Period tires: Dunlop TT100 vs Avon Roadrunner

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Some remarkable mileage being quoted. I think we must have abrasive roads here in SE Briton.
That was the standard figure being quoted in the Yank M/c press for the rear Conti TK 17- which is why the despatch riders around London loved them-Don't ask me how I know!! Sadly, they appear to be no longer available.
 
Do tyres age through time, or work hardening?

I have always understood it to be time, meaning that even an unused old tyre will have gone from sticky rubber to something resembling Bakelight...

Time seems to do it. Time in the sun is particularly damaging for tires, but time indoors eventually gets them too.
It's good to check the date code on new tires. Sometimes bargain priced tires are truly a bargain, sometimes they have been sitting for years already.
I've been told that running in extremely hot temperatures can also harden a tire up to make it both slippery and long wearing. Perhaps the members from OZ or other hot climates will comment.

Glen
 
I have heard that ozone ages tires. So keep your tires out of the upper atmosphere. Really, keep them away from electric motors.
 
No use changing midstream. Go for what you decided. The Contis might be excellent, but.......
 
For canyons, I run a non-DOT AHRMA Avon AM26 (IIRC) on WM-3 19 up front and a Roadrider on WM-3 18 rear; front wheel when riding hard is the Rock of Gibraltar. Mileage? The front gets hard/heat cycled before it wears out. Rear mileage? I run lower pressures than most do at both ends, especially when the day's ride will be in the canyons and that heats 'em up and wears 'em out, especially the rear. Less than 3000 out of rear but that means that the tire lasts at least a year. I can afford a $90 tire (or less) once a year; especially when I can show the late model crowd what an old Commando can do.
 
What tyre pressure do you use and how much do you weigh?
 
It always depends on conditions, day’s temps, road (bumpy or smooth) but usually 30 front 27 rear as starting point for my Norton’s canyon rides and those pressures are a starting point for higher speed national forest type of roads or when there will be twenty or so miles of freeway to get to the’ canyons that we will be riding.

Locally, there’s a tight slower average speed canyon where I’ll go to 28 and 25 if I’ll be meeting my more competitive friends.

Lower pressures offer sevaeral advantages - quick warm up, more stickiness when warm at lower speeds, and a poor man’s Ohlins of a more compliant carcass that absorbs bumps better taking some of the load off of the suspension. You also get a slightly larger tire footprint that better shapes itself the road surface

Downsides are instability as speeds rise, greasy feel if your speeds are higher than anticipated, and a much higher rate of tire wear.

Some tires respond to lower pressures better than others likely because of construction differences. Lower pressures are best used with street tires on lower power and lighter bikes altthough many liter bike’s race tires are set cold in the mid 20s
 
A pair of WM 3s. I weigh 260. And, I should add that a greasy feeling results when the tires' tread overheats when lower pressures are subjected to time at higher speeds.

Forty years ago, when we raced in Griffith Park, where the road was tight, our average speed probably was under 40 MPH, we'd run K81s at 19 front and 16 or 17 rear. There were a couple of spots where we'd see high speeds, even 100, for a moment, and the bikes might wallow for that moment, but that was manageable and worth it for the traction obtained in the very slow corners. That road had many tight turns, was often dirty and it had a slurry seal surface, so traction at low speed was our priority. Similar to how dirt bikes' traction benefits from low pressures.
 
I tried to support a local industry, lesson learned, if you want no drama and what you payed for, buy off Buchanan's in the good old USA. .

I'm in Australia and am interested in who you dealt with - I'm looking at buying a couple of wheels in the near future and would like to know who to avoid.
Cheers
Rob
 
Anodised rims are cool TW, less corrosion, less polishing. Wish I’d had mine anodised.
 
What is the reasonable life expectancy of repro Dunlop K81 tires before the rubber becomes too hard?
Will they soften up again with use?

I have a set which look brand new.
They came on a wheelset I bought. No cracks at all but could be anywhere from 5-10+ years old.
 
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What is the reasonable life expectancy of repro Dunlop K81 tires before the rubber becomes too hard?
Will they soften up again with use?

I have a set which look brand new.
They came on a wheelset I bought. No cracks at all but could be anywhere from 5-10 years old.

Run them or replace?

I would run them but not at high speeds, but then who knows I am a cheap bastard sometimes lol.
 
It is tough to toss good tyres but then think of what the cost of a pair of tyres is compared to repair of the bike after you drop it.
...we will not discuss cost of repairing you!
Go order a set of tyres and mind the dates on those tyres.
 
Main issue is surface hardness/slipperiness that can put you on the ground.

I recently bought a T100 which had Indonesian K70s on it. Tread would not allow my thumbnail to penetrate. I took a big disc sander to both wheels, allowing the sander to spin each wheel while cutting the hard surface tread off. Might have taken 20 thou off before I got down to soft rubber.

I had no prior experience with K70s and did not have a high opinion of them, based on looks alone. I was wrong. The disc sanding worked and I have ridden the bike fairly quickly
 
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