Thank you, TPMS

[Disco]

It was chilly this morning at 0620, but not as cold as it has been at times during the last month.  So, when the TPMS warning light came on I had a pretty good idea I had a problem.  I have both front and rear sensors set at 40 lbs and the warnings begin at 10% low.  My front was fine, but the rear showed 35 lbs.  It warmed up enough to gain a few pounds on the ride in, but when I got to work, I checked the tire, and sure enough I have a nail or screw smack dab in the center of the tread.  It hadn't lost any more pressure when I left this afternoon, but it was more than 20 degrees warmer.  Gave it a booster shot this evening when I got home and I'm curious to see what it will be morning. 

Sucks that it's there.  Nice that I knew about it before it caused a problem. 

I guess my upcoming final drive service just got a bit more involved.  Hopefully, I'll be saying, "Thank you, Pocket Plugger!"...

[Westsider]

Sucks that it's there.  Nice that I knew about it before it caused a problem.  


 


Like that TPMS,,, I dont have one , but I like them. Maybe next tire change.

[BnB Tom]

Phew!

  Had me worried for a minute.

I thought TPMS was TEXAS PUBLIC MONITORING SYSTEM . .  and you're personal space had just been invaded!!!   

[HayHauler]

Gonna put one on the Valk.  The one on the Wing has worried me when the temps are low.  I am still amazed how much pressure increases as you ride.  I have had the rear tire go from 36 to 45 while riding and I didn't think tire pressure would swing that much.

Glad you found the problem. 

Was that in your new tire??!!

Hay 
Jimmyt

[hotglue #43]

I wonder if TPMS will work with Ride On in the tires? ???

[Houdini]

I wonder if TPMS will work with Ride On in the tires?

I was told to not put on the TPMS because I had the Ride-On in already.  I stuck with Ride-On because I'm a nail magnet.

[5_19]

Good rule of tumb !

Check tire pressure cold and it should go up about 10% after 30 minutes. Goes up less to much pressure, goes up more not enough

[hotglue #43]

That makes sense TJ....  not enough initial pressure and the tire gets hotter raising the pressure higher than it would if the correct pressure is in the tire.

[HayHauler]

Would it not raise it to the same pressure?  Just the pressure difference would be greater?
 Starting pressure       Ending pressure
40                            44
35                            44
30                            44

The lower starting pressure would generate more heat, but wouldn't it equalize as the pressure reached the max?  As the pressure rose, would the tire stop generating heat?

I think I am now confused.....

Hay 
Jimmyt

[Valkpilot]

Would it not raise it to the same pressure?  Just the pressure difference would be greater?
 Starting pressure       Ending pressure
40                            44
35                            44
30                            44

The lower starting pressure would generate more heat, but wouldn't it equalize as the pressure reached the max?  As the pressure rose, would the tire stop generating heat?

I think I am now confused.....

Hay 
Jimmyt

The tire will always generate heat due to friction with the road surface.  The question is will the heat generation translate to constantly increasing pressure. If the initial pressure is too low, the air can't expand enough to generate sufficient pressure to properly fill the tire.  When this happens, the tread and sidewall flexes more, further increasing the heat load without any meaningful pressure increase.  In extreme cases, the sidewall will explode from too much flexing and heat.

Pressure changes 0.1 psi for each degree of temp change (Fahrenheit.)  So 1 psi of change means the internal temp of the tire has changed 10 degrees.  If your cold-tire was 2 psi low because of a 20 degree drop in temperature from when it was last filled cold, it would regain that original pressure as soon as the internal temp of the tire came up 20° F.  That doesn't correlate to optimum operating pressure though, since cooler ambient temp mean cooler tire temps, so you might not experience the same pressure increase throughout your ride as you would at the warmer ambient temp when you filled your tire.

In your  earlier example, to go from 36 to 45 psi, the temp inside your tire increased 90° F, which seems like an awful lot.  If you started at 36 psi at an ambient cold temp of 60° F, the internal temp of the tire would have been 126° F when you got to 45 psi. 

Sorry, TJ, but i don't necessarily agree with your rule of thumb because different tires (darkside vs a knobby, as an extreme example) will heat at very different rates, so time as a criteria for checking the increase may not be reliable.

I'm running Ride-On in both bikes and both have TPMS systems.  I've got this system on both: http://www.bigbikeparts.com/Inventory/Navision/13-315A?catalogNo= and haven't experienced problems in the 18 months or so I've had them.

[HayHauler]

"If the initial pressure is too low, the air can't expand enough to generate sufficient pressure to properly fill the tire.  When this happens, the tread and sidewall flexes more, further increasing the heat load without any meaningful pressure increase.  In extreme cases, the sidewall will explode from too much flexing and heat."

Well, that splains it.
Thanks for learnin me something today. 

Hay 
Jimmyt

[Disco]

I'm running Ride-On in both bikes and both have TPMS systems.

I believe there is an important distinction when considering TPMS + in-tire sealants.  Your combination of Ride-On + Big Bike Parts TPMS has the sensors outside the rim on top of the valve stem.  I opted to mount the sensors for my Doran 360M on the bottom of the included metal valve stems inside the tires and they do not recommend commingling the sensors with any in-tire sealant. 

[Valkpilot]

I'm running Ride-On in both bikes and both have TPMS systems.

I believe there is an important distinction when considering TPMS + in-tire sealants.  Your combination of Ride-On + Big Bike Parts TPMS has the sensors outside the rim on top of the valve stem.  I opted to mount the sensors for my Doran 360M on the bottom of the included metal valve stems inside the tires and they do not recommend commingling the sensors with any in-tire sealant. 

Absolutely.  I should have made the distinction.  Further, aren't there some inside-the-tire sensors that are compatible with Ride-On, or am I thinking of DynaBeads?

[5_19]

VP I agree with you. My rule is way to simple. However it's what I came up with after talking to a very passionate Michelin motorcycle riding tire engineer and their tires. Many many factors play into this. Tire pressure should increase after the tire warms up and for my application with a 80-90 ambient it's should be about 10%.

Great tire thread Disco! Disclaimer please check with your tire manufacturer for recommendation. LOL

[Disco]

...aren't there some inside-the-tire sensors that are compatible with Ride-On, or am I thinking of DynaBeads?

I'm not saying they don't exist, but I'm not aware of any in-tire sensor TPMS system whose manufacturer approves of in-tire sealants.  I suspect that they wouldn't even recommend the use of Dyna Beads with in-tire sensors, but I've had no problem with that combo for almost 100,000 tire miles.   

[Disco]

The nail or screw had slung out, but the hole was leaking, albeit very slowly.  Hole reamed, mushroom plug inserted, 3/16" long remnant of plug outside the tire cut off, aired up to 40 psi.  Now, we wait...

[Red Diamond]

The nail or screw had slung out, but the hole was leaking, albeit very slowly.  Hole reamed, mushroom plug inserted, 3/16" long remnant of plug outside the tire cut off, aired up to 40 psi.  Now, we wait...

Dave do you run the same type TPMS in the front and rear tire? I run M/C tires front and rear, was wondering what all is needed to install the system.

[HayHauler]

RD, it's called a Doran unit that installs either internal or external and you can program the pressures different for front and back.  I have one on thwing and really like it.  I an going to also put one on the Valk.  I like knowing the pressure of both tires at a glance.  I bought the 2 tire unit that comes with 2 sensors, straight and 90 degree metal valve stems, control unit, and a remote LED light.
Can you tell that I like it?

Hay
Jimmyt

[HayHauler]

http://www.doranmfg.com/motorcycle-tire-pressure-monitoring-systems.htm

This is it.

Hay
Jimmyt

[Disco]

Dave do you run the same type TPMS in the front and rear tire?

Yes, it's the same one HH is running.  I originally had it on the 'wing and pulled everything but the stems and sensors from it before it went to salvage.  I purchased replacement stems and sensors and put it on the Valkyrie.  I like having the sensors inside the tire, threadlocked to the stem, but it sure is a PITA when the batteries wear out and they have to be replaced.  The sensors, that is.  The batteries are not replaceable. 

To me, it's still worth whatever inconvenience to install/maintain a TPMS in order to know what's going on at the push of a button.   

[HayHauler]

I concur.    Small price to pay for piece of mind.

Hay 
Jimmyt

[Red Diamond]

Thanks, DD and HH, I'll look into the system. Hope they work with those 2 sets of metal valve stems I won at Inzane.

[HayHauler]

No need, they come with 2 sets.

Hay 8
Jimmyt