jporter12 Posted August 25, 2010 Report Share Posted August 25, 2010 After discussing the cupping on the front tire of the Ninja, a friend (long time rider, Harley engine builder) sent me this link from a BMW rider's site:http://w6rec.com/duane/bmw/cupping/index.htmThe cupping that I'm experiencing is not affecting the bike in ride quality or handling at all, just something I've noticed. Quote Link to comment Share on other sites More sharing options...
chevysoldier Posted August 25, 2010 Report Share Posted August 25, 2010 My tire is wearing more on the left side than the right. Need it replaced now too. Quote Link to comment Share on other sites More sharing options...
jporter12 Posted August 25, 2010 Author Report Share Posted August 25, 2010 My tire is wearing more on the left side than the right. Need it replaced now too.Look at the roads, and you'll have you answer to why. Quote Link to comment Share on other sites More sharing options...
Radio Flyer Posted August 30, 2010 Report Share Posted August 30, 2010 EDIT: Should have read the article. Quote Link to comment Share on other sites More sharing options...
serpentracer Posted August 30, 2010 Report Share Posted August 30, 2010 most tire experts agree a cupping tire is caused solely by low psi.some tires are just more susceptible to cupping than others too. based on it's tread and belts design. Quote Link to comment Share on other sites More sharing options...
MidgetTodd Posted August 31, 2010 Report Share Posted August 31, 2010 The cupping that I'm experiencing is not affecting the bike in ride quality or handling at all, just something I've noticed. I'm gonna say it is affecting it, you just don't notice it because it's came about gradually and you're used to it. Put a new tire on and you'll see just how much of an affect it really was. Quote Link to comment Share on other sites More sharing options...
jporter12 Posted August 31, 2010 Author Report Share Posted August 31, 2010 I'm gonna say it is affecting it, you just don't notice it because it's came about gradually and you're used to it. Put a new tire on and you'll see just how much of an affect it really was.BUT, what sort of effect would it have? Would it be less grip? Just a vibration when leaned over in a curve? I'ma google it, too. Quote Link to comment Share on other sites More sharing options...
MidgetTodd Posted August 31, 2010 Report Share Posted August 31, 2010 All of the above plus a few. Quote Link to comment Share on other sites More sharing options...
jporter12 Posted August 31, 2010 Author Report Share Posted August 31, 2010 Well, since it's not cupped very bad, I'm going to see if raising the air pressure will help take some of it out. From what I've read, heavy braking with the front brakes will contribute to cupping, which is something I don't do on the Ninja so much, I downshift that thing most of the time. Quote Link to comment Share on other sites More sharing options...
Whitey1 Posted August 31, 2010 Report Share Posted August 31, 2010 Well, since it's not cupped very bad, I'm going to see if raising the air pressure will help take some of it out. From what I've read, heavy braking with the front brakes will contribute to cupping, which is something I don't do on the Ninja so much, I downshift that thing most of the time.Brake pads are cheaper and easier to change then clutch discs. Quote Link to comment Share on other sites More sharing options...
MidgetTodd Posted August 31, 2010 Report Share Posted August 31, 2010 Well, since it's not cupped very bad, I'm going to see if raising the air pressure will help take some of it out. From what I've read, heavy braking with the front brakes will contribute to cupping, which is something I don't do on the Ninja so much, I downshift that thing most of the time. Has to do with the quality of the tire as well, what tire and pressure are you using. I only run 28-30 in my front and brake the hell out of it, no cupping. Quote Link to comment Share on other sites More sharing options...
jporter12 Posted August 31, 2010 Author Report Share Posted August 31, 2010 Brake pads are cheaper and easier to change then clutch discs.Who said anything about a clutch? In my laziness, I've learned the art of clutchless shifting, up and down. It's really easy, and not destructive if it's done properly. I'm more worried about the clutch cable than the discs.Has to do with the quality of the tire as well, what tire and pressure are you using. I only run 28-30 in my front and brake the hell out of it, no cupping.I'm running the Battlax BT45, which is a good all around tire for the smaller bikes. I have them on both bikes, in fact. I'm running around 30-32 in the front now. I think the OE spec for the front was 28, and I was running it there for a while, but now that I've improved my abilities beyond puttering around town, I'm trying different things to make the bike work better. I know, the first thing would be to replace the bike with something better, but that isn't an option right now, and the Ninja's probably going to stick around anyway. Quote Link to comment Share on other sites More sharing options...
Moto-Brian Posted August 31, 2010 Report Share Posted August 31, 2010 Look at the roads, and you'll have you answer to why.You guys that think you will wear the shit out of tires on the left side moreso than the right are insane. If you rode 20,000 miles solely on an interstate, maybe.Wear is going to be SLIGHTLY more left of center, but not by much. If you rode straight up and down on a 33 degree banking, you'd wear the shit out. Off a crown on a lane on a freeway or back road? Seriously...Cupping is just as Serpent stated... Quote Link to comment Share on other sites More sharing options...
jporter12 Posted August 31, 2010 Author Report Share Posted August 31, 2010 You guys that think you will wear the shit out of tires on the left side moreso than the right are insane. If you rode 20,000 miles solely on an interstate, maybe.Wear is going to be SLIGHTLY more left of center, but not by much. If you rode straight up and down on a 33 degree banking, you'd wear the shit out. Off a crown on a lane on a freeway or back road? Seriously...Cupping is just as Serpent stated...I thought I had put the after that! You are correct, it has near zero effect on tire wear. From what I've read: We drive on the right, making left turns wider, and faster, and typically with more lean, causing the left biased tire wear. Supposedly, in countries where the drive on the left side of the road, they have right biased tire wear. Can anybody back that up, or put bust the myth? Quote Link to comment Share on other sites More sharing options...
Moto-Brian Posted August 31, 2010 Report Share Posted August 31, 2010 I thought I had put the after that! You are correct, it has near zero effect on tire wear. From what I've read: We drive on the right, making left turns wider, and faster, and typically with more lean, causing the left biased tire wear. Supposedly, in countries where the drive on the left side of the road, they have right biased tire wear. Can anybody back that up, or put bust the myth?I still don't buy it. That would mean you turn left more than you do right. The bottom line is that these guys with blogs are about as accurate as the weather man.Truth is found in what Serp stated where PSI has more to do with everything than the crown, the amount of turns, etc.Of course, there's no way to see if there are people that turn left more than right...The idea on wear and the back edges getting pulled up is true. We see it on race DOTs a lot, but again, that can be cured or changed with PSI. Tire pressure is a funny thing and when asking people, you'll get anywhere from 25-45 in what they run. Some guys run what is listed as cold max PSI on the sidewalls!!! Quote Link to comment Share on other sites More sharing options...
jporter12 Posted August 31, 2010 Author Report Share Posted August 31, 2010 I still don't buy it. That would mean you turn left more than you do right. The bottom line is that these guys with blogs are about as accurate as the weather man.Truth is found in what Serp stated where PSI has more to do with everything than the crown, the amount of turns, etc.I was referring to the left wearing more than the right with that last post, not the cupping. I'm not debating what causing the cupping, as I pretty well agree with what causes it, being tire pressure, and tire design.Now, how about some good explanation for why tires typically wear out on the left faster than on the right on street bikes, in the US. Quote Link to comment Share on other sites More sharing options...
Moto-Brian Posted August 31, 2010 Report Share Posted August 31, 2010 I was referring to the left wearing more than the right with that last post, not the cupping. I'm not debating what causing the cupping, as I pretty well agree with what causes it, being tire pressure, and tire design.Now, how about some good explanation for why tires typically wear out on the left faster than on the right on street bikes, in the US.Again, the wear is so trivial if at all vs the right. I've seen guys that do serious sport touring and never saw a tire worn on the left more than right. Plus, it would be just a hair off center. Again, the banking at Daytona idea here. That link with the cords showing on the left and bald on the right. Stupid and honestly, not much more than the other side. I also question the pic because it is so far from center. But, that pic shows the right being so bald that it was probably so close to showing cords that again, very trivial. For someone to ride on tires in such condition, they obviously never maintain their bike and something else could have contributed.Roads all may have a slight crown. Some more than others. Some not at all. I am not going to sit and believe the wise tail you're spinning here. What I would do is maybe email your theory to Rider magazine or something and have them do a real world test. I'm going to say that the number of miles to show the difference is going to place you so far beyond the life of the tire that you are putting your life at risk. Quote Link to comment Share on other sites More sharing options...
RSparky Posted September 2, 2010 Report Share Posted September 2, 2010 I ran my front until it was near bald... I had a lot of cupping. The main cause for that I believe is the tread pattern of the tire. Each piece of tread (separated by cracks that allow water to flow) acts like an eraser on a pencil held vertical. When scrubbed, the edges wear more because the rubber is pliable and the edge is pulled down to contact the road more. My front also had more wear on the left. Besides the road crown theory, there is another explanation, probably what is described in that article. We don't turn left more than right, per se, but the circumference ofa left turn is greater that that of a right turn, on a two lane road. Therefore, the left side should experience more wear. It may not seem like much, but I'm sure it adds up, considering the fact that all roads/intersections require a turn.Just my .02 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.