Coker-Goodrich Silvertown Radials

  • Thread starter Larry & Nancy Solheim
  • Start date

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Larry & Nancy Solheim

Just received my new P185/80R13 radials, but have discovered that the wide white
sidewalls are 2-7/8" wide rather than the 2-1/4" width per the tire spec and
Amphicar standard. When called, the customer service folks at Coker seemed
surpirsed and confused. I figure if I'm going to have the wrong tire, I might
as well have the $30.00 readily available blackwall as this nearly $150.00 (w/
freight) tire.

I thought the nearly 3" white sidewall looked EXCEPTIONALLY large on the 13"
tire. From those of you buying these in the past, have the whites always been
oversized? I suspect this is a new batch that was incorrectly made and they
maybe hoping to sell them. Almost impossible to believe that no one knew about

I'm a bit nervous about the tracking issues recently posted about radials.
Since 1993 I' ve put over 45,000 miles on the bias belted Coker Classics
(driving and flat towing); the car tracks great (except for the bias belt
practice of following road defects), but I'm hard pressed to get 25,000 miles on
a set. I was hoping the radial sidewalls would put less load on the suspension
by absorbing some road imperfections and the overall wear would improve.


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Active Member

As you might know, I run P185/80R13 radials on my hopped up Amphicars and they track perfectly all the way to almost 90 MPH. If people get the front tire pressures low enough (I run about 20-21lb) to compensate for the fact that there is no weight up there, the cars track just fine at any speed.

Obviously wide white wall width is a matter of taste but I too think one can go too far with the white side wall look. 2 1/4" seems as wide as I'd like and I would rather error for too narrow than too wide. I bought 10 tires some time ago when it seemed that nobody could come up with a 13" radials except a Korean tire company. They have a 3/4" white wall width and on a red car with white wheels that's enough white for me. I think they make the car look a bit sportier too.

I'm not sure though about what they would look like on my white car with it's red wheels. The car doesn't need tires now and I might be willing to sell the last 5 new tires that I have. They are still in their boxes.

John Friese
67 White
67 Red


Active Member

I once bought a set of those Silvertown radials and found that they absolutely wouldn't fit the car. I learned at the time that the widest point width of the tire varies quite a bit from model to model and those Silvertowns were crazy wide and would barely allow any clearance on the rear of the car. I had special ordered them and returned them a quite a loss. An expensive lesson learned. When Firestone made that size, they fit easily in the Amphicar. The Korean Maxxis tires I have fit fine at the rear but I used a 1/8" spacer at the front to prevent rubbing when the wheels were turned to the stops.

If anyone buys those extra new tires that I have, I'll include a couple of spare 1/8" spacers in case you need them.

John Friese
67 White
67 Red


Jon & John:
First, please note that original post Jon used to reply to was from 13 years ago (2004), when I had the car only 10 years & was making the initial transition from bias to radial tires. If I recall, Coker took them back on their dime, issued a full refund and I ended up using the 185-80r13 Diamondback radial 2-1/4" WSW re-strikes (w/ rear spacers) from then until the present, although w/ that size now obsolete I am not sure what I will do for the next set. Since their WSWs were re-molds, the "host" tire varied from production lot-to-lot. I do like the 2-1/4 WSW look and may have to spring for the Universal 175-80 tires next time out.

Flat towing (compounded by a slight toe-in issuethat was corrected) was the ultimate cause for the outside front tire wear. Although my setup is as flat as possible, being dragged behind the RV changes the suspension loading forcing even less weight on the front tires. At the time of that post we had 45K miles towing, subsequently we have over 95K miles and it remains an issue (except I am trailering now -- the car becoming too valuable for the flat-tow exposure).

As John pointed out, the radials completely solved the bias belt tracking issue, where the bias tires wanted tonfollow every road crack & groove. Grated bridge decks were always an exciting challenge!


Active Member
Jon & Larry,

A number of years ago I was using Diamondback 185-80r13 wide white walls too and the base tire they were using at the time were Firestones but when I went to buy new tires a few years ago Diamondback couldn't find a base tire to work with. At that time I found the Maxxis tires, checked out their reputation and bought 10 of them, thinking they may go away too. I told Diamondback about those tires but they didn't seem bothered enough to look into getting them for a base tire. The Maxxis tires are an all weather tread, which makes them good for pulling out on a moss covered ramp. I had some trouble once with highway tread in such a circumstance.

I talked to Diamondback about sending these tires in to convert to wide white wall but the shipping expense just made that impossible.

John Friese
67 White
67 Red