My rear tire is badly cupped with only under 9k miles, but doesn't give me any feeling of being unsafe .... just have to hear that irritating howl when not riding on the center of the tire. Tire pressure can't have ANYTHING to do with it on mine because I check them EVERY time before I go out, yes I'm that ****. I always run the rear at 40-41 and front at 36-37. I think the only reason Dunflop stays in business is from selling HD so many garbage tires on all their new bikes. I don't know anyone that ever buys their fkn junk tires again after wearing out the factory ones. Once this pos is worn down I'm going with the Commander II again. I had this same problem on my old RGU and replaced the rear around 13k miles with the Commander II and was a night/day difference ... only sad part is I didn't keep the bike long enough to see how it lasted against the junk Dunflop.

 

My last two bikes, post 09, both had cupped tires, but they lasted much longer than the 06 rear tire did, I got over 20 k's on the 14. I put CII's on it, seem much better, but time will tell, . Question , if you don't rotate car , truck tires, they will cup also, there is no rotating on a bike, so are they engineered to not cup ?

 

Looks like you guys need new tire guages

 

They say it's tire pressure related. But I'm leaning towards it being the stock dunlops are not the right tire for the weight of our motorcycles.

 

Like I said earlier, I check my pressure religiously, at least once a week. I am also a year round rider, so I keep a good knowledge of my tire condition. Others say I fixate on the tires, but there is not a lot touching the road on a bike, so I'll take it.

Regarding gauges, I have checked with multiple ones...including a calibrated one at work, just to make sure mine was correct.

I didn't notice any loss of grip from the cupping, but then I don't ride it like a sport bike either.

I do like the American Elite I put on about 5000 miles ago.

 

Has anybody with the tire and wheel coverage tried to get their cupped tire replaced under warranty recently (within the last couple years)?

Other threads I've read seem to indicate that the MoCo is not replacing tires just because they're cupped, but most of those threads are pretty old.

 

You might be thinking of the front tire on the 09 Touring bikes. Originally it was a D407 but that was replaced by the D408F. The tires looked the same but the thread pattern was reversed. I think a Tech Service Bulletin was put out about #M1258A of Nov. 4, 2009

 

Only one entry has specified the pressure he maintains. You could stop every mile and check your pressure but if you are maintaining a pressure too low all of that effort would be wasted. Tire pressure is like religion, everyone has his own belief.

One of the few facts for tires is that heat is the enemy, the hotter a tire gets the closer it is to the temperature at which it was made and therefore can become "un-made" (come apart or blow out). The only thing effecting temperature that the rider can control is air pressure. Low pressure causes a lot of carcase flex generating extra heat and high pressure generates little flex minimizing heat generation. Heat also softens the rubber increasing wear. The max pressure on the sidewall is for the max load for that tire. Harleys are big bikes and don't miss that max load by much especially two up and with baggage. Being naturally lazy I don't want to bother changing my tire pressure for each ride so I maintain the max sidewall pressure plus a few psi to allow for any seepage between checks and also to be on the safe side if my gauge reads a pound or two higher than actual pressure. In hard numbers, I run a tire with a 41 psi max inflation at about 45 psi and look at that 41 psi as the absolute minimum that I will allow. The bike owner's manual pressure is too low.

My experience is that I get better than average tread wear and cupping is only slight when it happens. As stated above, tire pressure is personal belief and I have explained the reasons for my belief. Take it or leave it as you see fit.

 

I also believe that the cupping is on how aggressive you ride. I usually only get a small cupping on the tires. However after one trip with the guys, the wife did not go that year. We were running a "bit" hotter than usual. About 3,000 miles all over the Smokies and down the Blue Ridge Parkway the rear tire was very much cupped. Tire pressure was right at 40 psi every morning on the cold tire. When putting 300 plus miles every day I check them every day before leaving the hotel. Anyway when I got back home I tried the belt sander thing I heard about but that did not work for me. But putting the bike on the lift and starting it in first gear. Just let the clutch out at idle. Held a Surform up to the tire and it just pealed off the excess rubber. Just took off the high spots on each side. Kept the rounded profile and it was super easy. Took longer to put the bike on the list that to shape the tire.

 

btsom, good point. I didn't feel like quoting what you said, but well said.

I run 38 Front and 40 Rear.