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Premium Member
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Discussion Starter #1
OK, I invested in not one but two roadgear digital air pressure gauges based on advice in the threads.

One thing I discovered was the $50 gauge I had been using wasn't accurate--when it read 42 lbs on my front tire, both of the roadgears showed 38.

It did, however, raise a question.

There's been plenty of discussion on "how long should I let the bike sit before I can consider the tires to be at 'cold' to measure air pressure?" and even "if I have to ride five miles to the nearest gas station with an air pump, how much should I compensate...and if I check the tires in the morning when it's 73 degrees, how different will it be at noon when it's 92 degrees outside, and should I adjust tire pressure?"

So here's my potentially dumbass question of the evening...

If the ol' LT is on the center stand, and I am checking the front tire pressure, would it make a difference in the pressure reading if the front tire were DOWN vs. IN THE AIR?

Should tire pressure be checked with the tires under load, in other words? If so, does that mean we should be checking with the bikes on the side stand (and to take that even further into the ridiculous, should we find someone who weighs about what we do to sit on it as we do. or better yet, have someone else check air pressure when WE sit on the bike, balanced upright, with just enough toe pressure from both feet down to keep it upright?


For the sake of science, I tested the front tire air pressure on the center stand with the tire under load (tire down) and then with weight on the back, lifting the front wheel in the air, and the gauge which reads in .5 lb increments showed zero difference. And knowing who I am posting this to, I repeated it five times with the same result.

Reason I ask is this...I had metzeler me880's with about 1,000 miles on them, took a 500 mile trek to southern TX a week and a half ago, and was heavy on the throttle. When I got down there, I had worn down the rear tire horribly (thank you, shitty overpriced tire gauge!!!) and picked up a small cut. $220 lesson learned about underinflation, hot asphalt and long miles.

So, emperors of engineering, what's the scoop? (and yes, I anticipate a few "what's it matter, just check before you ride and keep it at 42 front, 48 rear" responses)

Pete the tire destroyer
 

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1999 LTC
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Hey, Pete - not able to provide a definitive answer to your question(s), butt do have a suggestion. Get a SmarTire system installed and you can read what that unit does with temperature compensation.

Me? Even tho I have the system, I still check Toad's air pressures of a morning, using an Accuguage unit and without regard to whether on the centerstand or the sidestand. I think 'any' difference there, is gonna be minuscule and prolly not measurable by most tire pressure guages.

BTW - I haven't scientifically kept records, butt the SmarTire system usually shows anywhere from 3 to 5 psi differences from a cold tire standard basis setting to hot tires. More than that and it goes on alert. HTH a leetle.
 

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Discussion Starter #3
Ya' know, Dick, there are so many things I'd like to invest in...

my initial reaction is "gee, that smart tire system is about $200, that's too much right now" but had I done that two weeks ago, I wouldn't have been stranded in sh**hole Corpus Christi with a bald rear tire, begging dealerships to "pretty please order me a metzeler and install it" (BTW, it was a custom chopper shop, Kingpin Choppers, that was the ONLY place in 40 miles that would do it, every Harley, honda, kawi, and suzuki dealership refused--so much for a "brotherhood....") and spending MORE than $200 for the tire and mounting and balancing...

if only I weren't on Santa's naughty list, I could submit my "want it" list of...

-smart tire system
-remus exhaust
-replacement chip and timing remapping
-intercom system
-Ohlins suspension
-retrofitted electro-hydraulic centerstand
-gore-tex raingear
-DVD-Audio and MP3 12-disk changer switch-out
-heated vest, pants, gloves for cold weather
-top case and saddlebag liners
-HID upgrade for headlight

oh...and

the reigning Miss Asia as a passenger (would settle for any Miss Texas contender from the last 15 years)


does anyone know of a Sugar Mama who is shopping?

lol
 

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Prodigal Son
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1,297 Posts
Just Do It

petevandyke said:
-smart tire system -JUST DO IT--- My 2nd Farkle
-remus exhaust -My 5th Farkle--Have it--Do the SmartTire 1st
-replacement chip and timing remapping -_SOON, I think
-intercom system -IntaRide-RP-1--Cost Effective-Excellent per $ spent
-Ohlins suspension -MY NEXT Purchase er --Farkle
-retrofitted electro-hydraulic centerstand - ???Man that will Hurt--($$$$$)
-gore-tex raingear -Look at the FrogToggs Or the Frogg Togg Elite
-DVD-Audio and MP3 12-disk changer switch-out -? May buy the Dice- But the IPOD through the cassette ain't half bad
-heated vest, pants, gloves for cold weather -?? Yeah-but silk and polypropylene are CHEAP
-top case and saddlebag liners-Bought used on this site-cheap - keep your eyes open
-HID upgrade for headlight -My 1st Farkle and WORTH it

oh...and

the reigning Miss Asia --- WAY TOO HIGH a Maintenance Cost
 

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Premium Member
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Discussion Starter #5
early1 said:
petevandyke said:
-smart tire system -JUST DO IT--- My 2nd Farkle
-remus exhaust -My 5th Farkle--Have it--Do the SmartTire 1st
-replacement chip and timing remapping -_SOON, I think
-intercom system -IntaRide-RP-1--Cost Effective-Excellent per $ spent
-Ohlins suspension -MY NEXT Purchase er --Farkle
-retrofitted electro-hydraulic centerstand - ???Man that will Hurt--($$$$$)
-gore-tex raingear -Look at the FrogToggs Or the Frogg Togg Elite
-DVD-Audio and MP3 12-disk changer switch-out -? May buy the Dice- But the IPOD through the cassette ain't half bad
-heated vest, pants, gloves for cold weather -?? Yeah-but silk and polypropylene are CHEAP
-top case and saddlebag liners-Bought used on this site-cheap - keep your eyes open
-HID upgrade for headlight -My 1st Farkle and WORTH it

oh...and

the reigning Miss Asia --- WAY TOO HIGH a Maintenance Cost



I've re-thought it all...

Keeping my Miss Asia or Miss Texas contender...

she can check the tires
would rather hear her than the remus exhaust
won't have enough energy to worry about riding fast
Whispers in the ear are intercom enough
a suspension that bounces = holding me tighter
I can put the bike on the centerstand all by myself--show off the muscles for the chickie and all...
rain gear? Wet ain't all bad
She can play DJ with the ipod and fm transponder
heated clothing? I'd have something better to keep me warm
Don't need case liners for lingerie (for her, smartass)
would be doing something other than riding at night, so no longer a need for HID lighting...


ahh well, fun to dream


still looking for that sugar mama...
 

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Premium Member
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7,819 Posts
petevandyke said:
...if only I weren't on Santa's naughty list, I could submit my "want it" list of...

-smart tire system
-remus exhaust
-replacement chip and timing remapping
-intercom system
-Ohlins suspension
-retrofitted electro-hydraulic centerstand
-gore-tex raingear
-DVD-Audio and MP3 12-disk changer switch-out
-heated vest, pants, gloves for cold weather
-top case and saddlebag liners
-HID upgrade for headlight

oh...and

the reigning Miss Asia as a passenger (would settle for any Miss Texas contender from the last 15 years)


does anyone know of a Sugar Mama who is shopping?

lol
Pete, this is very funny. But (only somewhat) seriously, when I bought my LT last summer I started putting together a "wish list". The more info I gleaned from this site, the longer the list got.

I have found that -- over time -- items magically move from the list to the bike. :)
 

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petevandyke said:
So here's my potentially dumbass question of the evening...

If the ol' LT is on the center stand, and I am checking the front tire pressure, would it make a difference in the pressure reading if the front tire were DOWN vs. IN THE AIR?


Pete the tire destroyer
Just for the record, I believe you'll find that there should be no measurable difference in your tire pressure whether the tire is in the air or on the ground.
 

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petevandyke said:
So, emperors of engineering, what's the scoop? (and yes, I anticipate a few "what's it matter, just check before you ride and keep it at 42 front, 48 rear" responses)

Pete the tire destroyer
Pete
The only variable you haven't taken into account is whether or not the air in your tires is fresh.
It's a proven fact that fresh air stays at the same pressure more consistently.
You do change the air in your tires at the same interval as your oil, right ?

Ok,ok so the previous statement is just sarcasm :) :)

This is the truth, of all of the things on your wish list the HID headlight conversion will give you the most bang for your buck, the CQ light ones are down to $110 now.
 

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Miles of Smiles
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1,054 Posts
No Cold Temperature Display

"OK, I invested in not one but two roadgear digital air pressure gauges based on advice in the threads."

I also use this gauge which I find to be great. Compact and accurate. Also fits over the valve stem easily with no loss of air (once you get the hang of using the deflator bump to centralize the seal) Usually leave my Thomas pump and gauge on board the bike but have noticed that after a cold night 5 C or so, when I check tires there is no digital display reading. If I keep the gauge in the sun or just hold it to warm it up a little, all is well. Any one else have this happen ?
 

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Wrencher Extraordinaire
2005 K1200LT
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That is normal for LCD displays but usually they work down a bit colder. Should be good to -5C
 

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Well Pete, I have a Smartire and it is great for setting the bar first thing in the AM. I start off and within a few seconds I know what the air pressure is within one pound.. I already know from riding the day before that it will be time to adjust the tire pressure soon but the Smartire just gives me a visual acknowledgement that it is what I expect. My front drops about 1 lb pressure over a week to two weeks. Not sure why as I religiously clean the rim on every tire swap. My rear is usually fine. I just fire up my Black and Decker tire pump in the garage. For about $20 you can get yourself a great tool and you won't have to worry about how far you drove to the next station, if your quarter will run out or how dirty the ground is, and an assortment of other factors..

I would put the tire inflator on my wish list ahead of most of the stuff you have.. except maybe Miss Texas... :D In fact I would consider it in the same category as the HID.. safety.. Just like good tires.

My experience with the Smartire/Roadgear combo ... is the Roadgear is the bible and the Smartire is just a very convenient way to check tires EVERY startup. Worth the $200 and IMHO it is squarely in the safety wants lists. The Smartire should save you $200 over their life... If you don't have a Sirius Radio they might work well.. I have a Siruis radio and it interferes with the Smartire system. That is cause for another post. Bottom line is the Smartire is still worth $200..

My front tire air pressure will vary almost 20% from 65 degree tire temp to 125 degree tire temp and not always the same.. I can't place a reason but there must be a technical reason.. My rear doesn't see to vary quite 20% but the temps are higher. This summer I have seen up to 155 degrees. I have never seen the rear pressure above 58 lbs.

The more you are under inflated the quicker the pressure will rise. The more turns the tire takes the quicker the temps rise.. Net of this is unless you are going a straight 500 feet.. you need to have a way of putting air in in your garage or parking spot. Only thing you can do is say you need two lbs and check it when you start and when you arrive at the air station and put 2 lbs in.. just dont adjust to what you want.. i.e. 42..

BTW, The only time I lose a tire to cupping/feathering is with poor inflation and that usually is more than a thousand miles from home. Exactly what you don't want. I get great mileage out my stones.. probably better than most with Metzlers.. but it takes time. I am betting the Smartire will stop that.. Time will tell.. Still on my first set with the Smartire inserts.
 

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air pressure and miss Texas

I always check the air pressure before I go and never saw a difference if the bike was on the centerstand or on the side stand. I would be happy with Miss any state for for the last 20 years - However, I don't think my wife would approve....
 
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