Tire cupping alleviated by religious use of Center Stand?

[artemedes]

I was starting to notice the beginning of front tire cupping at around 3800 miles. Up to this time I had only used the center stand for maintenance or if I knew it was going to be parked for a few days. I probably check the tire pressure at least weekly and have an air compressor in the garage so I can easily keep the tires at Honda's recommended settings. I experimented by adjusting the pressure 3 psi in both directions and just found it ride the best at the recommended settings.

Anyway.....The only thing I have changed in the last 1600 or so miles is to use the center stand anytime the bike will parked for more than an hour. Not only is it much easier to get on it now, but I am pretty sure the cupping has gone away. It took a long time obviously. I wasn't expecting it to go completely away, but was just trying to slow the cupping process down. At first I thought (about 800 miles into experiment) it was just me and wishful thinking, but now I am fairly certain it is working better than expected. I think that the center stand not only alleviates pressure on the tires (so they are less likely to flat spot), but what pressure there is on the tire is in the center and not on the sides. Thus much reduced cupping.

By "religious use" I mean every time I park it for more than an hour. So at work, in the garage. I even use the center stand sometimes if I am visiting friends or family and know I will be there a couple of hours.

At this point I am about 5500 miles on bike and my cupping problem is practically gone and I feel confident I can get another 3000 miles out of the tires.

Anyone else using the center stand a lot? How is the cupping on yours?

 

[Mellow]

I use the center stand a lot on my past Wings and STs and Current ST and Tenere... so, between 2 sport tourers, 2 Wings and a heavy Dual Sport - no difference at all, the tires cup.

Cupping is more of a factor associated with acceleration and braking than it is any resting forces. Guys that don't engine brake much, don't take off from stops like a rabbit and aren't very aggressive riders typically have tires that last long and don't cup as much.

 

[Phil Tarman]

Rick, pictures I've seen of "toasted" race tires look way different from worn-out touring tires. For one thing, dry-weather racing tires are slicks with little or no tread to begin with. I'm guessing that they have a completely different kind of rubber. Toward the end of their lives, they'll have rubber balls on the edges rather than cupping.

I think cupping may have a lot to do with the tread design. I think cupping is a result of tread blocks moving in relation to the whole tire. (He says authoritatively even though he knows Jack Snit about tire design, construction or engineering.)

 

[DirtFlier]

Most car and motorcycle race tires have only minimal tread thickness when compared to a normal tire for a road going vehicle so "cupping" doesn't occur.

 

[Lorien]

An interesting thread. I assume you have the BS BT 020 tires. They have to be one of the softest OEM tires I have ever seen. Now I can believe that taking some of the weight off at night or whenever could effect the "flatspotting " as it were. Long ago on my ST11 I was surprised to see that turning the front forks would cause the center groove on the tire to deviate for a few milliimeters but the effect was temporary and lasted only a few minutes. Does not seem enough to cause uneven tire wear. Somewhere along the line I was told that cupping had a lot to do with front fork stability at speed. A great number of factors play into this equation but the idea is that the front tire is oscillating during rotation. The ST11 was famous for its ability to cup fronts regardless of brand. I remember being at a meet where 3 different ST11 of three different years manufactor had three different front tires and they were all cupped to a significant degree. The supposed fix was to replace the front fork head bearings with rollar bearings (the bike had ball bearings). Another fix for the problem via manufactors over the years has been to increase the size of the front forks to stiffen the entire assembly or for the owner throw in a fork brace. So the question becomes what does raising the front fork assembly at rest have to do with any of this? Hard call I think. Other than decompressing the front (and rear by the way) fork springs by being on the center stand I do not see a lot going on. May be a sticly valve in either the front or rear shock asembly that got better by being deloaded? Something of a long shot. So perhaps we're back to the tires. It is worth noting that the standard fix for this is to raise the inflation pressure so you might check and see if this has changed for some reason. I have gone to Dunlop Roadsmarts and the cupping has vanished so tread design does seem to be in there somewhere. An interesting observation none the less and worth trying for new owners. Might even let Mother Honda know about it.

 

[ARKNT]

My thoughts on cupping match Lorien's pretty close. My Connie front tire usually suffered from cupping and I adjusted, and replaced steering head bearings to try to stop it. I had used several different tire brands over the years and never really fixed it. The Connie came with roller bearings but were suppossed to be undersized as they were originally from a much lighter Ninga 1000.

I read somewhere and tryed a trick to lengthen out usable tire life if cupping gets bad. If the cupping is bad enough that you can feel it while leaning into a curve you can shave some of the high spots off the tire with a wood rasp type tool. I used a sharp open type and spun the front wheel while holding the tool lightly on the tire to remove the rubber on the high spots. Of course it is temporary but it can make the bike smoother when leaned over and add to the confidence level. The real answer is new rubber.

Brad

 

[elizilla]

If the tires are cupping because you have worn/notchy steering head bearings, that's a problem that needs to be addressed, not just for the cupping but in general.

 

[Phil Tarman]

If the tires are cupping because you have worn/notchy steering head bearings

My OEM BT-020s cupped pretty badly by 6K miles. Neither the BT-023s nor the ME-880 radial fronts I've had since have cupped at all.

I don't think I've got worn/notchy steering head beaings. Do you? Just askin'....

I just re-read your post, Katherine, and realized that you said "if" your tires are cupping because you have worn/notchy steering head bearings..."

I agree with your statement and don't think you were thinking I had worn/notchy bearings.

I gotta' work on my reading comprehension!

 

[elizilla]

Whereas I'm a more aftermarket kinda motorcyclist, I guess. The stock suspension, the stock steering head bearings, and the stock tires, are chosen for a price point rather than because they're the best choices for the bike. They're acceptable choices that will last just fine for the number of miles that the average rider will put on the bike before the warranty runs out. But the average annual mileage put on a motorcycle in this country is pathetic, so the OEM component longevity bar is set really low. You can get better performance, better longevity, and often both at once, in the aftermarket.

Suspensions are optimized for a particular rider weight. If your weight is too low for your suspension, things can get kinda sporty, and shade from there into dangerous, rather quickly. If your weight is too high for your suspension, things degrade less quickly, but at the extreme end this can get bad too - there are high limits and low limits. Honda doesn't want people getting killed, so the OEM suspension is optimized for the lightest person that's likely to buy the bike. If you're heavier than this theoretical lightweight rider, an aftermarket suspension can be optimized for something closer to your own lightest weight, which will be an improvement (for you) across the board, even when you load the bike down more than usual.

Steering head bearings, you get a choice of ball bearings or tapered roller bearings. The tapered rollers are more expensive and harder to adjust correctly, but they last longer. Ball bearings are more forgiving of ham-handed wrench turners, and will last long enough to get the rider out of warranty. Honda chooses the steering head bearing that costs them less and makes assembly errors less likely. But if you install the other type correctly, they'll be fine and they'll last longer. Six of one half dozen of the other; the only way you go wrong here is by doing the work badly.

 

[elizilla]

Also, tires are temporary. They're like gasoline - they're a commodity item. Buy whatever you think seems good, and if it turns out you don't like it, buy something else next time. The stock tires on the NT are probably Bridgestones because Honda is getting a deal from Bridgestone based on the sheer number of tires they buy, and the Bridgestone delivery schedule reliably meets their needs. And no matter what they put on, many people will choose different replacement tires. The NT isn't a performance machine where the magazines will praise their tire choice and make it a selling point. It's more like, "yawn, tires, yeah, guess we gotta have some."

If Honda strove for perfection in every choice, the bike would cost way too much and they'd never sell any. They call it "satisficing". The designers pick something that is good enough and meets the price point, and they move on.