Author Topic: how wide should the wheels be?  (Read 9780 times)

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Offline Jonny Hotnuts

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Re: how wide should the wheels be?
« Reply #15 on: October 05, 2007, 05:25:32 PM »
I agree that my car weighs more than the NT2 (a good deal less than 2600) but how does the salt know the different between two tires of the same size made of different materials providing the weight is the same.
Would the car somehow have more of a tendency to sink and create impressions (ruts) just because you used a harder material? I can see how an aluminum wheel may not seer as well as a rubber but I dont understand how, providing the edge has a decent profile it would cause more damage than a standard tire.


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"Sometimes it is impossible to deal with her, but most of the time she is very sweet, and if you caress her properly she will sing beautifully."
*Andres Segovia
(when Im not working on the car, I am ususally playing classical guitar)

Offline Unkl Ian

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Re: how wide should the wheels be?
« Reply #16 on: October 05, 2007, 05:58:08 PM »
A pneumatic tire deflects under load,increasing the size of the contact patch.

A solid wheel won't.

--------

You'll also find that larger diameter tires give a larger contact patch,
compared to a smaller diameter tire of the same width.
I guess the answer is "a Secret" .

Offline Dean Los Angeles

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Re: how wide should the wheels be?
« Reply #17 on: October 05, 2007, 06:01:00 PM »
Wearing tennis shoes? Stand up. Pivot on the shoe. Not a lot, just enough to move it a tiny bit. Notice the squirm underneath as the rubber hangs on. Aluminum has zero compliance. If you look at a loaded, accelerating, turning tire you will see side wall distortion and tread distortion. That's the advantage. Aluminum doesn't do any of that, and when the salt is perfect you still have a marginal grip.



I saw Andrés Segovia perform in 1984. 90 something and still spectacular.
Well, it used to be Los Angeles . . . 50 miles north of Fresno now.
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It's bigger than life or death! It's RACING.

Offline JackD

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Re: how wide should the wheels be?
« Reply #18 on: October 05, 2007, 06:08:39 PM »
One or the other must yield to have a usable contact patch.
One design will leave smaller yield mark than the other and restore it's shape within it's design capabilities.
The other will cause the racing surface to yield if it is to have any contact patch and the mark will remain.
Steering Geometry does not have to tip the wheel in a turn as has been demonstrated with a of a lot of east of New York Drag Bikes and at least 1 Bonneville entry.  :wink:
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Offline John Burk

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Re: how wide should the wheels be?
« Reply #19 on: October 05, 2007, 06:16:36 PM »
It takes very little deflection to reduce the unit pressure . If a 24" tire only compresses .010" the contact patch is 1" long .

Offline JackD

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Re: how wide should the wheels be?
« Reply #20 on: October 05, 2007, 06:59:40 PM »
How many remember the first time the Chet Herbert liner tried to run with solid aluminum wheels ?
When Vesco let the clutch out on the 4 motors, the wheels turned but it failed to proceed.
When it did finally move it only went a short ways before he turned out because the vibration back from the salt was so bad he couldn't see.
"I would rather lose going fast enough to win than win going slow enough to lose."
"That horrible smell is dirty feet being held to the fire"

Offline Harold Bettes

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Re: how wide should the wheels be?
« Reply #21 on: October 06, 2007, 12:34:22 AM »
Howdy All, :-D
 
Thanks to folks for the reports from the salt. Without them this place would be like the dark side of the moon.  :|

Relative to the "tire patch" issue: It is very easy to find out what you are dealing with by using something so simple as some paper and some carbon paper. 1) Jack up the vehicle and place plain white paper down on the floor under the tire. 2) Place carbon paper on top of the paper (carbon-ink side down). 3) Place another plain piece of white paper on top of the carbon paper sandwich. 4) Lower the vehicle on top of the carbon paper sandwich. 5) After imprinting the lower paper, again raise the vehicle and you can remove the carbon paper sandwich. The shadow of the carbon imprint is the tire patch. Although it is static and not dynamic, one can repeat the test with various conditions of inflation pressure and static weight and make an assessment of what the tire is doing by looking at the "tire patch".

This simple method is also very effective for checking conditions of "scrub" as well.

And next time we'll discuss cutting out paper dolls and sharing with others! LOL

Regards to All,
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If it was easy, everybody would be doing it.

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Offline JackD

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Re: how wide should the wheels be?
« Reply #22 on: October 06, 2007, 12:53:48 AM »
In the absence of carbon paper that may be hard to find, you can wet roll it now before the water is all gone also.  :wink:
"I would rather lose going fast enough to win than win going slow enough to lose."
"That horrible smell is dirty feet being held to the fire"

Offline Jonny Hotnuts

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Re: how wide should the wheels be?
« Reply #23 on: October 08, 2007, 10:46:44 PM »
I hated doing it but I have decided to take everyone’s advice and not use the aluminum spinners this year. Originally I did not want to have to compromise on the frontal design by having a 22+” tire at 130” (22" is almost the height of the bottom of the windshield). After some discussion (with our technical advisor ;) )on the wheels I have opted for and acquired the LSR proven 14” front tires made by Goodyear. This will let me build the front and still be able to swap to the spinners when the time is right, and have a backup if there is any heat from tech. 
jonny_hotnuts@hotmail.com

"Sometimes it is impossible to deal with her, but most of the time she is very sweet, and if you caress her properly she will sing beautifully."
*Andres Segovia
(when Im not working on the car, I am ususally playing classical guitar)