Tire cupping

Why do u get cupping on the outer side of the front tire?
i have noticed it on my KZ's Michelin pilot sport, and a couple friends say they have the same issue on there newer sport bikes.

Show a picture.

Cupping is generally caused by low air pressure. Roy

Mark, remember that our bikes are much heavier on the front end than modern bikes. If the front end is raked than it is even worst. New bikes have less caster than our bikes and are lighter. you might want to run about 5psi more in the tire than recommended.

Cupping on my truck was from bad shocks.

Low Pressure? Well thats good to know .
Thanks.
It wont show up in a pic Otto. i can only barely see it. I can and feel it if i run my hand over it.
My friends have gsx600 and R6, they have the same problem.
Maybe they are running under pressure?
I know i had low air in my tires early this summer. Hopefully thats all it is.
I am in need of a new rear, i may as well get a front tire too. i am going to try the Michelin Road 2's.Sport tour. they are a dual compound tire. softer on the side than the center.
I found the Powers wore out to quick. i only have about 4500 moles on the rear. No burnouts either.
The road tires are made for heavier bikes too , so that may help.

i would never use anything but Avon. Hell, if they're good enough for Rolls and Bentley they're good enough for me. :woohoo: Really they are the best kick for the buck. I have been running them since the late 70s and i would never switch back to anything els.

Some tires are just prone to cupping but any tire will have accentuated wear problems if asked to run under inflated. I check my tire inflation weekly. You would be surprised at how many times I've taunted a riding buddy into checking his tires while I'm at it and watched his expression when he finds 22 PSI in one or both tires.

It doesn't take long to cause noticeable wear if the tire is underinflated. One 120 mile ride can do it.

Bill

It is very surprising, how they can get low without u knowing.
Otto, what kind of Avons do u run? a sport , sport tour? what king on mileage do u get out of them?

mark1122 wrote:

It is very surprising, how they can get low without u knowing.
Otto, what kind of Avons do u run? a sport , sport tour? what king on mileage do u get out of them?

I get around 15k or more on mine. I liked the Roadrunner (AM20/21) but that was discontinued this last year. The replacement is the "Road Rider" (AM26) The best is the venom (AM41/42) but it is a little more money. Yes and they also have tires that are quite a bit more expensive, but I find them a waste. I run plenty of ponies in my bikes and ride quite " Sportingly", and I have never had problems with the less expensive ones. Made in U.K.
www.avon-tyres.co.uk/motorcycle

Here's another option. On my '77 KZ650C1, I recently replaced my Michelin Macadam tires with Pirelli Sport Demons. The Michelins caused a speed wobble after a few thousand miles even though they looked ok. The Pirellis have better traction, particularly in braking, than the Macadams. I used a 100/90 V 19 on the front and 120/90 V 18 on the rear. These are the same tire sizes as the Macadams I replaced. I have put a little over 1,000 miles on the new tires, so I cannot give a long term opinion, but so far I really like them and they show no wear yet. These tires have a modern asymmetrical tread pattern similar in appearance to some radial tires. The link shows the tread pattern. I bought mine at Ron Ayers. Ed

Pirelli Sport Demon

Thanks.
I just heard back from another rider. he said that cupping can come from improper suspension damping adjustment.
There is a lot of info to read at this site. i have not read it as yet, but thought i would pass it on.
feelthetrack.com/tuning_guide.htm