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Discussion Starter #1
Regarding PSI, I settled on 37F/47R this past summer but I wanted to hear from all of you and what you prefer.


Mostly solo riding with some luggage at times.
 

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42/42
 

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I ride two-up and loaded most of the time so I run 42/48 all the time, but you could lower the rear for solo riding.
 

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36/42


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I have run 42/48 for 13 years but now I am tired of the hard ride and I am going to go back to the Factory recommend pressure to see what I have been missing. I can keep a close eye on the effects as I have a Smartire system that gives me absolute pressure, delta from cold and temperature. I noticed a change in temp going from ME880 to BT020 on the rear as the Bridgestone ran hotter for the same pressure and loading over the Metzeler.
 

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Ok John the race is on - sort of

I am also running a Smartire system also

https://www.vulcantire.com/smartire_mc_sys.htm

(no longer made) and the thing will just not die - so lets see how long they last!!

Mine must be around 15 or 16 years old. Was on my 02' LT and transferred is to my 2009 LT.

As for tires now that my LT has a Hannigan SP2 sidecar bolted on to it am now running a Shinko SR741 130/70-17 Rear Tire 87-4468 on the front.

This is a rear tire but fits the LT rim perfectly and requires no fender modifications and boy does this tire have some meat on it.
This is what other LT sidecars and trikes are running and at $66 a tire from Amazon - not a bad deal. Got about 700 miles on the current tire and no signs of wear and that's no bad for a sidecar rig which never leans.

Oh yea run the tire at 48 lbs . . .
 
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I have run 42/48 for 13 years but now I am tired of the hard ride and I am going to go back to the Factory recommend pressure to see what I have been missing. I can keep a close eye on the effects as I have a Smartire system that gives me absolute pressure, delta from cold and temperature. I noticed a change in temp going from ME880 to BT020 on the rear as the Bridgestone ran hotter for the same pressure and loading over the Metzeler.
I also thought the BT seemed to run warmer than the ME, but I never tried to measure the temp so I wasn't sure if it was just my imagination. And it's max inflation pressure is two psi less so can't go above 48. I probably should try to measure the temp with my IR thermometer, but then unless you have two identical bikes riding side by side, it would be hard to make meaningful comparisons given the number of variables.

42/48 has worked well for me riding two-up and loaded, but is a touch harsh for solo riding. I would think 36/42 would work well and I think is close to the factory recommendations. Since I ride dual as much or more than solo, I just leave pressures on the high side. If I was to take a long solo ride, I think I would back off a few psi.
 

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Ok John the race is on - sort of

I am also running a Smartire system also

https://www.vulcantire.com/smartire_mc_sys.htm

(no longer made) and the thing will just not die - so lets see how long they last!!

Mine must be around 15 or 16 years old. Was on my 02' LT and transferred is to my 2009 LT.

As for tires now that my LT has a Hannigan SP2 sidecar bolted on to it am now running a Shinko SR741 130/70-17 Rear Tire 87-4468 on the front.
I snagged about 9 Smartire units off ebay a while back and unbeknownst to either myself or the seller these read out in PSI but have temp in Celsius. This is established by the receiver not the transmitters so I have lots of new senders.

Now the real question since this is designed "rear" tire did you have it mounted backwards? If not then it may slip on the rim under hard braking. It is all about the bead design since rear tires are designed to grip on acceleration forces and front tire are designed to grip under braking forces.
 
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Discussion Starter #10
That sounds good.

Thanks everyone!
 

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The manual has 36.3 PSI F (2.5 bar) for front under all conditions and 42.1 PSI R(2.9 bar) for solo and two up and goes to 46.4 PSI R(3.2 bar) for two up+luggage. So 37F/47R is pretty much spot on with the factory recommendations.
 
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Yesterday a went and did a riders skills course at the local race track. The night before I checked my tyre pressures and inflated them to 36/42
When I got to the track we were asked to check our pressures and take them to about 30 psi. I mentioned that I had mine to factory specs but the instructor pointed out that considering it was a very hot day, 35 deg C or roughly 95 deg F that it was probably better to let some air out because the track temp would be increasing the psi in your tyres, makes sense.
I guess the correct answer to the question might be, depends on the season and what you are doing. Cold weather, higher psi. Hot weather, lower psi.
 

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Yesterday a went and did a riders skills course at the local race track. The night before I checked my tyre pressures and inflated them to 36/42
When I got to the track we were asked to check our pressures and take them to about 30 psi. I mentioned that I had mine to factory specs but the instructor pointed out that considering it was a very hot day, 35 deg C or roughly 95 deg F that it was probably better to let some air out because the track temp would be increasing the psi in your tyres, makes sense.
I guess the correct answer to the question might be, depends on the season and what you are doing. Cold weather, higher psi. Hot weather, lower psi.
Your instructor is ill-informed. The tire and bike makers account for tire pressure increases due to tire heating during use. And you should not be adjusting pressure after you have ridden and heated up the tires. I understand wanting to warm up street tires a little more for track use, but the LT isn't a 400 lb race bike. Running high speeds on under inflated tires, especially on a hot day, is asking for trouble.

This is as bad as the MSF instructors who teach that counter steering magically quits working below some magic speed, typically 15-20 MPH.
 
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One can stop expansion somewhat by using nitrogen.......

We used it drag racing and often after a run I would quickly check it out in shutdown. Often that was a mid 190 mph run after a lengthy burnout. It was pretty consistent. More so than just air. A street tire will not be subjected to that type abuse.

street bike...I use plain old air. Car tires, the same.

Plus I might add. Its not so much the expansion difference in air and nitrogen but the contamination involved with using air. Moisture,oil,etc.

Yes, I am splitting hairs with these comments.....
 

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One can stop expansion somewhat by using nitrogen.......

We used it drag racing and often after a run I would quickly check it out in shutdown. Often that was a mid 190 mph run after a lengthy burnout. It was pretty consistent. More so than just air. A street tire will not be subjected to that type abuse.

street bike...I use plain old air. Car tires, the same.

Plus I might add. Its not so much the expansion difference in air and nitrogen but the contamination involved with using air. Moisture,oil,etc.

Yes, I am splitting hairs with these comments.....
If you look at the ideal gas law, you will see that the type of gas does not enter into the equation. Nitrogen and dry air will expand at the same rate with temp changes. The key here is "dry." Most compressed air contains water vapor which will undergo a phase change at certain key temps, namely 32 and 212 for us US folks and 0 and 100 for the rest of the world. This will muck up the ideal gas law relationship.

If you have access to dry air, then using Nitrogen has no benefit over air from an expansion with temperature perspective. You still have the very slight advantage of a little less permeability through the rubber, but that is a long-term issue, not a short-term expansion with temp issue.
Ideal Gas
 
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So, that SmartTire System looks great. How is the metal clamp used to secure the sensors?


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So, that SmartTire System looks great. How is the metal clamp used to secure the sensors?


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It goes through the sensor and around the drop well of the wheel. Install during a tire change and leave in place for at least 13 years (how long mine have lasted and still going).
 

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Not a bad idea at all.....

I used a tire monitoring system for my pull vehicle on my motorhome....

It saved me couple times from a mess......

Then I added it to the motorhome itself.....
 
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