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Are 4mil heavy duty tubes a good idea or are they bad on roads at high speed etc. Some forums suggest they run hot on highways?
 

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The thick tube wall does generate heat at speed.

You shouldn't need to air down low enough to risk a pinch flat anyway - a bike this heavy I would go probably no lower than 15psi if I were riding in rough rocky terrain.
 

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heavy duty thick tubes might give a little less chance to have a flat but they are only for off road use. Not a good idea if you ride on paved roads and highways most of the time, as they will run hot at high speeds. Instead I put Slime or some similar anti puncture product on my tubes as suggested by the tires expert on: Understanding the Motorcycle Tube - T.J. Tennent — Motorcycle Podcasts Adventure Rider Radio & RAW
It's also adviced to have natural rubber tubes over synthetic-butyl for mostly on road use. And Bias-ply front or Radials rear tubes for the respective types of tires on the AT
 

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After getting three flats on a KLR 650, for no apparent reason I switched to HD tubes. Didn’t have any more flats.

I never noticed any issues at speed, although it was a KLR650 so speed is a relative term. I should say I never noticed any issues and I rode a lot of highway speeds.

I just put HD tubes in my AT and kept the originals as spares. Theoretically speaking, HD tubes are heavier therefore should heat up more and have a gyroscopic effect, but realistically how much heavier are they really?

I think the performance difference on the street will not be noticeable. Someone correct me if I’m wrong.
 

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After getting three flats on a KLR 650, for no apparent reason I switched to HD tubes. Didn’t have any more flats.

I never noticed any issues at speed, although it was a KLR650 so speed is a relative term. I should say I never noticed any issues and I rode a lot of highway speeds.

I just put HD tubes in my AT and kept the originals as spares. Theoretically speaking, HD tubes are heavier therefore should heat up more and have a gyroscopic effect, but realistically how much heavier are they really?

I think the performance difference on the street will not be noticeable. Someone correct me if I’m wrong.
Just put in HD tubes yesterday. The gyroscopic effect is horrible. The bike is like a tanker instead of a motorboat. Will change it back asap.
 

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Are 4mil heavy duty tubes a good idea or are they bad on roads at high speed etc. Some forums suggest they run hot on highways?
From some information presented on another platform the heavy duty tubes are primarily for off road use as the thinner tubes generate less heat at highway speeds. That said, the comments mention the heat build up by heavy duty tubes is not a serious issue until travelling at speeds near or over 100mph. 60 mph in Death Valley at mid summer may be an exception. Since we don't generally change tubes when leaving the highway and heading off road, consider where most of the riding will occur and choose accordingly.
 

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Ok,
Let's discuss this Heat thing that is supposed to happen when using an HD tube. Why and how, does this type of tube generate any more heat, than a standard tube does or would? And, while I'm by far, no expert on any of this, I would think that the folks that produce any style of HD tube, would advise, on any packaging of their products that, THIS TUBE IS TO BE USED FOR OFF ROAD ONLY, as the use of it, MAY generate internal heat. And, even IF it generated more heat, then why would you put an OFF ROAD RIDER in more jeopardy than a street rider?

Is or are there, any such warnings on any packaging or, on the tube(s) themselves? And, let's say there IS more heat. Just HOW MUCH heat is generated vs a regular tube? I mean, does anyone have direct evidence, in a controlled set of testing operations, that shows that,

1. A factory tube, on a given motorcycle, set at a given pressure, generates X amount of heat, at a given speed, as shown on an infrared heat detector gun or any other form of measurement.
2. Running the same motorcycle, with the same rider, in the same condition(s) or test track, is generating Y heat, shown on the same test equipment.

If, IF, there's a difference in the amount of X vs Y heat, how much? And, if there is an actual rise in temps on an HD tube, how long does it take to actually generate that heat, a few feet, a few miles, 20 miles, 50 miles and, at what speed(s)?

And one more question. If there is evidence of higher heat operations, could that heat be critical or DEADLY? One of you mentioned the "Gyroscopic" effect of an HD tube. Well, tires and wheels are BUILT IN gyroscopes. The faster you ride, the more gyroscopic effect they have on the bike itself. Ever spin a bicycle wheel in your hand by holding it by the axle? When that bicycle wheel is not spinning, and you're holding it by one side of the axle, it will tip over.

When you begin to spin it, you can actually hole it by one side of the axle and it won't tip. The faster you spin it, while holding it, the more stable it is and the tougher it is to try and tip that wheel sideways. Spinning objects, like discs and wheels, don't like to be tipped. They like to stay in the rotating axis they're spinning in.

Now, if a tire was installed with an HD tube and it now SHAKES at speeds, well, that's a given, IT'S OUT OF BALANCE and needs balancing.
Scott
 

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One of you mentioned the "Gyroscopic" effect of an HD tube. Well, tires and wheels are BUILT IN gyroscopes. The faster you ride, the more gyroscopic effect they have on the bike itself. Ever spin a bicycle wheel in your hand by holding it by the axle? When that bicycle wheel is not spinning, and you're holding it by one side of the axle, it will tip over.

When you begin to spin it, you can actually hole it by one side of the axle and it won't tip. The faster you spin it, while holding it, the more stable it is and the tougher it is to try and tip that wheel sideways. Spinning objects, like discs and wheels, don't like to be tipped. They like to stay in the rotating axis they're spinning in.
Considering the total mass of a motorcycle wheel with tire, tube and balance weights installed I don't think there would be much change in gyroscopic force between heavy duty tubes and thinner tubes. As rotational speed increases so do the gyroscope forces. When a force is applied to a rotating wheel, the wheel responds as if that force was applied to the wheel at a point 90 degrees from the application point in the direction of rotation. Motorcycle stability results from the front and rear wheel working with and against each other. Understanding it can be a real mind bender if in the wrong mood.
 

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RE HD tube heat: I am wondering due to maybe more rubber mass (??) in HD tubes, they don't "get hotter", but rather, retain the heat longer? Is that what is really going on? That is, more enthalpy?
 

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RE HD tube heat: I am wondering due to maybe more rubber mass (??) in HD tubes, they don't "get hotter", but rather, retain the heat longer? Is that what is really going on? That is, more enthalpy?
Enthalpy
Enthalpy is a property of a thermodynamic system, defined as the sum of the system's internal energy and the product of its pressure and volume, H = U + pV. It is a convenient state function standardly used in many measurements in chemical, biological, and physical systems at a constant pressure. The pressure–volume term expresses the work required to establish the system's physical dimensions, i.e. to make room for it by displacing its surroundings. As a state function, enthalpy depends only on the final configuration of internal energy, pressure, and volume, not on the path taken to achieve it.

Ok, I had to take a lot of pills and make an appointment with a therapist after reading, or trying to read this.
Scott
 

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The thick tube wall does generate heat at speed.

You shouldn't need to air down low enough to risk a pinch flat anyway - a bike this heavy I would go probably no lower than 15psi if I were riding in rough rocky terrain.
I wouldn’t go below 25psi with TKC80 on the front. I’ve three bends in the front rim to back up that statement.
No less than 20psi with Mitas E-10 Dakar up front.
 

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heavy duty thick tubes might give a little less chance to have a flat but they are only for off road use. Not a good idea if you ride on paved roads and highways most of the time, as they will run hot at high speeds. Instead I put Slime or some similar anti puncture product on my tubes as suggested by the tires expert on: Understanding the Motorcycle Tube - T.J. Tennent — Motorcycle Podcasts Adventure Rider Radio & RAW
It's also adviced to have natural rubber tubes over synthetic-butyl for mostly on road use. And Bias-ply front or Radials rear tubes for the respective types of tires on the AT
HD tubes are not restricted to off road. I use HD (not UHD) tubes for all conditions, all tyres. Never a problem even 35C with knobs full day on pavement. I rarely exceed 120 Kmh though. Sykik TPMS monitors pressure and temperature.
Never used Slime and never will. Helped repair trail side flats where it didn’t work. Total gooey mess.
Agree. Synthetic tubes can shred if run near flat. Always carry a spare tube.
 

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Just put in HD tubes yesterday. The gyroscopic effect is horrible. The bike is like a tanker instead of a motorboat. Will change it back asap.
Surprised you noticed a difference. MOTOZ or Mitas Dakar tyres are twice the weight of OE Dunlop’s and I’m running HD tubes too. Feels totally OK for how I ride on and off road.
 

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Ok,
Let's discuss this Heat thing that is supposed to happen when using an HD tube. Why and how, does this type of tube generate any more heat, than a standard tube does or would? And, while I'm by far, no expert on any of this, I would think that the folks that produce any style of HD tube, would advise, on any packaging of their products that, THIS TUBE IS TO BE USED FOR OFF ROAD ONLY, as the use of it, MAY generate internal heat. And, even IF it generated more heat, then why would you put an OFF ROAD RIDER in more jeopardy than a street rider?
Off-Road riders are not known for traveling off-road at 80+ MPH for extended periods of time, so heat and expansion won't be as big of a deal. But unless the tube is marked NHS (Not for Highway Service) as some tires, tubes, and Bib-Mousse are, then it should be fine.
 

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Off-Road riders are not known for traveling off-road at 80+ MPH for extended periods of time, so heat and expansion won't be as big of a deal. But unless the tube is marked NHS (Not for Highway Service) as some tires, tubes, and Bib-Mousse are, then it should be fine.
It never occurred to me some motorcycle tubes would be designated NHS. I have learned more about tubes from this forum in the last two months than riding for the previous 4+ decades. Hopefully the guy behind the parts counter knows more than me when I need to replace tires and tubes.
 

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It never occurred to me some motorcycle tubes would be designated NHS. I have learned more about tubes from this forum in the last two months than riding for the previous 4+ decades. Hopefully the guy behind the parts counter knows more than me when I need to replace tires and tubes.
I have heard that the NHS marking is primarily for the USA market. I am not sure how prevalent it is outside the USA or how common it is even in the USA. Most tubes are not marked NHS, but Pirelli for example has some tube applications marked NHS.

Bib-Mousse is marked NHS for off-road use only, Pirelli Diablo Superbike Slicks are also marked NHS.
 

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Off-Road riders are not known for traveling off-road at 80+ MPH for extended periods of time, so heat and expansion won't be as big of a deal. But unless the tube is marked NHS (Not for Highway Service) as some tires, tubes, and Bib-Mousse are, then it should be fine.
I thank you for your explanation and answer. You stated that off road riders are not known for 80+ mph stuff, correct? What about the DAKAR type riders? Those boys do some seriously fast riding and, over some UGLY terrain at those serious speeds. Wonder what kind of tubes they're running? They SURELY don't want flats.
Scott
 

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Dakar is a poor example for a couple of reasons.

Vehicles in the T3, T4, T5 class which includes light prototypes, UTV's and trucks are limited to 81mph. Motorcycles have been speed limited in other events and Dakar is looking at placing a similar 81mph speed limit on them due to the dangers and recent loss of life.

Also, I know at least for the KTM racing team, which knows a thing or two about competing in Dakar, they use Michellin tires and Desert Mousse (not a dessert ), which are of course NHS.




The main thing that HD and UHD tubes will provide the rider is a thicker carcass and some prevention against pinch flats, which really aren't so much a thing for road riding as they are off-road.

But as I mentioned in my previous post, unless they are marked NHS, they should be fine for road use at highway speeds.

I think the biggest negative of a heavier tube is going to be the unsprung weight and gyroscopic effect mentioned and they are harder to change in the field, particularly UHD's.

But unless the tube is marked NHS, it is up to the rider whether or not they want to use them. I know of no reason they wouldn't br otherwise just fine on and off road.






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When I experienced a flat from the stock front tube failing all the dealer had was a "heavy duty" tube so that's what I got. If there was any difference in handling or turn-in I never noticed it. The original tube at 3K became abraded from roughness inside the (original) tire and then failed. My 2020 AT only has a few hundred miles but whenever the tires wear out and I change them I think I'll go with premium (Perelli maybe) 4mm tubes and carry the lighter weight originals for spares. I'll also carefully feel the inside of whatever tires for any roughness.
 

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When I experienced a flat from the stock front tube failing all the dealer had was a "heavy duty" tube so that's what I got. If there was any difference in handling or turn-in I never noticed it. The original tube at 3K became abraded from roughness inside the (original) tire and then failed. My 2020 AT only has a few hundred miles but whenever the tires wear out and I change them I think I'll go with premium (Perelli maybe) 4mm tubes and carry the lighter weight originals for spares. I'll also carefully feel the inside of whatever tires for any roughness.
When the rear tubeless tire on my Triumph picked up a needle I put a tube in it I put a tube in and ran it for the rest of its life. The tire was just 2 months old when this happened. At that time the tubeless tires had a rough interior surface and the person I was buying the tube from recommended a heavy duty tube. His concerned a thin wall tube might not tolerate the rough surface well. It worked for the other two rear tires after that on the Triumph. Luck of the draw I guess, almost every new tire on the back of the Triumph picked up a screw or small nail within a few weeks of being installed. For several riding seasons I was the only one in my group of friends experiencing punctures. There are tubes specific to radial tires so that may be the best path for the radial rear. For the front the bike comes with a bias ply tire. Check the inside of the tire and go from there.
 
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