Date:         Fri, 16 Apr 1999 09:43:49 -0700
Reply-To:     Davidson <wdavidson@THEGRID.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Davidson <wdavidson@THEGRID.NET>
Subject:      Re: Syncro tire dia. spec. - tolerances?
Comments: To: "Fitz-Randolph, Douglas" <dfrandolph@TALKAM.NET>
Content-Type: multipart/alternative;

The measurement you want to compare is NOT the tread... it's the circumference of the tire near the center (diameter is too hard to measure).... Measure by wrapping a string around the outside of the tire, mark the spot on the string where it meets itself.... then see if that's the same spot for the other tires... or how far off it is....
Bill
90 Westy Syncro
    -----Original Message-----
    From: Fitz-Randolph, Douglas <dfrandolph@TALKAM.NET>
    To: vanagon@GERRY.VANAGON.COM <vanagon@GERRY.VANAGON.COM>
    Date: Friday, April 16, 1999 9:31 AM
    Subject: Syncro tire dia. spec. - tolerances?
    
    
    Brent Christensen wrote: ...My understanding is that all tires for a Syncro need to be within 2.5 mm. 
    Is this the correct spec?... 

    I'd really curious if anybody knows this spec *for sure*. 

    The tires I've been running for about 800 mi. were purchased slightly used, with 2 of them having about 1-2mm less tread than the other 2. In retrospect, I probably shouldn't have bought them, but the difference seemed so small at the time... If it's going to end up messing up my drivetrain though, I'll replace them. 

    The manager of my local highly reputable tire shop said the difference - hardly noticeable -  wouldn't cause a problem - he seemed pretty knowledgeable about various awd systems (Subaru, Volvo, etc.) - and he certainly had an easy opportunity to sell me a new set of tires, didn't he?! The local VW dealer would only say "They all have to be the same size and treadwear" and didn't know anything about acceptable tolerances - not much help.

    I know all about the whole replacing all 4 (or 5) if one is bad thing, but how close do they really have to be? The 1-2 mm difference only translates into several rotations per mile - it seems as if turning while driving normally would account for almost that much rotational difference on its own. (Would you eventually ruin your VC if you drove the same direction around a racetrack for miles and miles? Probably not, but I'm not an expert. And assuming  500 laps at Daytona won't blow the VC, would it make sense to match the treadwear left to right rather than front to back? Hmmm...)

    Any VW Syncro engineers out there? 

    Doug Fitz-Randolph 
    Yarmouth, ME 
    dfrandolph@talkam.net 
    '90 Syncro 


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