Tire cupping. Replace???

[Kylenav]

I had a rear wheel bearing go bad a few weeks ago and while waiting for the bearing to come in I borrowed my friends rear wheel and tire.  After I put my wheel and AVON back on I noticed a slight vibration in the turns still.  Took a closer look at the tire and its got some cupping going on.  Is this reason for replacement?  It only has 2500-3K miles on it and I'd hate to change it so soon.

I guess I'm asking if it will harm anything on the bike. Such as the rear wheel bearings etc.  Any reason to think the tire could have a failure from the cupping issue?  If it's just the vibration and won't hurt anything then I'll leave it on until it's worn out and I will swap it for a CT.

I will mention this cupping is my own dumb fault.  When I inherited the bike from my father he hadn't been well enough to ride it for a month or so.  I was a little distracted and tire pressure was the last thing on my mind.  I rode it from Atlanta to Tampa and it was a couple weeks before I could bring myself to ride it again.  I checked the pressures and the rear was at a whopping 22psi.  I'm positive this is what did it and just need to know what to do from here.


As always thanks for any input!!!

[John Schmidt]

Kyle, you should be OK using it, just keep the psi well above 40 and an eye on the tire. Some riders have had problems with splits in the surface so watch for it. If you can handle the vibration you should be alright. If it's extreme and it were me....I'd make plans to change it out soon. In fact, it would have never gone back on. Keep us posted as it develops.

[Joe Hummer]

I have about 8k on my Avon rear tire and it has been cupped for several thousand miles. I just ride on until it needs replaced...which it is getting close...probably another 2k or so. I have noticed the vibrations also but have not had problems with handling.  Will be ordering a bridgestone G702 soon.

[The Anvil]

Yah, just inflate it to proper pressure (I run 44) and keep an eye on it but it should be fine.

[Daniel Meyer]

Agree with the posts above...air it up to 44 and run it. Watch the wear bars, but the cupping won't actually hurt anything.

[Mr Steve]

I guess I'll be the lone dissenter, if a tire on my bike cups I replace it.  Anything that effects, or may effect, my contact patch is of concern to me.   I figure a new tire is about the same cost as my ER co-pay but a lot more useful to me.

[MarkT]

Just FYI for your next tire install: One of the problems the dynamic balancers is supposed to prevent is cupping.  That is, Ride-On & Dyna-beads, to name a couple.  Of course, they should be used with appropriate tire pressure, as always. I'm running Ride-On on all tires on the wing and the valk, as of my last tire installs, and see no cupping yet - which I have seen before. I'm running not less than 38 on my fronts, which are bias-ply rear tires, and keep 42-44 in the rear Cobras.  BTW I've never had such a smooth ride as I do now, with Ride-On doing the balancing.

[The Anvil]

I guess I'll be the lone dissenter, if a tire on my bike cups I replace it.  Anything that effects, or may effect, my contact patch is of concern to me.   I figure a new tire is about the same cost as my ER co-pay but a lot more useful to me.

I can dig what you're saying, but unless it's cupped REALLY badly then it's not going to affect your contact patch. The rubber and carcass both serve to conform to the road surface enough to negate anything but the worst cupping/feathering and you'll still have plenty of rubber actually meeting the road surface. Especially on a big, heavy bike like a Valkyrie.

[Kylenav]

First off thank you for the reply's they are extremely appreciated.  That being said I'm usually all about riding it out and taking chances, however with this 5K plus ride I'm going to have to bend over and replace the tire.  I don't know what you would consider "extreme" but best I can measure/explain the "rear" portion of the tire grooves is AT LEAST 1/4" higher than the front, some places are more.  So when I rub my hand from top to bottom, away from handlebars, it is "extremely" noticeable.

So now that I have decided on a new tire before my Friday departure I have yet another question.  Sometimes this turns into a heated debate so I'm asking for just verified data and your personal opinions.  Hope that doesn't make me sound like a real prick, but I don't want to be responsible for a post being turned wrong...

General Altimax HP or Bridgestone potenza G109?  Or are they basically the same and I'll be fine either way?  They will be the same size, 205/60 R16 in the V rated form.  Prices are basically the same and not a deciding factor.

I have been reading about the CT for over a month, I just thought I would be doing this AFTER my ride, not a few days before.  I know the General is more popular but I'd have to order it and earliest it could be delivered is Wednesday. So I'd mount it Thursday and hit the road Friday early morning.  If Bridgestone is a close second or tied for first just the fact that it's in stock and can be done on Tuesday will push me that way.

Thank you all again, greatly appreciate your words of wisdom.

[PhredValk]

I'm not a real expert on the CT thing, I'm on my first. I would go with the Tuesday tire, as I would like to have a couple hundred miles on it at least to see if I had a problem with the tire. That gives you time to trade it out if you don't feel safe or there is a problem before starting out on a 5K run.
Fred.

[RonW]

I don't know what you would consider "extreme" but best I can measure/explain the "rear" portion of the tire grooves is AT LEAST 1/4" higher than the front, some places are more.  So when I rub my hand from top to bottom, away from handlebars, it is "extremely" noticeable.

I would consider a ¼-inch difference between the trailing edge and the leading edge of the lands between the tire grooves to be "extreme." ¼-inch is about the original thread depth on a brand new tire.

[Ricky-D]

I've had cupping on the front tire pretty much all the time when the tire gets a lot of miles on it and I have never let it bother me. Seems like the E-3 was always the worse in this regard.

I have never seen any trace of cupping on the rear tire however.  Now with the C/T's I still see no evidence as there was never any on the M/T's that I wore out previous to going DS.

I never considered pressure to be that big a player in the cupping phenomenon but rather a function of the turning and leaning/grabbing qualities of the tire as related to the tread design.  Seemed like tires that have the sipes that approach right angles to the rotation of the tire are the most prone to cupping.

If the tire that you are now determined to change out were to be pressured up, it may reveal that the areas of concern (cupping) are not even going to be in much contact with the road surface and therefore not to be troubled about.

***

[Farther]

Seemed like tires that have the sipes...
***

So, what cruiser tire brands have sipes?

[Ricky-D]

Seemed like tires that have the sipes...
***

So, what cruiser tire brands have sipes?

Well you did catch me Farther. I looked the word up in the dictionary, after reading your comment, and cannot find it. (sipes)

But: I seem to recall the practice of cutting slits/slots/grooves in tire was called siping or something like that so I just carried on, ignorantly at that!

Regardless, what I was trying to convey was that the edges of the individual small sections of the tread and especially the one's that run more or less, perpendicular to the rotation of the tire when it is on the pavement seem to be the places where the "cupping" occurs.

As poor an observation as this would be; I don't believe you would ever see cupping on a tire that has no tread such as a slick tire that is used in racing. I may even be wrong in that too.

Whatever, I think tire pressure has only a small part in that phenomenon.

Just as a note, it's possible to Google the word and find information on sipes. Some may want to do that!

***

[Mr.BubblesVRCCDS0008]

 Bridgestone potenza G109? I'm runing a bridgestone G 019 if that is the tire your looking at it'll be a good choice.  I've got about 10K on mine and still looks like the day I munted it. I run 36-38 psi in mine, too much will wear the center out premature.

[RonW]

Well you did catch me Farther. I looked the word up in the dictionary, after reading your comment, and cannot find it. (sipes)

Sipes is the proper terminology. That's not to say proper terminology should be de rigueur on a forum, but it doesn't hurt any to know what the 'terminologically' right noun is and often spares nomenclatures. Still there? I didn't even remember the term myself among with a whole lot of other things. Snipes derives from the name of the original patentee. But it's beyond me how he was able to obtain the patent, and later, Goodyear, since it would not pass the non-obvious requirement the biggest hurdle for a patent grant. No more than you could patent knurls where the risers clamp onto the handlebars to prevent the handlebars from slipping. Or crosshatching on gun stocks would be so non-obvious to the average person that it would provide a better grip that it's deserving of a patent.

[Mike]

Kyle, you should be OK using it, just keep the psi well above 40 and an eye on the tire. Some riders have had problems with splits in the surface so watch for it. If you can handle the vibration you should be alright. If it's extreme and it were me....I'd make plans to change it out soon. In fact, it would have never gone back on. Keep us posted as it develops.

I just noticed there were some splits in my rear Cobra. (9300 miles) I am very anal about making sure the pressure is good. (42lbs)

Have you heard what may be causing these splits.

[Farther]

There is a difference between sipes and grooves on a tire.  The sipes are more like cut and are applied during the manufactur or by a person (dealer) with a siping machine or by hand with a sharp blade.  The cruiser motorcycle tires are little more than grooved slicks and will never perform as well in the rain or on otherwise slick roads as well as a siped tire.  I guess my google works better than yours.  Here is a link to a dealer site: http://sipers.com/testimonials/ and http://www.discounttire.com/dtcs/tireSiping.dos 

[Tundra]

Kyle,
Congratulations on your new CT.
(you can get your cookie and Darkside sticker from TJ) Play with it and you'll find your tire pressure sweet-spot that works for you. Everyone is different, mine is 33psi solo and 38 psi with gear and two-up. By the time you get back from your 5-7k roadtrip, you'll be giving others advice.
  You've had that rear end off more times this month than I have total. Now quit working on it and ride it.  Have a great trip and take lot's of photos, wish I could go with you.

[Kylenav]

Thanks again everyone for the info.  As TUNDRA stated the new tire is on, the G 019 sorry for my typo, and it is awesome.  Rode it today for 100 miles or so and feels like I've been riding dark side all my life.  It is absolutely amazing how much rear brake you gain with the CT.

I'll be adjusting the air pressure for a while just to see where I like it and I'm adding Ride-On before my journey front and back.

Thank you all again very much for the very helpful information!

Kyle

[toetruck21]

Well you did catch me Farther. I looked the word up in the dictionary, after reading your comment, and cannot find it. (sipes)

Sipes is the proper terminology. That's not to say proper terminology should be de rigueur on a forum, but it doesn't hurt any to know what the 'terminologically' right noun is and often spares nomenclatures. Still there? I didn't even remember the term myself among with a whole lot of other things. Snipes derives from the name of the original patentee. But it's beyond me how he was able to obtain the patent, and later, Goodyear, since it would not pass the non-obvious requirement the biggest hurdle for a patent grant. No more than you could patent knurls where the risers clamp onto the handlebars to prevent the handlebars from slipping. Or crosshatching on gun stocks would be so non-obvious to the average person that it would provide a better grip that it's deserving of a patent.

WOW, I thought I was somewhat educated but can I borrow this for or site it as a reference in my English master's program.  My head is still spinning!!  I like it!