Tire advice -- ok to drive on bias plys?

[Paul S.]

Hi all,

It's time for some new tires for my '69 convertible. I am planning to have the car judged for the first time this summer, so to that end, I was thinking of getting some of the reproduction bias ply tires from Coker or Kelsey.

My question is, are they good enough/safe enough to drive around on, or am I going to have to buy a second set of radials as well? I only really take the car out for shows and "Sunday drives", but I don't have any experience driving on bias ply tires, so I am looking for opinions of folks who do...


Thanks,
Paul

[Terry M.]

Re: Tire advice -- ok to drive on bias plys?

Hi all,

It's time for some new tires for my '69 convertible. I am planning to have the car judged for the first time this summer, so to that end, I was thinking of getting some of the reproduction bias ply tires from Coker or Kelsey.

My question is, are they good enough/safe enough to drive around on, or am I going to have to buy a second set of radials as well? I only really take the car out for shows and "Sunday drives", but I don't have any experience driving on bias ply tires, so I am looking for opinions of folks who do...


Thanks,
Paul

Paul
Kelsey will judge the best.

There is no safety problem as these are new tires, not 50 years old. If you only drive as you describe there will be no driving or handling issues. Bias ply tires will not feel the same as radials, and they will flat spot. They will be a little bumpy when you first start driving after winter storage, but after 5 miles or so they will be fine.

Whichever tire you decide to get be sure to have them Road Force balanced. Use Google to find a shop near you that uses a Hunter Road Force balancer.

[Don H.]

Re: Tire advice -- ok to drive on bias plys?

I feel they are unsafe to drive very much at all when you are used to radials. Years ago I was driving to a Regional and put a spare set of correct bias plys on my 1965. I happened on a stretch of old blacktop that had the top layer taken off (before the new layer is installed), leaving a small grooved surface. It felt like I was driving on ice! It is also a problem when you go over some seams in the road, radials "float" over the seam but bias plys jerk. My humble opinion, Don H.

[Rich G.]

[Deane M.]

Re: Tire advice -- ok to drive on bias plys?

FWIW, I put a set of new Kelsey bias plys on my 70 L46 cpe in 2010. Drove it from Mass. to No. Carolina (900 miles each way) for the National. Car achieved Top Flight. Drove it home. Tires performed well. Little bit of a challenge coming back through Hartford Ct. in the rain (yikes). Drove the car for a while with those tires. As Terry said, they do flat spot but other than that they were always ok.

[Bill M.]

Re: Tire advice -- ok to drive on bias plys?

Paul

I have bias ply's on my 65 for the last 15 years and I have radials on my 67 for 32 years. the two cars drive as different as night and day. The 65 floats all over the place on the bias ply's especially on rough or seamed roads. You really have to pay more attention to the road surface. When this set is worn I will go to radials. hope this helps. Also I have never had the 65 judged.

[Jim L.]

Re: Tire advice -- ok to drive on bias plys?

Three more data points regarding bias ply tires:

1. When I moved to the left coast from the right coast, I drove my bias-ply-tired '60 to get it out here. There was no issue with the tires until I got to CA, where some roads are grooved. The bias ply tires tended to want to follow the grooves.

2. For the same reason, I also drove my '57 to the left coast and it, too, was on bias ply tires, these being reproductions. No problems what so ever and for this trip, I was in rain for 2/3 of the trip.

3. My Grand Sport vintage racer is required by the rules to race on bias ply tires. I love'em. Seriously. Super sticky as all racing tires are, at the limits of adhesion, they give plenty of warning before they let go. And when they do let go, it happens gradually. In talking to guys who have raced on radials, I've heard than when they let go, you are gone; there is little opportunity to catch the car.

My bottom line is that driving on bias ply tires isn't the nightmare some would have you believe. And remember, when these cars were new, they came rolling on bias ply tires.

Jim

[Joseph L.]

Re: Tire advice -- ok to drive on bias plys?

I bought a new set of Silvertowns for my '57, drove it 450 miles to the Lake Tahoe Regional and back, mostly on the 395. That was the best drive I have had. Two fingers on the wheel and straight down the road.
Joe

[Kenneth B.]

Re: Tire advice -- ok to drive on bias plys?

We drove on bias ply tires for years befor radials came along. They were fine then & the new repos are fine now. the cars in the 60'S were very fast & I had the 1963 427 Ford over 100 MPH many times with no problem. You do have to steer the care more as the bias tires want to move with every crack in the road.

[Jimmy G.]

Re: Tire advice -- ok to drive on bias plys?

Yes you can ---- But why would you.

Radials are so much better

[Joe L.]

Re: Tire advice -- ok to drive on bias plys?

Hi all,

It's time for some new tires for my '69 convertible. I am planning to have the car judged for the first time this summer, so to that end, I was thinking of getting some of the reproduction bias ply tires from Coker or Kelsey.

My question is, are they good enough/safe enough to drive around on, or am I going to have to buy a second set of radials as well? I only really take the car out for shows and "Sunday drives", but I don't have any experience driving on bias ply tires, so I am looking for opinions of folks who do...


Thanks,
Paul

Paul-------


People drove on bias ply tires for many years. I used them on my original owner 1969 Corvette for at least 15 years without any sort of problems. If this could be done then, it could be done now.

One more thing: the absolute best handling tires I ever had on my Corvette were sets of bias ply, Goodyear Polyglas GT size F-60-15. They handled much better than any radial tire I've had on the car since. I switched to radials when Goodyear discontinued the Polyglas GT's. The Polyglas GT's were very hard riding but excellent handling.

By the way, Kelsey now offers the Polyglas GT's in reproduction. Of course, they're not correct for any Corvette but they do handle!

[Paul S.]

Re: Tire advice -- ok to drive on bias plys?

Thanks very much to everyone for the replies. I've decided to purchase some reproduction bias ply tires and try them out. I'll use them for judging, and if I don't like the way they drive, I can always buy a second set of radial tires later.

So now, a new question... which reproduction tires will judge the best? I have heard that the Goodyears offered by Kelsey are better than the Firestones offered by Coker. Is this true? If so, why?

Also, I heard someone say that one of these companies will make the tires "more correct" by special request. I believe it had something to do with using a date stamp that was shorter in length like it would have been originally. Anyone know anything about that?

Thanks all,
Paul

[Joe L.]

Re: Tire advice -- ok to drive on bias plys?

Thanks very much to everyone for the replies. I've decided to purchase some reproduction bias ply tires and try them out. I'll use them for judging, and if I don't like the way they drive, I can always buy a second set of radial tires later.

So now, a new question... which reproduction tires will judge the best? I have heard that the Goodyears offered by Kelsey are better than the Firestones offered by Coker. Is this true? If so, why?

Also, I heard someone say that one of these companies will make the tires "more correct" by special request. I believe it had something to do with using a date stamp that was shorter in length like it would have been originally. Anyone know anything about that?

Thanks all,
Paul

Paul------


The Coker tires are Firestone reproductions. They are a fiberglass belted tire and were used on other cars of the period but not Corvettes. They are SIMILAR to the original Corvette Firestone tires but are easily discerned. Among other differences they have a different tread rib count than the Corvette tires.

I and others believe that the Kelsey Goodyear reproductions of the Speedway Wide Tread are the most authentic reproductions for 68-72 Corvettes available today.

I know nothing regarding your last question.

[Elliott P.]

serchinclassic looking

[Dennis C.]

Re: Tire advice -- ok to drive on bias plys?

Don't expect to do any better in judging. Tires are a standard deduct item and point deduction should be the same wherever you go. I don't have the standard deduct chart with me, but if I remember correctly the deduct will be 60% of available points.

The standard deduct charts are rediily available at some judging schools and the NCRS store.