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How many people really know what speed their tyre is rated to or where to even look on the tyre, I asked a dealer about the ones I put on my 1100XX Michelin Pilot 4's which are rated to 168MPH well the bike is supposed to do 175MPH flat chat.
Was told "Well they have to put something on them!".

So in a court of law you would probably not be able to sue the companies that made the tyre if you exceeded their speed rating only if it was proven there was a serious manufacturing flaw that was missed or design flaw that made the tyre unsafe.
 

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Cars like the Bugatti Veyron SS, Chiron, and some of the creations by John Hennessey and Koenigsegg actually exceed the top speeds of the fastest tyres available on the planet. In their case, the tyres simply wear at an extremely alarming rate.

Meanwhile, Goodyear's G159 tyre was meant for regional trucks that would never exceed 65 mph. They were happy to sell them to RV manufacturers. Unfortunately, unlike the aforementioned hypercar tyres, exceeding 65 in a vehicle equipped with G159s can and repeatedly have resulted in fatalities.

So what does exceeding your speed rating do? Well it can widely vary between not much and an unfortunate crash.
 

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I'm not sure why anyone would want to go over about 80 mph or so anyway. There are so many things that can cause you to wreck. A public highway can have a pothole, crack, car part, animal crossing, or cops. Even Isle of Man riders get killed and they're on bikes that are specially built and carefully prepped for racing. On a regular race course, one would be safer and more protected from obstacles, but are you sure your bike is in perfect condition for real high speed?

Having done a highside while going 70 mph on a freeway, I sure don't want to know what would happen at 105. :surprise:

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I'm with you Ron but as far as why would anyone want to go that fast, sometimes you get the wild hair or itch that just needs to be scratched. No, it isn't safe or smart but I think that's the reason. I also don't think doing these not too wise things once in awhile won't cause a major problem but doing it all the time most likely will.

I searched the speed rating on my factory tires when people started raving about another brand and began questioning whether they had looked that little number up on that tire they all like so much. Probably not.

It just isn't something most think about. But they really should if you consider there isn't much leeway as far as load capacity goes in the first place on most bikes. So had higher speeds and you got a witches brew disaster potential.

The OP is the only one that can answer so, why are you asking SiR CANT?(no disrespect intended there, just one of those wild hair things):surprise::grin::angel:
 

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i normally push bikes as hard as they go. i grew up offroad racing so it's just my default riding style. i know most cringe at 100 mph but to me its slower than a turtle.

That being said if my machine truly can't support a speed i am not dumb enough to do it. After a lot more research and contacting bridgestone directly the TW52 is for sure an S rated tire. It doesn't seem like the best tire in the world though so I probably will experiment with other ones.

D606 seem like everyones go to tires but they seem to fall apart on roadways 70+ pretty quick and not be too good in the sand.

Starcross 5 Soft seem to be great in the sand but fall apart quicker on pavement. They make a full range of tires but none cover both pavement and sand.

Anakee Wild seem to be a true 50/50 that's decent in sand and get 3000-5000 miles on pavement. I am a little skeptical about their mud/sand performance, but probably will still try the tire. Everyone says it's an incredibly loud and annoying tire.

I have a fully offroad direct path for my work commute so I can ride about 90 offroad 10 onroad if I really wanted.

All different things to think about. I probably will keep speed down on my road riding on my dual sport simply just to spare my tires, but it's quite a bit against my nature. Even in my car I just stomp and get where I'm going. I am a very polite and safe driver that being said. I always allow excessive following distance and slow it down in areas people can be around. Pretty much all woods roads and open highways where I live. The avg driver does 15-20mph speeding here. Going the speed limit actually is more hazardous here because so many idiots do not give following distance and try to pass dangerously. Pulling over normally isnt even an option. Idk...

Anyways back to the topic. Anybody got tire recommendations for a BRP/thumper?
 

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I'm not sure why anyone would want to go over about 80 mph or so anyway. There are so many things that can cause you to wreck. A public highway can have a pothole, crack, car part, animal crossing, or cops. Even Isle of Man riders get killed and they're on bikes that are specially built and carefully prepped for racing. On a regular race course, one would be safer and more protected from obstacles, but are you sure your bike is in perfect condition for real high speed?

Having done a highside while going 70 mph on a freeway, I sure don't want to know what would happen at 105. :surprise:

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80 is just the flow of traffic in Wisconsin and Illinois when there isn't congestion. :surprise: I've also taken a couple of my bikes to the ton a few times when I found myself on a big wide highway with no other cars around for a decent distance.

The Isle of Man TT is a crazy race. Take a century old race on roads that haven't gotten much wider since that past century, add about a million obstacles (walls, houses, people, etc) and modern bikes that can basically cruise at 200+ mph. It's no wonder why an average of three people die each year. Yet, I still wish to spectate one of the races one day before it inevitably gets axed for all the deaths that occur.
 

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It just isn't something most think about. But they really should if you consider there isn't much leeway as far as load capacity goes in the first place on most bikes. So had higher speeds and you got a witches brew disaster potential.

The OP is the only one that can answer so, why are you asking SiR CANT?(no disrespect intended there, just one of those wild hair things):surprise::grin::angel:
Speaking of load. I way 20 lbs more than what my WR250R is rated at and by the time I have a big back pack of stuff to go away for the weekend, I'm exceeding it possibly by 50 lbs. My tires are rated for it, but the motorcycle isn't.

How much extra risk am I adding? (and how light what I have to be to use the 2nd passenger pegs! LOL :smile_big: )

Mercedes saying that going faster than the tires are rated for could either mean quick wear or something dangerous - that 2nd part, I'd have to look into a lot before doing...Well the 1 time I did 100-110 MPH to keep up with California traffic...I hope to never do that again so...
 

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How many people really know what speed their tyre is rated to or where to even look on the tyre, I asked a dealer about the ones I put on my 1100XX Michelin Pilot 4's which are rated to 168MPH well the bike is supposed to do 175MPH flat chat.
Was told "Well they have to put something on them!".

So in a court of law you would probably not be able to sue the companies that made the tyre if you exceeded their speed rating only if it was proven there was a serious manufacturing flaw that was missed or design flaw that made the tyre unsafe.
In the early days of the then new-ish 'Z' rated steel belted tires... They were said to be rated for 150 + MPH.
I do believe I remember claims of up to 200 MPH for Z rated tires at one time. ?
Seems like they've settled on 168 MPH now cause.... "Well they have to put something on them!"
 

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80 is just the flow of traffic in Wisconsin and Illinois when there isn't congestion. :surprise: I've also taken a couple of my bikes to the ton a few times when I found myself on a big wide highway with no other cars around for a decent distance.

The Isle of Man TT is a crazy race. Take a century old race on roads that haven't gotten much wider since that past century, add about a million obstacles (walls, houses, people, etc) and modern bikes that can basically cruise at 200+ mph. It's no wonder why an average of three people die each year. Yet, I still wish to spectate one of the races one day before it inevitably gets axed for all the deaths that occur.
The TT races in June, are usually booked up well in advance. An option is to go to the Manx races in September.

UK
 

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Speaking of load. I way 20 lbs more than what my WR250R is rated at and by the time I have a big back pack of stuff to go away for the weekend, I'm exceeding it possibly by 50 lbs. My tires are rated for it, but the motorcycle isn't.

How much extra risk am I adding? (and how light what I have to be to use the 2nd passenger pegs! LOL :smile_big: )

Mercedes saying that going faster than the tires are rated for could either mean quick wear or something dangerous - that 2nd part, I'd have to look into a lot before doing...Well the 1 time I did 100-110 MPH to keep up with California traffic...I hope to never do that again so...
Pure guess on my part but probably not much as the legal eagles are more like whiney chickens. But it does give you incentive for weight reduction somewhere.
 

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80 MPH will not do the job around here if you want to use the left lane on the interstate, despite speed limits of 65-75 depending on the area the normal cruise speed is usually around 85-90 in the left lane unless traffic is tied up. And this is in the east, when I was out west, crossing the plains and into South Dakota the cruising speeds were even higher, pushing 100 and it was hot too which makes it harder on the tires.
I will admit that occasionally I have decided on a lonely road to see just how fast my bike will go, I can neither confirm nor deny hitting the 125 mph speed governer on both the 08 and the 16.

My bikes present a special challenge for back tires too...Visions are heavy and have the back wheel very enclosed and the engine heat ends up there, my TPMS gives me temperatures too and I have seen over 120F in that wheel area when the outside air was 95F. Under these condtions the 40-41 pound pressure exceeds 50 PSi..scary but that is how it is. I ride long distance regularly so I need tires that can take 100 mph for 24 hours with only a brief stop every 200 miles in hot weather without having to worry about them, not to mention working at interstate speeds in all conditions from pouring rain to well below freezing temps. Some tires do not cut it under these condtions, a few tire brands have developed a reputation in that small community for NOT working on Visions despite being fine on other bikes, blowing out unexpectedly and hurting people, while others wear very quickly under the heat and load. Others work very well.
 

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As the tire flexes locally while contacting the road surface, then returns to it's unloaded shape the flexing generates internal heat. Greater load means a greater amplitude of flex. Higher speed means more cycles per second, and so more heat generated.

My understanding is that tire speed rating is mainly a measure of the tires ability to dissipate the heat of operation. The speed is that which can be sustained at the rated load, without overheating the tire, if it is inflated to the correct pressure. There is, I believe, sufficient factor of safety built into tires such that you can run overspeed or overload for a limited amount of time. But doing that on a hot road, for hours, is asking for trouble. If I was running overload, I'd want to increase tire pressure a bit, within the tire's limit, provided this didn't adversely effect handling, and I'd try to reduce speed by an amount proportionate to the overload.

Testing of the tires is done under lab conditions, and doesn't take into account the handling nasty sharp edged potholes and road debris that are out in the real world.

Under inflation is the most common abuse that we subject our tires to, and causes overflexing, internal heating and degradation of the rubber. Valves leak, and no seal or membrane is perfectly airtight. Check your tires often. Over inflation can cause tread separation which might not show up immediately, but might result in a later catastrophic failure. Blowouts are thankfully, a lot less common with modern tires.
 

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My experience with exceeding speed ratings isn’t on 2 wheels but with something of the cage variety. I was a tech working for a Lincoln/Mercury dealer and got in a Cougar XR7 that the owner complained about a vibration on the freeway. First I inspected all suspension components, U joints and bearings... all is well. Take the car on a test drive and get up to 70 (in a 55) and still smooth as silk. Give the car back unable to verify complaint.

A week later the car is back same issue. Once again I cannot duplicate so I suggest a ride along. The owner agrees. I drive and he gets to tell me what he is feeling. Up to 70 again and no issue. Then the owner states the problem doesn’t start happening till over 85! The stock tires for his car were rated for safe operation below 80 mph (p or s rated). Needless to say we refused to “repair” his car and suggested to him to keep the speed down closer to the speed limit.
 

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Another issue that can appear: The tyre swells and makes contact with a frame part. The rear tyre on my XS1100 is very close to the swing arm. There is little room for sideways expansion.
Barry Sheen had a rear tyre explode at Daytona due to tyre expansion, and then rubbing on a frame part. He got off at 190 mph.

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How many people really know what speed their tyre is rated to or where to even look on the tyre,
Well I know I do, at least the approximate speed 150 mph. The only way I will reach that speed is if I accidently ride off a cliff. At that point whether or not my tires hold up won't be much of a concern :surprise: .
 

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If you are going to play the game, know the rules. Now I never paid attention to car tires but I certainly do to scooter tires. In most cases you only have 2. Not knowing could be hazardous to your health.
 

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I'm not sure why anyone would want to go over about 80 mph or so anyway. There are so many things that can cause you to wreck. A public highway can have a pothole, crack, car part, animal crossing, or cops...
DSCN2980Crop.jpg

All true, no question about it... but there's a certain seductiveness to see what lurks on the other side of the dial...
 
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