Britbike forum Forums Thread Like Summary - K70 cracked capers

took the 72 T120 out today for a ride in cool morning air got home and decided to spiff it up as i was cleaning tires i noticed numerous sidewall cracks on from 3.25x19 K70 this tire is not that old and has tons of tread left the one that was on the front before did the same thing any of you'uns had K70 sidewall crack capers? PS going to try different brand ...soon...

What’s the manufacture date?

I have a set of K70s here. Never been mounted. “Look” like new but are actually 15+ years old. IMO the only thing they are good for now is a static display.

I learned the hard way that the LAST thing you want to
purchase for a project are the tires……and then only once the bike is ready for the road.

G

I just looked, and the K70 in my shop is dated 2913. Looks good, but I wouldn't use it.
Probably about as effective as the conical-brake wheel from which I removed it.

I hate threads like this..... got me looking at the tires on my A10, which does not see as much use as it used to. The front is an Avon ribbed from 2008 and the rear is a Kenda from 2010. Seems like I put them on just a few years ago.

That's so you can claim the bike is, "All original, even the tires."

As rubber deteriorates and ages, it becomes harder and cracks, hence the appearance of cracks in the side wall.

I wouldn't try riding with tires in this condition as the grip will be seriously compromised and might lead to an accident.

If your riding is mostly on road, get a set of Avon Road riders as Allen suggests, these tires have a modern rubber compound with excellent grip, I use them on my Commando and A65 and they are great.

Not sure how the K70s compare to the Road Riders, maybe others can chime in.

A couple of years ago, I started my a65 up after the winter and took the long way to breakfast. A lot of twisty bits and sweepers. Bike felt like I was riding on ice and snow. Looked for oil on the tire, but there was none. Plenty of tread and no sidewall cracking. Then a light bulb went off. The tires were 12 years old and hard as rocks! Checked my Trident and my Norton. Tires ranged from 12-15 years old. Changed them all. Huge difference. Didn't bother with the smaller bikes. Don't notice as much of a difference as long as its dry out.

Ed from NJ

I used to drag race my 67 650 and later a 73 Trident..The bikes took the punishment in stride...Nothing broke...You had to spin he rear tire or slip the clutch to avoid a wheelstand..

The Avon is pretty much gone anyway Gordon, and I will put 2 new Avon Road Riders on soon(?) As far as worn TSMR tires, I kinda remember a certain Thunderwing pilot running it with cord showing on the rear....and he don't exactly baby the throttle

lol

i am just now looking at a brand spanking new pair of avon road . . .runners

sitting in my shop in the dark since i got em . bought for my 72 T120 and things got in the way . . .





dunno what to do with them now

well i will proily git jumped on but.....my reading has indicated that K70 was never designed to go on front rib tire was what went on home market Triumphs etc. and K70 was marketing ploy for US market to give racier look scalloping comes from tread blocks squishing under steering /braking the K70s i have used on front of my 72 T120 scallop badly after just a couple thousand miles

well, the reason those tires are still brand new after 23 years is that i wont put em on a bike. rubber has all sorts of volatile compounds that outgas over time. kept awsy from sunlight i am under the impression that a tire will be good for quite a while. but like allan says, tires are all that keep the motorcucle upright.

so good or not, i probably wont use them on a machine

i am going with Duro HF317 on front of my 72 T120 and wont ride it again til i get the scalloped and cracked K70 gone i have one of the Duros on front of my 68 A65 with K70 on back and it works very well