>Ok, I have let me bother this long enough.  I have a '71 campmobile.
>The previous owner installed 185/75 passenger car tires.  At an
>indicated 72mph the bus travels at 56.  The speedo used to bounce
>until I lubed it.  Now it works smoothly throughout its range.  So, do
>I have the wrong size tires, a goofy speedo or both?  Mostly, I am
>interested in getting the proper size tire on there.  I want my engine
>turning the speed the factory intended.

That's the right size tire, according to my owners' manual. Of course,
even among "identical" sizes, tire diameter varies *slightly* from
manufacturer to manufacturer, but seldom more than 1% or so--
not enough to cause the kind of error you're seeing.

You've got a weird speedo. Maybe it was once rebuilt wrong, or maybe
some PO put giant tires on the bus and adjusted the speedo to match?
(are they even adjustable, other than by changing the internal gears?)

My $.02...

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 Steve Maher   smaher@gi.com       '80 V6anagon w/Chevy 2800
                                   '66 Mustang Coupevertible, for sale

 Check out the cars at http://www.lookup.com/homepages/76242/home.html

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