it's not the speedo likely.
it's the cable.
operating through a curve ..
and wear occurring during the last 20 years ..
the cable, if at all sticky, will tend to jump while it turns ..
like bind-jump-bind some more, jump etc.

what I do is jack up the LF tire .
dribble very high quality synthetic spray lube into the top of the speedo
cable while turning the LF wheel with my foot.
that works..
or you could have a terminally tired speedo cable ..
but so far I have always fixed them this way.

Scott
www.turbovans.com
----- Original Message -----
From: "Don Hanson" <dhanson928@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, November 23, 2010 7:21 AM
Subject: Speedo noise, cold day....

>  On cold mornings my 84's speedo goes "Skritch..Skritch...sckritch...whirr
> whirr whirr whirr" for about 10 miles when I first start out.  Mine has
> the
> snap-in cable attachment and I have lubed it with some SA Besto 2000 a
> couple of times, both down the cable and with a small vacuum line attached
> to my spray can, into the speedo housing where the cable snaps in..
> That seems to help a little but the sound still occurs, sometimes in a
> week,
> sometimes right away..The instrument needle oscillates in time with this
> sound...moving maybe a couple of MPH back and forth around the indicated
> speed.  I think the whirring gets a little louder as the speed increases.
> This only happens when the temp is below or near about 35f...and it seems
> to
> go away or fade into the backround after the van warms up...inside?..On  a
> temperate day, or after it warms up,  the speedo behaves correctly...quiet
> and steady at the needle...
>   I've swapped in a different speedo, perhaps about 3mos ago...the other
> one had the Vanagon  'no-go-odo'
>
>  So how do I trouble shoot this to see where the noise is coming from?
> Cable? Connection? Speedo itself?  Anyone have any tips?  Thanks in
> advance,
>
>  Don Hanson