Coker Tires?

[OldHog66]

Coker makes a tire that is a replica of the original Goodyear used in the '60's.

While it is the closest in "looks" to the original tires, someone told me that they are more of a flat surface on the bottom with a bit of a ridge on the side, making straight tracking great but iffy on some corners.

This is a restoration, (will be tube tires, whitewall) but I also don't want to fall on my ass!..

Recommendations? experience?



Thanks,
OldHog66
Steve

[Ohio-Rider]

Steve, There are folks who swear that Cokers are terrible tires and many others who ride on them daily. I have a set of them on my panhead and for my style of riding with that bike they seem fine to me. I will tell you that if I where going to be doing alot of inter-state riding, then I would change to a differant brand right away. The Coker's just don't give me that happy feeling I like at 70mph. Of course thats just me.

[PRG]

Howdy Steve,

10-4 on the previous comment regarding interstate use/predictability. I've used their 4.50 x 18 diamond treads on a 440 for 15 years, and as one aspect of them is a rather soft compliant compound and machines of this era favored heavy rear brake bias, I gladly forgo long wear for better braking as rears have lasted as little as 4000 miles on this machine. Plus, they are convenient and relatively cheap as Coker is located at the other end of our state.

The irony is that any close replica of a period tire of that era is going to have a zone in its cross section where there is a notable (unnerving) transition from the primary tread face over to employing elements of the outer tread or sidewall when cornering. This is a huge problem with Avon Mk II rear tires on Vincents as they are hard and unyielding. Fortunately with Cokers, they are soft enough to cushion this transition some. A good example of one which does not is anyone still using the - much loved in my case - 17lb Indian zig zag tires made in Taiwan back in the early 80's as you can see an NOS set on my 441 here. In that lighting, you can see the almost perpendicular transition to the sidewall.

One thing you'll notice with any modern tire is that it maintains a uniform radius dimension in cross section farther out from tread center than any vintage zig zag and some such. A good example, and I tire I've used over 20 years on a crusty old shovel for vintage appearance, yet a semblance of modern performance is the Continental K112.

[portagepan]

I don't know. All I can say is, that the 1965 Harley FLH I ride, had handling problems with the Cokers on. I put on the new Dunlops, with the thin WW, and it handles a whole lot better. There has been a lot of input on this before. I am not trying to knock the Cokers, but my life is more important than repop tires that "look original". I think the later, heavier Pans, and the Shovels are more prone to handling problems than the lighter hardtails were. I have a '72 Shovel that is really picky about tires. I put on a slightly oversize rear one, and developed a wobble from 75 mph on up. Scary. Went back to stock, no problem. It was just the half ass Harley suspension, that wouldn't handle the extra push from the more agressive tread of the newer Dunlops.
Mike

[PRG]

Howdy Mike,

Agree with you there. Shovel I referred to is a 77 FLH here fully loaded with trinkets that felt unnervingly darty at highway speed on the pair of nos double thin line white wall Good Years I fitted. Thought if I could kick the fork trail out just a little, it might be more stable so lowered the rear suspension as much as possible, as you can see. No go, peeled those off and fitted K112's 21 years ago and all has been better since.

They are a good compromise, more uniform contact patch across the face, vintage look but not so much stick like a modern vintage-look Avon that the suspension is (more) overwhelmed ....for whatever that might be worth on mild mannered old dresser.

No mild tank slapper's now, just onset of a lazy weave in fast bends when pressing the issue a might (accompanied by a comet's tail shower of sparks to entertain those behind you).