Just got the following comment about the Avon Triple Duty tire and wanted to get any thoughts on correctness of the comment.
"One of the hardest things you can do to this tire is run it at highway speeds above 55 mph for a prolonged time and then through in a head or cross wind and maybe a few hills, this will shorten it's life and cause pronounced cupping. The tire has both a low speed and weight rating which also is a contributing factor. As well as many others and I used trials type tires, which are soft and have almost the same block type pattern as the Avon Sidecar, on our rigs for a lot of miles and these block patterns would wear the same way, although on some rigs worse than others, but to some degree they all had cupping."
I've run through a bunch of them on my bmw r100 rig, mostly with good wear. They do have a very low speed rating (I think 73mph or 77mph tops), and I have had trouble getting some of them to balance.
What are you using it on? What is the rear tire you are using it with?
I've had better luck on my bmw r100 using an avon sm 3.50 rear on my 19" front and an 4.00 avon sm rear on the 18" back. The avon sm is a heavy duty, near square tire, with a higher speed rating, that avon suggests for sidecar duty, available in the taller, high profile 18" and 19" sizes needed for vintage bikes.
Usually I've run a Metzler k-block 4.00 18" rear with the avon triple duty. The avon sm usualyy out lasts the metzler by 20% or more.
I just changed everything over to a '98 1100 Virago. I'm using a Metzeler ME880 Marathon 140/80 15" on the rear. I noticed the Avon SM 3.50 19" before but never thought of putting a rear on the front. Their S-rated up to 112mph. The Triple Duty is L-rated up to 75mph.
I've have a 3.50 Avon MK II 19" tire on the front of my R75/5 for the last 4 years. I put about 19,000 miles on it so far..same tire, no cupping , slight wear. speeds up to 95. I cruised all day at 80 with no problems.
also have an 18" Block K on the rear...they last about 8,000 miles each.
http://www.jpcycles.com/productgroup.aspx?GID=20C7B2EE-5088-4436-9501-18E16D310FAE&brand=avon
On my new K bike rig, I will be using the 4.00 18 Block K on the front wheel.
Never any real complaints with cupping on the avon. Have replaced them due to weather cracking though. Wear factor was okay depending on how the rig was ridden. Good as any and better than some from my experience. Those speed ratings are for 'sustained speeds'. Not too many sidecar rigs sustain a real high speed under typical conditions. I had been told the term 'tripe duty' was an old way of saying that tire could be used on any wheel of the sidecar outfit.Who knows..sounds good anyhow.
Thanks for the replies on the Avon Tripe Duty tire. Conclusion - it ain't the tire that causes the problem.
