Down 5 lbs in one week... cause for concern?

Joined
May 15, 2013
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Redlands, CA
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2005 st-1300
Hi guys,

the st1300 sat for a month and a half and when I checked pressure it was down to 17. So I put it up to 42 eight days ago, and checked again this morning back down to 37. This is the rear wheel on a bike sitting in garage in temperate climate (so cal).

I' checked the tire over and didn't see anything obvious in terms of puncture, valve looks visually ok. Tire is Michelin Pilot gt4.

I've never seen a tire go down that fast, should I be thinking about replacing? It's still got a lot of miles to go.

Thanks for input.
 
Joined
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Fort Worth, Texas
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Either a very small puncture or a loose/plugged valve core.
Sit behind the wheel, spray with copious amounts of windex and look for tiny bubbles...don't forget the sidewalls. Then sit were you can watch the valve stem and spray it as well.
Do not spray so hard that you create bubbles...kind of defeats the purpose.
 

dduelin

Tune my heart to sing Thy grace
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+1. Look for small foreign object puncture. Depending on the miles I'd probably plug it with a gummy worm if a clean small hole.
 
OP
OP
red dirt cowboy
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ok tried that, yeah it looks like it makes bubbles at base of valve. I have a bottle of green slime here, is that worth a try?
 

Uncle Phil

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Nope, I'd just replace the stem. If it's leaking, it may fail suddenly and leave you in a mess. You should be able to replace the stem without removing the tire, just by breaking the bead so you can get to the stem. Cut the old end in the tire off, give it a yank, then pull the new on back through the whole. Air her up, and you should be good to go.
 

Slydynbye

Will ride for Pie
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Slime won't work but, it will make a heck of a mess when you go to change the tire and or replace the valve stem.
perhap you should source a right angle valve stem like the ariete valve stem.
 

wjbertrand

Ventura Highway
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I wouldn't trust any kind of instant repair stuff to fix valve leak. Take the opportunity to install a metal stem with an angle, and have no further worries, not to mention easier access.
 
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ok tried that, yeah it looks like it makes bubbles at base of valve. I have a bottle of green slime here, is that worth a try?
NO!! Replace that stem. While you are at it, replace the front one too. A rotten valve stem can leave you stranded, or worse.
I change them at least every other tire change. They are cheap. O'Riley's has them, about $4 for two.
 

970mike

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st1300doug

I replaced my front/rear valve stems years ago....with the high quality ARIETE valve stems. They are in 90 & 70 degree angles; in colors too. I lose then than 2lbs. in a month ever since, if that.
 
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I support the remove and replace statements. I upgraded to the metal 90degree valve stems and don't have any leaks from there or rot to worry about.
 
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OK, the NO's have it. Since you are going to replace the stem, perhaps with a right angled one, consider a "T stem like that used on external Tire Pressure Monitoring Systems. If you decide to use am external TPMS later, you are set. The pressure sensor goes on the leg standing straight up and you add air through the horizontal leg. BTW, if you go right angled stem, make sure you get the size for your wheel's hole.
 
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I would go straight aluminum stem. I use FOBO TPMS. I would not put a 90 stem on with FOBO. Have never had a problem getting air in them.
 

ST Gui

240Robert
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Uncle Phil said:
If it's leaking, it may fail suddenly and leave you in a mess.
+1 Dynamic Deflation could be more fun than you want to have.
 
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At first I thought this was about some special diet that you discovered. :)
Haha me too, I was ready to sign up!
I'm in the camp of replacing the valve stem immediately. I had an Ariette fail and have a new one in hand to replace it when tire change time comes around. It very slow right now, now where close to 5 in a week,maybe in a month, but it makes a bubble with soapy water.
 
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