a bulge on
> either side. Here's a picture of the clearest example:
>
> http://home.comcast.net/~carlfogel/download/tubebump.jpg
>
> The spoke head was under the "in" of "Shin" and the shiny
> bumps on either side are protruding. Most of these marks
> amount to little more than scuff marks.
>
> Why are there raised bumps on either side of the inner tube
> where it sits on the spoke head? Why does the rubber distort
> like this?
If it was a box section rim, I'd suggest a deformation of the rubber
where it stretched down into the spoke hole.
Nasty, cheap rubber rim strips, right? On another bike, it'd be worth
replacing them with cloth or nylon rim strips. For this bike, the old
strapping tape trick is probably more appropriate.
--
Warren Block * Rapid City, South Dakota * USA
Werehatrack
>Closer examination shows that the rubber seems to have
>split, bursting from the inside and peeling up a tiny flap
>roughly over one spoke hole next to the valve.
It might be interesting to see a pic of the rim in that area. I may
just peel the tire on a Roadmaster out back to see what's likely to be
going on.
>Viewed in profile, little bulges appear on either side of
>the inner tube's valve stem. Further away, around the inside
>of the tube, are a few more odd bulges.
>
>They seem to be centered over the spoke heads, with a dent
>in the tube where it sat on the spoke head and a bulge on
>either side. Here's a picture of the clearest example:
>
> http://home.comcast.net/~carlfogel/download/tubebump.jpg
Yup, that looks like the classic long-term-squirm that I've been
seeing for many years on tubes taken from wheels whose rims have
non-recessed spoke heads. Does your Fury have those really thin rim
bands?
>The spoke head was under the "in" of "Shin" and the shiny
>bumps on either side are protruding. Most of these marks
>amount to little more than scuff marks.
The fact that this is a low-bidder tube may have some bearing on the
results.
>Why are there raised bumps on either side of the inner tube
>where it sits on the spoke head? Why does the rubber distort
>like this?
I called it "long-term-squirm" above because that's the best
description I could come up with. The spoke head's "bump" in the rim
band causes a stretching on each side which doesn't fully settle in
right away; instead, when the tube is first inflated, the band
partially bridges from the nipple's shoulder o the rim interior, but
as the tire sits inflated, the band deforms to hug the shoulder, and
the tube deforms with it...outward, into the crevice, producing a bump
on the tube.
Check the tension of the spoke at that position. It may be a trifle
loose.
FYI, yet another Roadmaster (a Mt Climber this time) fell into the
pile a couple of weeks back; my daughter says it's got good gearing
but horrible brakes and an atrocious seat. Since the Roadmasters are
pretty much the only mountain bikes that the thieves didn't take when
I was hit a little over a week ago, I have decided that all of my
mountain bikes will be getting Roadmaster decals...when I have some
mountain bikes worth riding again, anyway.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.
David Reuteler
> Nasty, cheap rubber rim strips, right? On another bike, it'd be worth
> replacing them with cloth or nylon rim strips. For this bike, the old
> strapping tape trick is probably more appropriate.
i suggest putting it out of our misery. use slugs. post pictures.
--
david reuteler
reut...@visi.com
carl...@comcast.net
Dear Warren,
I'm afraid that I don't follow you, or perhaps you've
misunderstood me--sorry if I didn't make things clear.
The Fury RoadMaster's spokes stand proudly above the
inside of the rim, fearlessly facing the inner tube's
pressure instead of cowering in holes like certain modern
rim designs that I scorn to mention, cowards that huddle
under the surface of the rim and hope that the roof holds.
A handsome gray rubber rim strip (all the ones that I'd seen
before this were black) protects the inner tube from the
rugged contours of the Fury's spokes. This strip is in place
and undamaged.
As far as I can tell, neither nylon nor cloth nor strapping
tape would offer more protection than what are customarily
suits of solemn black. The well-tensioned spoke heads bulge
up through any reasonably thin material and are somehow
deforming the bejesus out of the inner curve of the inner
tube, here and there.
Carl Fogel
Warren Block
> The Fury RoadMaster's spokes stand proudly above the
> inside of the rim, fearlessly facing the inner tube's
> pressure instead of cowering in holes like certain modern
> rim designs that I scorn to mention, cowards that huddle
> under the surface of the rim and hope that the roof holds.
Crappy non-box-section rim, check.
> A handsome gray rubber rim strip (all the ones that I'd seen
> before this were black) protects the inner tube from the
> rugged contours of the Fury's spokes. This strip is in place
> and undamaged.
Ultra-cheap rubber rim strip, got it.
> As far as I can tell, neither nylon nor cloth nor strapping
> tape would offer more protection than what are customarily
> suits of solemn black. The well-tensioned spoke heads bulge
> up through any reasonably thin material and are somehow
> deforming the bejesus out of the inner curve of the inner
> tube, here and there.
Years back I found that sharp edges in a rim could cut through rubber
rim strips. Don't recall any visible holes in the rim strip; maybe a
sharp edge can cause a pinch flat in the tube without leaving a cut in
the rim strip. Strapping tape should have enough strength to keep the
tube from getting pinched by the nipple screwdriver slot, and, unlike
Velox rim strips, won't be worth more than the wheel it's on.
Sorry, let me rephrase that to match the thread:
Strapping tape may hold a lowly position in the stratified realms of
cycledom, yet its noble--and humbly silent--strength can resist the
relentless pneumatic butyl imposition where the dignified gray rim strip
would politely bow to pressure. Traditional rim strips would be gaudy
and financially inappropriate for the transportational marvel you've
described, but humble strapping tape will not embarrass.
carl...@comcast.net
Dear Warren,
While I admire your enthusiasm for mightier methods of
covering spokes, I have to clarify things to make sure that
the lowly rubber strips are not the victims of a
misunderstanding.
The tube didn't pinch or puncture over the spoke head.
The odd bulge to one side of the spoke head dent burst
outward, possibly because this particular bulge was in the
stiffer round reinforced section around the valve stem.
It isn't even a true burst in the sense of a star. There's a
roughly triangular flap and presumably a tiny leak lurking
under the base of the flap.
Here's a profile view:
http://home.comcast.net/~carlfogel/download/tubebump2.jpg
To the right of the valve stem you can see the tongue of the
tiny flap sticking up on the near side of the odd bulge. To
the right of the flap is the peak of the odd bulge. The
spoke-head mark is to the right of that peak.
In other words, the spoke-head was on the far side of the
bulge from the flap. Something about the inner tube didn't
like being forced into that odd bulge and burst along the
edge where the circle of reinforced rubber around the valve
stem stops.
Carl Fogel
Werehatrack
wrote:
>Sorry, let me rephrase that to match the thread:
>
>Strapping tape may hold a lowly position in the stratified realms of
>cycledom, yet its noble--and humbly silent--strength can resist the
>relentless pneumatic butyl imposition where the dignified gray rim strip
>would politely bow to pressure. Traditional rim strips would be gaudy
>and financially inappropriate for the transportational marvel you've
>described, but humble strapping tape will not embarrass.
You *did* use purple electrons to compose that, right? ;>
In years gone by, I found that tube failures on such rims could be
reduced by using two rim bands; one punched to go around all of the
spoke heads, and the other covering them. The holey band went on
first, then the unholey one. I haven't ridden many miles on a bike
with rims that needed such subterfuges since my days of pitching
newspapers from an EA-3-equipped 3-speed, but I used the trick to good
advantage back then. (I also seldom rode a tube that didn't have at
least three or four patches on it.)
Trevor Jeffrey
carl...@comcast.net wrote in message ...
>
>Why are there raised bumps on either side of the inner tube
>where it sits on the spoke head? Why does the rubber distort
>like this?
Because that's the way of the world.
Trevor
jim beam
carl, just file away the part of the spoke that protrudes above the
nipple head, then use a thick cloth rim tape - it's really the best you
can do without moving to a decent box section rim. a better quality
tube might help too - that rubber has clearly crept. when seeking an
alternative, bear in mind that most tubes these days come from similar
factories to the one yours came from, regardless of the fancy name on
the box.
i'd also suggest moving to a decent wheelset, but i know the roadmaster
is a project for you.
Trevor Jeffrey
the end, available from a bike shop near me, and most probably elsewhere.
The proprietor swears by them, usually when he's banged his head on the BMX
chainring hanging above the home of said rim tape. Have no definitive
description other than rim tape afaik. He also reckons on using moped
chains as the economic and safe choice for single speeds. He has otherwise
had returned machines due to 'snapped chains' and so routinely changes
chains on new bmx machines.
Trevor
carl...@comcast.net
Dear Jim,
I may still be failing to make things clear, so here's a
diagram for fixed-font.
valve
| | bulge1 bulge2
| | _ - _ spoke nipple _ - _
| |___ * - _ dent _ - - _ _ _
- _ -
* burst
I should have said "spoke nipple" dent instead of "spoke
head" dent--the heads of the spokes do not protrude at all
from the nipples.
Carl Fogel
dianne_1234
>>carl...@comcast.net <carl...@comcast.net> wrote:
>>
>Here's a profile view:
>
> http://home.comcast.net/~carlfogel/download/tubebump2.jpg
Dear Carl,
Excellent photograph!
Judging from the shape of the distended inner tube walls, and the fact
that the burst appears to "point" towards the valve, and the fact the
burst is very near to the edge of the rubber around the valve base, I
suspect neither spokes nor rim tape have anything to do with your
damaged tube.
It seems likely that the burst might have been caused by something
like the following scenario:
1. The valve might have been pushed into the interior of the tire
before or during initial inflation (perhaps at the 'Mart, maybe even
due to the force of the chuck on the valve).
2. This would have raised the reinforced valve base off the rim floor,
3. creating a gap between the valve base and the rim.
4. Then maybe the thinner and more flexible walls of the inner tube
stretched toward the valve stem in an attempt to fill this gap.
5. Once stretched, the tube might have slowly begun to distend
until...
6. One day it stretched too far, couldn't hold the air any longer and
burst. (It might take some time to develop permanently distended inner
tube walls).
Does that seem to make sense? Of course, I could be completely
wrong...
Benjamin Weiner
> Yikes! Disaster struck the Fury RoadMaster! Those interested
> in technical questions should skip to the end for a picture
> and a question.
> http://home.comcast.net/~carlfogel/download/tubebump.jpg
>
> The spoke head was under the "in" of "Shin" and the shiny
> bumps on either side are protruding. Most of these marks
> amount to little more than scuff marks.
>
> Why are there raised bumps on either side of the inner tube
> where it sits on the spoke head? Why does the rubber distort
> like this?
Carl,
The vast majority of Fury Roadmaster riders grace their tubes
with the embrace of a pump-chuck at intervals roughly equivalent
to those of Olympic years (Summer variety). Your regular
application of a brutish air-compressor to the Fury Roadmaster
is surely stressing the components well beyond their design limits,
deforming the tubes to the shape of their crudely constructed
pressure vessel.
Ride the bicycle no more. It may explode at any moment.
Werehatrack
wrote:
>Carl,
>
>The vast majority of Fury Roadmaster riders grace their tubes
>with the embrace of a pump-chuck at intervals roughly equivalent
>to those of Olympic years (Summer variety). Your regular
>application of a brutish air-compressor to the Fury Roadmaster
>is surely stressing the components well beyond their design limits,
>deforming the tubes to the shape of their crudely constructed
>pressure vessel.
>
>Ride the bicycle no more. It may explode at any moment.
You, sir, are getting entirely too good at Fogeling.
Practice makes perfect. Don't stop now.
carl...@comcast.net
(Benjamin Weiner) wrote:
Dear Benjamin,
Your warning falls too late upon deaf ears--166 rides,
673.96 miles, one flat tire, and dozens of terrified geese
scuttling off the road in the City Park.
However, you may have hit upon an explanation for the oddly
irregular bumps on either side of the nipples, with many
areas showing little beyond scuff marks.
It could be that the plump inner tube has trouble expanding
down into the deep, narrow well of the rim and that in some
places the mere 55 psi recommended fails to push the tube
firmly against the bottom of the rim.
Hmmm . . . maybe I need to try higher pressures?
Carl Fogel
carl...@comcast.net
Dear Dianne,
Your compliment on the photography is appreciated.
Here at Fogel Labs, only the finest $15 WalMart USB cameras
are used, clipped onto an 18-inch wooden ruler clamped into
an otherwise idle machinst's angle vise.
Your idea that the valve stem may have been holding the
inside of the inner tube away from the rim strikes me as
quite sensible--otherwise, the rubber could not have burst
outward.
(I'm not at all jealous that you thought of this and that I
didn't. Not at all.)
In addition to the valve stem possibly jamming a little and
holding the tube up, the well for the spokes in the Fury's
broad rim is deep and narrow, so the inner tube could have
some trouble squashing down far enough to touch the metal at
the very bottom, where the tiny burst occurred.
The stiffer round area around the base of the valve stem
would have also helped hold things away from the rim, just
as you suggest.
Green-eyed,
Carl Fogel
jim beam
the bulges are entirely consistent with where the material will stretch
most. decent rim tape will minimize the sharpness contour the tube
experiences and a decent tube will not creep as much.
carl...@comcast.net
wrote:
The Fury RoadMaster has outlasted its first speedometer, one
of several inexpensive Nashbar devices bought to save time
swapping things and to avoid remembering the quirks of
different instruments.
The speedometer still functioned, but the display took to
playing optometerist games, making 0's look like 8's and 6's
unless viewed just ever so--and sometimes even then.
Alas, the exact same model may no longer be available
(though what really matters is the mount and cable). And
prices have climbed to around $15, a serious consideration
for the $57.71 level of racing bicycle.
WalMart to the rescue!
I spotted a handsome red Schwinn speedometer for $9.95 and
promptly bought it. It comes with an elaborate mount that
can be adjusted to avoid using the speedometer as a prop
when flipping the bike upside down, a nice touch. The mount
also looks as if it engages the two contacts more securely
than the other models.
The Schwinn speedometer seems to have the same plethora of
functions (12) as the other models, but what won my heart
after I hooked it up and took it for a test ride up and down
the street was that the resettable odometer reads in
thousandths of a mile--at last, no more crude measurements
accurate to only the nearest 53 feet!
It's a bit startling to glance down and see the trip meter
changing so fast, so precisely, and in such tiny increments,
almost like switching from a 1970's typewriter to Microsoft
Word for printing memos.
If the Schwinn works well, I may replace the aging Nashbar
on my road bike.
Carl Fogel
carl...@comcast.net
wrote:
The off-set mount can be centered dead ahead of the stem
from either side--how nice!
And speed is shown in tenths of a mile per hour, rather than
the roughly half-mph increments on other inexpensive
speedometers!
Now if I can just figure out how to attach one to a basset
hound for precision walks . . .
Carl Fogel
carl...@comcast.net
WalMart now offers stiff competition to the Fury RoadMaster;
http://www.walmart.com/catalog/product.gsp?product_id=882808#long_descr
Like the Fury RoadMaster, the 26" Men's RoadMaster Sport SX
Mountain Bike is just under $60 and features the
"high-tensity steel" frame that captivated so many posters.
But it boasts numerous improvements!
There are 18 speeds now instead of only 15.
A water bottle and cage increase wind drag.
A fantastic new front suspension system is connected to a
fork that looks positively fragile compared to the old
"oversized" plumbing pipes.
A "NEW seat clamp" presumably addresses the embarrassing
sinking-seat-post problem mentioned months ago.
"NEW soft rubber grips" have replaced the adamantine devices
protecting the ends of the handlebars.
The "NEW riser handlebar for proper riding position" might
be high enough that I'd no longer look like Benny Hill on a
tricycle.
Ominously, the shipping weight has increased from 40 to
44.51 pounds.
I suppose that I now own a "classic" Fury RoadMaster that
will be the envy of the other kids on my block as they pedal
soullessly along on their dainty new Sport SX models.
Somewhere around Guy Fawkes Day, I plan to invest in a pair
of lightly treaded slick tires ($7.96 at present) after
reaching a thousand miles on the Fury and see if it picks up
its heels with new footwear.
Carl Fogel
Hugh Fenton
<carl...@comcast.net> wrote in message
news:itgsl0l9tvvr02c25...@4ax.com...
Oh the shame - WalMart classifies the bike as a TOY! But perhaps that means
you're allowed to have fun on it!
Hugh Fenton