Post #43,236
6/23/02 11:03:20 AM
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Order now... for Guaranteed increasing of your...
Tire hardness...
Bwahahaha...
Karsten just make sure your tire are that thier maximum hardness... (assuming you are using Street tires here for your trike, and not "knobbies")
Reasoning, I have a friend that is a very good Mathematician, and he was doing very well bicycling around, also. HE also keeps his bike in very good shape... nominal everything eveyrthing exactly in the middle of specs...blah blah blah...
Well, one day crusing down a slight 7.5 mile hill... he was at ~45 for 5 minutes and the front disentegrated on him... No problem... he carries an extra emergency "fold-up" tire and tube in his fixit pack on the bike... while fixing the front he just checked the rear... it was leaking badly also... chunks out of the sidewalls and such. But slow enough he could get to the next "tire" shop (bike shop that is) and get two tires and tubes.
Owner of the shop asked him if he was coming down the hill when he had a problem... Owner said max pressure is the place you wanna be. Even about 10% over the max is better.
Dave has never had a problem since going down that hill. Uses the same brand tires and tubes.
Just an FYI.
greg, curley95@attbi.com -- REMEMBER ED CURRY!!!
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Post #43,241
6/23/02 12:55:34 PM
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I keep mine hard all the time
...actually, checked pressure and added air front and rear before heading out on this ride. Tires are 1.25" front and 1.50" rear, slicks (no tread), rated to 85psi. I keep them at 100 psi.
The bike itself is a mountain bike, but rigged for commute / touring. Slicks, Scott bars, modified stem & seat post, and a good lighting system.
For mountain biking (for real, off-road, which isn't where I'm usually at these days), before hitting the dirt, you'll drop pressure to 20 lb (most nobbies are rated to 45), and before the downhill, you'd drop the seat hight. This improves both balance (lowered center of gravity) and back-end abuse, if you get my drift. Incidentally, this is why Mt. Bikes have quick-release seat post fastners, though most people don't seem to get this....
I did lower my seat about an inch before hitting the Oakville Grade, both for balance (there are a couple of turns on the way down) and to lower my profile -> less wind resistance. Seems to have helped.
I love that ride....
--
Karsten M. Self [link|mailto:kmself@ix.netcom.com|kmself@ix.netcom.com]
[link|http://kmself.home.netcom.com/|[link|http://kmself.home.netcom.com/|http://kmself.home.netcom.com/]]
What part of "gestalt" don't you understand?
Keep software free. Oppose the CBDTPA. Kill S.2048 dead.
[link|http://www.eff.org/alerts/20020322_eff_cbdtpa_alert.html|[link|http://www.eff.org/alerts/20020322_eff_cbdtpa_alert.html|http://www.eff.org/...a_alert.html]]
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Post #43,246
6/23/02 3:32:20 PM
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When I think of the actual 'tire patch contact area'
on these flimsy contrivances - and simple physics...
I deem 55 mph on one of those dinky minimalist "tires" (tyres) - akin to 130 mph down The Grapevine (er, the SoCal one outta LA, that is) on a proper motorcycle. Only worse.. when you consider the huge tire dia. and flexibility of Everything. And that dinky patch.
Well.. it's gotta be a good forced Attention akin to meditation to keep the sucker properly under you. No daydreaming, y'hear?
As to dirt - yes quite: you say that some don't get it about lowering the seat? A good primer for illustrating that is: English Trials, usually on single-cylinder machines with Lots of v.low speed torque, smoothly applied with the skill of a dancer.
But on a m/cycle - the pegs you stand on (to lower your CG as much as possible, natch) aren't moving!. You Never "sit on the seat", at any height, for same obvious reason. Are you saying that bike riders do Not (well, try to) stand on the pedals ??
If they 'sit' - sounds like lots of fall-offs. Hmmm I see a tech mod needed: a switch on handlebar + a solenoid which locks the pedal crank solidly, allowing use of body weight on the feet - to exert proper English as Newton intended. (Obviously you can't do this Up-hill. D'Oh)
(Ugh - a bizness opportunity)
Ashton Da Vinci
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Post #43,254
6/23/02 4:48:52 PM
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Staying on top
Um...no problems here.
You're familiar with the road (and if you're not, become one with it...in the metaphysical sense only). It's 1.5 miles dropping 800 feet with four swooping turns as you drop into the valley.
Physics tends to say that objects moving in straight lines tend to stay that way. Worst problem I've had on on a bike is shimmey, usually caused by poorly distributed weight. On Oakville, the issues are ratty pavement (it's pretty good in general, though there's a couple of rough spots), oncoming traffic, wildlife, and your hardware flying apart on you. Plenty to focus on at that speed, but keeping the bike upright really isn't the issue. More than enough angular momentum to see to that.
As for for standing in the pedals, amazingly enough, my weight distributes pretty evenly across the pedals. No need for a lock-out. And if I need motive power, all I've got to do is start spinning.
--
Karsten M. Self [link|mailto:kmself@ix.netcom.com|kmself@ix.netcom.com]
[link|http://kmself.home.netcom.com/|[link|http://kmself.home.netcom.com/|http://kmself.home.netcom.com/]]
What part of "gestalt" don't you understand?
Keep software free. Oppose the CBDTPA. Kill S.2048 dead.
[link|http://www.eff.org/alerts/20020322_eff_cbdtpa_alert.html|[link|http://www.eff.org/alerts/20020322_eff_cbdtpa_alert.html|http://www.eff.org/...a_alert.html]]
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Post #43,311
6/24/02 11:26:20 AM
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Here's a video for you of some trials action
Go [link|http://www.gasgas.com|here] and click on one of the video links at the top left. Some of the things these guys do don't look possible. (Real or WMP only, sorry.)
===
Microsoft offers them the one thing most business people will pay any price for - the ability to say "we had no choice - everyone's doing it that way." -- [link|http://z.iwethey.org/forums/render/content/show?contentid=38978|Andrew Grygus]
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Post #43,346
6/24/02 4:40:19 PM
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Thanks!___Great site
..and captures the flavor of the Impossibility - for us mere mortals.
Think the flic is more like ~ Int'l Grade Moto-Cross meets Skateboarders with a Death Wish though. Motocross in past has been likened to aviation*: typically people ricochet around a course at humongous speeds.. merely touching 'ground' long enough to alter airborne direction! (to miss an obstacle or 'use' it for launch). Virtually all of the Masters got their first micro-bike at about 2 years of age (some have guessed: One year, but..) and rarely got off them except maybe to eat, occasionally sleep. (They Know No Fear because they got so good so fast - rarely experienced the Second Law: Pain Hurts.)
* worse: you are Right At The Scene of the Accident 100% of the time, not 5000' ft. of thinking-time away.
English Trials OTOH are mostly s l o w; feet must Never come off the pegs [Rule 1]. The course has been prepared by someone with the combined skills of Torquemada and Idi Amin and the conscience of a sleazy biznessman whose name begins with a G or a B:
Greasy.. Slickern'shit MUD or mossy or mud-covered Rocks - as many reverse-camber "turns into wall-like obstructions" as possible. Dead stop is an often event, as various tactics are tried. Getting over decaying logs with a coefficient of friction of 0.001 is merely: usual. Get the pic? Ballet in slo-mo.
Dick Mann, a (Pro) racer and all-round Master of all things kinetic.. used to come around to the "playground" of moderate hills & such at Point Richmond (Calif.). Sometimes he'd ride up, kill engine, carry on a conversation of 10 minutes or more -- all the while with feet on pegs, and remaining stationary! Then.. he'd kickstart (no namby-pamby Electric stuff on lean, mean machines) and ride off [or ^^Up^^].
A perfect illustration of the limits of brute-force, bravado - it's more like ballet than 'combat', and apparently for actual Pros, it's chess and not jousting.
Loved the concrete cube! Now slather it with Slik-50.. :-\ufffd
Ashton
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Post #43,298
6/24/02 10:13:58 AM
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Careful on that, though...
When the pavement gets warm enough, it has a tendency to heat up your tires. Which heats up the air in your tubes. Which causes the pressure in the tubes to rise. Which could cause a blow-out.
Happened to more than a few people on last year's AIDSRide, and the temp was only 75-85.
I just completed the Chicago-based MS 150 ride (Chicago to Kankakee to Chicago) this weekend. 162 miles. 100 degrees on Saturday, 103 on Sunday. I lost 7 pounds. Oh, and there were a few over-pressurization tire pops.
-YendorMike
What if the hokey pokey really is what it's all about?
- Jimmy Buffett, June 20, 2002, Tinley Park
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Post #43,313
6/24/02 12:13:21 PM
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Indeed. PV = nRT
A friend rode his old 10 speed to work one winter day - it was around 20 F. The bike was stored in an unheated garage. He pumped up the tires to the limit before leaving home.
Got to work, put his bike inside. His shop was rather warmer than usual - maybe 80 F.
A few minutes later he heard "POP!" and "POP!". He wasn't too happy. The rise in pressure due to the rise in temperature was enough to pop the tires.
Remember: PV = nRT - it's the law! :-)
Cheers,
Scott.
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Post #43,335
6/24/02 3:24:26 PM
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While an Important formula..
My two-wheel equilibrium Rulez have a Higher priority..
As with the well-known symbol for er Windoze Stability\ufffd:
-*-
{{\\______/}}
___\\____/
____\\__/
_____\\/____
//////////////
_*_ = a fly about to land
While that describes a 'point' problem of one dimension (much like the Manufacturer's mind$et) moving on to a plane/road, with only TWO wheels has a ~ flavor, so I think:
F= Gm1m2 / R2
[Along with the ever-popular F=ma + Peter Principles, natch]
..are the ones to remain in Awe of.
:-\ufffd
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