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Discussion Starter · #1 ·
As a "new guy", I continue to read this thread with great interest, and although I'm nowhere near ready to try it, I do agree that new ideas sometimes meet with resistance from those who close their minds to them, so I'm trying not to do that.

But I guess I'm still "stuck" on one point. I agree that you are getting better tire milage, better straight line traction, and probably getting a better ride as long as you ride in a manner that keeps the tire tread relitively flat to the road surface and keep the tire pressures in a reasonable range. All those make sense to me. And I also agree that I've seen other bikes (mostly HD's) with similar tire profiles on them.

What I haven't come to grips with yet is how a "flat" suface (the tire tread) maintains a good measure of road grip as the lean angle increases.

You guys have a lot more experience with this than I do, and I will continue to monitor your progress in this experiment, but I'm not willing yet to say that it's either a good or a bad idea for me personally to try, so I'm not looking for you to "convince" me of that either one way or another.

What I did want to convey to you was that I applude your willingness to try this experiment, and, like I said, I will continue to watch it's progress with great interest.
 

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The CT will stay flat riding around a curve because the sidewall flexes outward and lets the tire stay fairly flat on the road. Most of us use run flat tires that have stiff sidewalls but they still flex because we run the pressure at 28 to 32 psi and this allows the tire to flex. I have had several other riders follow me and watch the tire as we go around curves and they have all said that the tire stays fairly flat on the road and the side does the flexing to keep it there.
 

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The CT will stay flat riding around a curve because the sidewall flexes outward and lets the tire stay fairly flat on the road. Most of us use run flat tires that have stiff sidewalls but they still flex because we run the pressure at 28 to 32 psi and this allows the tire to flex. I have had several other riders follow me and watch the tire as we go around curves and they have all said that the tire stays fairly flat on the road and the side does the flexing to keep it there.

+1
I wasn't convinced of this when I followed a friend of mine running a c/t. I witnessed for myself, you will have more tread on the road with a c/t than m/t in the curves and on the straights.
 

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The car tire doesn't perform like a steel wheel or even a hard rubber wheel. It reacts to pressure and deforms to maintain a lot of contact with the road.

The higher the pressure, the less deformation you get. So the lower pressure you run (like 30) the better traction you will have on the corners.

Getting a runflat will give you better sidewall stability when running a lower pressure.

Now, jump in and enjoy the ride!
 

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Not a great diagram, and a bit extreme, but you get the idea....


 

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Let me try to explain. Nothing else to do, too cold to go do any work.

I went to the CT not because of increased tire tread wear. I could care less if I have to put on a new tire twice a year. I wanted a safe rear tire.

I have had two very close friends go down due to tire failure. The tires were not worn out, there were in good shape and tire pressures were checked or on one case maybe, sure they were the first day, maybe not the second. Somewhere along the lines something goes wrong. A small puncture, or road damage , something. So it is what two hours between gas stops and you are running down the big slab running 75 or better making time, headed for your goal some 2500 miles to go. You gain the puncture along the way, the tire pressure goes down, the tire heats up, and it is summer and temps in the 90 degree range, heat waves coming up off the pavement.
For whatever the reason the tire blows. Loss of life and serious injury is the result, and the Life Flight Chopper carries you or them to the nearest trauma center. If you are lucky and have serious enough injury, maybe you will be killed instantly, sure not my desire to sit in a wheel chair.

Got your attention yet?

A motorcycle tire on the 1800 is very well designed, it has a rounded profile to obtain the maximum handling available on a motorcycle. It is however subject to road damage, and my original intent was not to replace the handling of the motorcycle tire, I like I say wanted a safe tire.

A run flat CT is a tire originally designed for the use on some of the newer sport cars and with the invention of the Run flat and the rim on the 1800 it was simply found that they very much are compatible to each other. A run flat is so designed that if you wish you can take a two inch hole saw and cut circles out of the tire, or slice the tread with a knife and it will hold you and the bike up, and safely take you to town, or the nearest shop to obtain service. The way they word it by the manufacture is something like at 50 miles per hour for 50 miles or something like this. Sure you will need a new tire or I would chose to do so, and yes there may be mounting problems but not going to get into that right now, the main thing is the tire is not going to blow out, de-laminate and cause you injury or death. A run flat with no air in it or low on air, will indicate to you that there is a problem, as it does get to acting a bit like a squirrel, you will be able to tell it is low on air or has no air. Especially going around a turn. So you can stop and plug it or go on to town, your choice. The main thing is, it will not blow out. It will not roll off the rim, it will just take you to town.

As far as road contact with the ground, the 1800 is not like other motorcycles. It is a favorite ploy by soothsayers to say we run on the sidewalls of the tire, and things like this. The fact of the matter is the maximum lean angle that you can obtain on the 1800, will never lean the bike over far enough to even fully use the edge tread even on a modern CT. You can grind the pegs off and put holes in the plastic lower cowlings and still the edge tread on any tire is not touched.

A motorcycle tire is made with a round profile, and for 90 percent of riding it has a very narrow contact surface with the road. On the 1800 maybe riding straight up it has a two inch or less contact patch (width) on the road. As the tire leans into a turn it actually loses a bit of contact patch for a short time then as you go over gains more, a motorcycle tire is designed when running full over at maximum lean angle to have the most contact patch at this time. (thing is the Wing never makes it) The belts in the motorcycle tire are laid in a way to provide sidewall strength, and to make sure the tire holds the road and does not flex and lose traction in a hard lean over turn. The tire compound is also formulated to be a bit hard to provide support.

Not needed with a big touring bike, lean angles are never fully reached.

A car tire on the other hand is flat. The ones we are using yes do have a rounded profile on the edge, but still flat. Mine do not flex, I am quite sure my Kumho does not flex, it has very stiff sidewalls and just by that very fact lends itself to work very well with the 1800. At the lean angle obtained by the 1800 it holds the tire that does have a somewhat softer tire compound to the road, it does not flex and lose traction. It keeps it planted on the road. Softer compound planted on the road equals better traction.

Straight up you will have depending on the tire, at least 7 inches of contact area on the road, as you lean the bike over to the maximum lean angle that you can obtain with the wing you will still have a minimum of a bit over 2.5 inches of tread contact with the road. More contact with the road with a Car Tire at all times than with a motorcycle tire. At the lean angle of a Wing, the full over lean angle such as a motorcyle tire is designed for is not a factor, a motorcycle tire has maximum road contact area in its full road racer lean angle. Not a factor with a big touring bike.

Put it all together and you have a situation where you have a tire that has more contact area at all times than a OEM tire. Softer compound , better traction, better braking, and especially better traction in the rain.

Many will play the hydroplane card, not stopping to realize that the CT has so many more tread cuts that develop traction on the road a MT cannot even compare. All tires will hydroplane, so I for one just slow down, or pull off the road and wait for the heavy rain to stop. As for wet roads and light rain, hey, if you want traction you have it.


As for feel and handling, just something you will have to go do and find out for yourself. A CT likes to tail kick to the low side of the road a bit, not serious and in less than 100 miles you will learn to just lean or shift your weight a bit. There will be a bit different feel in the curves, hard for me to explain it really, but basically you do drive the bike into the curve, there is a point of turnover where it actually starts to perform better than a MT. Then with practice and more practice and as you become comfortable with it, learn that a bit of power will pop the bike up and allow you to instantly turn into the next one.
I actually prefer the feel of the CT versus the MT. You may not, and no one thing suits everyone, it is just something you have to go play with and learn for yourself.

The bottom line is I am now very comfortable on a long run, running fast and going long distances. It is very rare for a front tire properly maintained and checked to blow, very rare, but not so rare for the rear one to pop.

That was my original reason, since then I have realized many more advantages to the CT. It has became my preferred Tire. I and my Kumho will make a fall run this fall of about 7000 miles round trip. I for sure will not be worried about no tire.

Kit
 

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NH1800,
Only thing I can tell you is that the bike will run out of lean angle way before the car tire will run out of traction :yes1: ! In my opinion, the car tire has more traction in the rain on straight or twisty roads also :smile: !
 

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Discussion Starter · #8 ·
Let me try to explain. Nothing else to do, too cold to go do any work.

I went to the CT not because of increased tire tread wear. I could care less if I have to put on a new tire twice a year. I wanted a safe rear tire.

I have had two very close friends go down due to tire failure.
...............................................................................................
As for feel and handling, just something you will have to go do and find out for yourself.

Kit
That I can relate to also. I have never had a tire fail or go flat on a trip, but my trips rarely exceed 3000 miles at a shot and I always put on a new set of tires before I leave (allowing time for scrub in - of course). I still can't help but think about what would happen though if one did fail and it would not be pretty. And I have often wondered why MC tires were not made to "run flat" or at least self seal.

Similar thoughts are why I gave up riding chain driven bikes in the 70's and went to the BMW's shaft drive. I did have a chain break and lock the rear wheel once and that once was enough for me. Since then I have never owned another bike with a chain on it.

One of the guys I was riding with up in Nova Scotia last year did have a front go flat on an FJR, but that was due to a nail and the tire went down slow enough for him to control the bike. Still, it was interesting to be behind him and to watch how the bike reacted. Personally, I've never been on, or seen, a bike actually go down because of tire failure.

I did watch the video on the web that showed the Wing and the view from both the drivers view and the tires view. Un-like most, I could not help but think that only about 1/4 of the tire was on the road in some of the corners. And I wondered about the "transition" from flat to edge as the bike leaned over. Of course, I have no idea of how much of a MC tire is on the ground when you turn either, so I have no comparison.

Also, it seems to me that the "old" motorcycle tires I saw as a kid on the local HD's were a lot squarer than todays MC tires are. That's just an impression and, for all I know, those guys were running CT's even back in those days.

So, I still wonder about the cornering issues. There may be non for all I know and I also understand that no matter how much I "read" about this stuff, or how many videos I watch, the only way I will ever find out is to try it for myself.

I just need to get myself more comfortable with the idea I guess and that may take me a while. Us "old dogs" don't learn new tricks very easily sometimes :lol: So excuse me if I pop up with some weird questions or comments, it will mostly come from ignorance on the subject.
 

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I have to agree with everything that has been posted. I would add that the pressure really does make a difference so you will need to experiment to find your ideal weight. For commuting I prefer mine with a bit more pressure (38 PSI). For a bit more agressive riding I prefer 31-33. The tire seems to perform equally well at either pressure but at a higher pressure the edge seems to be less pronounced and feels a bit more like a motorcycle tire.

I have a bigger problem with the front end sliding than I do traction on the rear.
 

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NH1800,

I found this on you tube. Thought you might enjoy it. It shows you just how much rubber is really on the road in turns.

Enjoy;

John
 

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Discussion Starter · #11 ·
NH1800,

I found this on you tube. Thought you might enjoy it. It shows you just how much rubber is really on the road in turns.

Enjoy;

John
Thanks John

Am I wrong or does that tire have a more rounded outer edge than the others that I've seen pictures of here? But, you're right. I think this one has plenty of contact area.
 

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Steve,

I'm glad you are researching this. I did the same thing. I read this board for a year before I went to a CT. I didn't know what to expect, but all I can tell you is that I have better traction, smoother ride and my wife says I lean more in the corners than I did on the MT. The more I ride it the more I love it. Not sure what else to tell you....you just have to ride it to understand. Come by sometime and try mine. It will win you over. One of my friends I ride with also has a wing and wanted to try the CT. We traded bikes and he wouldn't give mine back until we got home! He was all smiles and hasn't given me a hard time about the CT since. As they say on TV, "Try it, you'll like it!"
 

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Discussion Starter · #13 ·
Steve,

I'm glad you are researching this. I did the same thing. I read this board for a year before I went to a CT. I didn't know what to expect, but all I can tell you is that I have better traction, smoother ride and my wife says I lean more in the corners than I did on the MT. The more I ride it the more I love it. Not sure what else to tell you....you just have to ride it to understand. Come by sometime and try mine. It will win you over. One of my friends I ride with also has a wing and wanted to try the CT. We traded bikes and he wouldn't give mine back until we got home! He was all smiles and hasn't given me a hard time about the CT since. As they say on TV, "Try it, you'll like it!"
Well, I don't want to be one of those guys who just says "He**, that'll never work." without anything that truely convinces me of that. And, anything that has 300 guys raveing about it just can't be ignored out of hand. However, I also realize that 300 out of all the guys on this site is not a large sample (although I'm sure there are far more guys around the country doing it than just you guys).

I think one thing out of all that's been said really interests me about this. That is the "run flat" aspect. I don't really care about getting 20,000 miles out of a tire (although that would be nice), but maintaining the current handeling and getting a rear tire that wouldn't instantly come apart when it went flat has an appeal. Also better "wet" traction has a great deal of interest too.

If I ran all highways, I would probably do it without looking back, but I run tons a little 2 lane back roads and the handeling there is important to me. Enough so that as soon as the weather clears, and even though it only has 3,000 miles on it, the bike is headed over to get a full Traxxion make over.

I do appreciate your offer of a ride, but by the time I got from NH to Texas and back (and paid all those motel bills), I could have bought a spare rim and tried it for myself - LOL :p:p:p:p:p:p
 

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Steve,
I'm glad thet your mind is "open" enough to at least explore a new idea.

I concure with all the above posts. What I found was the very stable handling around all the twistys we have around here.

The ride is vastly improved over a MC tire.

The handling is different, not bad, just different.

I too reasearched for quite a while before I went to the darkside and when I did I went double dark with a rear MC tire on the front.

I noticed that you don't have Colorado colored in yet. Come on out and we'll fix that !!

Good luck with your quest.
 

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Discussion Starter · #15 ·
Steve,

I noticed that you don't have Colorado colored in yet. Come on out and we'll fix that !!

Good luck with your quest.
No I didn't get over there on a motorcycle. I did go over there skiing quite a bit when I lived in Salt Lake in the late 70's, but never on the bike. Pretty country, especially West of Denver - LOL.

But, that's why I have two "strips" colored in with nothing in between. I lived in SLC from 75-79 and then when I came back from SLC, I sold my bike there and then bought a new one when I got back here.

I'm planning on retireing (no pun intended given the thread I'm on) in the next couple of years :)bow:) and I hope to fill in a lot more of that map after that.

This year I'm doing 2 weeks up on the Gaspe and then down thru PEI and the Maine coast.
 

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The one thing I didn't realize with the C/T is how much tread is on the ground compared to a M/T by looking at the side view of the tire. I'm running about 35 in my Kumho and by looking at the side view of the tire, I have 5 to 6 inches on the pavement. It is a good size patch. As soon as I can figure out how to get a footprint of a m/t on the sidestand and the same of a c/t, that would be a good comparison.
 

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Well, I don't want to be one of those guys who just says "He**, that'll never work." without anything that truely convinces me of that. And, anything that has 300 guys raveing about it just can't be ignored out of hand. However, I also realize that 300 out of all the guys on this site is not a large sample (although I'm sure there are far more guys around the country doing it than just you guys).

I think one thing out of all that's been said really interests me about this. That is the "run flat" aspect. I don't really care about getting 20,000 miles out of a tire (although that would be nice), but maintaining the current handeling and getting a rear tire that wouldn't instantly come apart when it went flat has an appeal. Also better "wet" traction has a great deal of interest too.

If I ran all highways, I would probably do it without looking back, but I run tons a little 2 lane back roads and the handeling there is important to me. Enough so that as soon as the weather clears, and even though it only has 3,000 miles on it, the bike is headed over to get a full Traxxion make over.

I do appreciate your offer of a ride, but by the time I got from NH to Texas and back (and paid all those motel bills), I could have bought a spare rim and tried it for myself - LOL :p:p:p:p:p:p
Steve, I know, but the offer stands. And why only 300+ out of thousands? There are only a few of us with brass ones big enough to go to the edge and discover that the world really is round. It's well worth the change. It took me a year to try it, but now that I have I won't go back. It's awesome on highway or backroads and, to be honest, I was never comfortable on the MT above 115, but with the CT it's solid as a rock all the way up to 130. I'm glad you are researching this completely, it's the only wise thing to do. And, like you, the runflat idea was a big + for me as well. Thanks for the great questions and dialogue.
 

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NH1800,

I think you will find that most CT have about the same profile as the tire in the video. We just think of them as being flat. Take your time. The only bad thing about taking your time is when you do finally change over to the CT you will wish you would have done it when you first started looking into it.;)

John
 

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This Wing was on its sidestand, so it isn't leaned over very far. Nevertheless, look how much of the tread is sitting on the ground. A motorcycle tire would never have that much tread in contact with the road, regardless of the lean angle.


My memory's a little foggy on the specifics, but IIRC it was a runflat, and at the time was carrying only about 15 psi. This was at Prudhoe Bay, and he had aired it down for the gravel road. It handled well enough that after the rider had grown accustomed to riding on gravel, he managed to earn a performance award from one of Alaska's finest. :lol: First time I'd ever seen anyone get a ticket on the Dalton Hwy. Tagged at 71 in a 50. :eek:
 

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Discussion Starter · #20 ·
There are only a few of us with brass ones big enough to go to the edge and discover that the world really is round. It's well worth the change. It took me a year to try it, but now that I have I won't go back.
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Thanks for the great questions and dialogue.
Well, I hope the questions I have are good ones. I know you guys must get really sick of "proving" this idea over and over as each of us new guys comes along and questions it. But at least now you've got me curious about this.

I'm still thinking back to the 50's when I was a kid. About the only bikes we saw around here were big HD's (and a few Indians). Most were left over WWII surplus and I would swear I remember then having a squarer profile tire than the ones we use today. Of course, at that age, all I had to compare them to was bicycle tires and car tires (and the memory dims with age - LOL), but ........

Maybe that's all they could get (or afford) in those days, but my point is that I'm not sure that this is a new "revelation" or just the re-discovery of an old idea by a new generation of bikers.

I think I saw someone here who commented that the motorcycle tire industry was driven by racing and not by touring, so it would make sense that tires have evolved in that direction. But what works well on the track does not always work well on the street and visa-versa.

And, after a generation or two, all the old guys who could have answered a lot of these questions are not around any more. But it would be interesting to talk to one of those guys and see if my memories are really true.

Maybe a little more research on the web might turn up something.
 
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