[Land-speed] A Protocol Question...

[Dave Dahlgren]

It started with measuring the loaded radius or unloaded to get the proper 
circumference..
My point is the whole tire has to go one rev and all of needs to touch the 
ground so loaded or unloaded makes no difference..
And yes tires can and do grow but at 200 to 300 starting with 90 psi I doubt 
very little..
My speed vs. rpm data suggests the goodyears grow very little due to rpm of 
the tire.
And the growth is not being covered by slip as both the fronts and rears are 
motored..
----- Original Message ----- 
From: "drmayf" <drmayf at mayfco.com>
To: "Dave Dahlgren" <ddahlgren at snet.net>
Cc: <rgg14 at cox.net>; "Elon" <saltfever at comcast.net>; "'land-speed submit'" 
<land-speed at autox.team.net>
Sent: Saturday, April 26, 2008 11:33 AM
Subject: Re: [Land-speed] A Protocol Question...


>I lost track of what is trying to be proved here?  Rolling radius is real. 
>That is the distance between the axle centerline and the road surface. That 
>distance is what determines the tractive force at the surface.   A deflated 
>tire will have to make more revolutions to go the same distance as one that 
>is inflated. It is kinda like an orbit. Speeds and velocities change on the 
>rim with radius to the orbit path.  Look at a tank's tread...many radii at 
>all kinds of points on it.
>
> What was being proved ot talked abotu here, lol..
>
> mayf
> Dave Dahlgren wrote:
>
>>It was a bit of an analogy.. Take a fan belt and put a mark on it. Then 
>>put it
>>on a bench on edge like it is a tire and put a mark on the bench that 
>>lines up
>>with the one on the belt.roll it one revolution and mark out how far it 
>>goes.
>>A typical roll out test like you use with a tire to check the 
>>circumference.
>>Now change the foot print that is contacting the bench and do another roll 
>>out
>>test.. Try to make the distance traveled in one revolution change..PS hope 
>>you
>>have a lot of time if you think it will change..
>>Dave
>>  ----- Original Message -----
>>  From: rgg14 at cox.net
>>  To: Dave Dahlgren ; Elon ; 'land-speed submit'
>>  Sent: Saturday, April 26, 2008 10:41 AM
>>  Subject: Re: [Land-speed] A Protocol Question...
>>
>>
>>  Dave
>>
>>  OK, I'll bite. What is the fan belt test????