My Kumho has me worried

[Hummingbird]

I recently had a Kumho installed on my 2007 Venture. From day one it has leaked air and I attributed that loss to normal things that tires do.

 

Day before yesterday I walked by the bike and noticed that the tire was FLAT, not low but flat.

 

I put the carbon one adapter on and lifted the bike with my sears RV/motorcycle lift. When I had it up I put 40# psi and let it sit overnight on the lift. This AM I checked the pressure and it had lost 5# overnight. I did all the pressure testing with a progressive zero loss gauge so the gauge is not a factor.

 

Prior to setting the pressure for overnight test I made serious attempts to find a leak with soapy water - nada nothing

 

My next move is to take the tire off and try submersing in water to find the culprit.

 

Has anybody else had a pressure loss that could be construed as NOT normal ? and what is my next move should I actually find something ?

[barend]

replace the valve stem? i had a tire leak down and it stopped after this simple "fix"

[gunboat]

hi dick

have you tryed taking the valve stem cover off and use your soap spray to check for a air leak out of the valve core? maybe the valve core is not screwed in all the way to seat it. also check the valve stem with the soap spray as barend suggested. if this does not find any leaks. i would pull the wheel off and set it in a tub of water, that will cover the bead area as you rotate the wheel. as you know if there are any leaks the bubbles will show up for sure.

don c.

Edited October 15, 2009 by gunboat

[Hummingbird]

hi dick

have you tryed taking the valve stem cover off and use your soap spray to check for a air leak out of the valve core? maybe the valve core is not screwed in all the way to seat it. also check the valve stem with the soap spray as barend suggested.

don c.

 

I wasn't aware that the stem was a pressure fit. should've guess it by the nuts on the stem. I'll check that before I take the tire off the bike.

 

Thanks

[wild hair 39]

put sume dish washing soap in a hand sprayer,spray it on you will find the leak

[gunboat]

dick the valve core screws into the valve stem. it is a marvious little device they are used on all kinds of wheels. they are removeable. when you add air the air chuck center pushes down into the center of the valve stem and pushes down the valve core which is spring loaded. once you remove the air chuck the valve core pushes back up and seals off the air.

don c.

Edited October 15, 2009 by gunboat

[gunboat]

the steam is not a pressure fit. at the bottom of the wheel (inside ) the steam has two o-rings. one inside the tire against a flat fitting and the other outside the tire that a screw down nut tightens against the outside o-ring. to squeezes together to hold air in the wheel.

don c.

[gunboat]

hay dick i'am up for a while give me a call. 832-265-6236

don c.

[Hummingbird]

Once again, this site, the members and their willingness to offer help and information are the GREATEST !!

 

I believe I found the problem, I don't know yet but a few hours will tell truth.

 

As suggested, I was checking the valve STEM and the first thing I found was that the nut and lock nut were less than finger tight - thus the SLOW leak ( I'm hoping )

 

I'll pressure up to 40# again and let it sit for a few hours, I'm betting I found the problem.

 

 

THANKS GUY'S

[BoomerCPO]

Giving the whole tire a thorough inspection won't hurt either. A small nail can sometimes be overlooked by a casual or rushed inspection.

 

 

Boomer......who knows them little black carpet tacks are a bugger to spot.

[gunboat]

hi dick

sorry i should have had you call me sooner. 'cause i sure can talk faster than i can type, and don't have to worry about spell check. i am 100% sure that the leak was from the nuts being loose on the valve stem, letting air to escape from around the o-rings. keep us informed on your findings. always glad to help in any way. like i told you and others my front porch light is on 24/7. so is the phone, it just may take me a few minutes to get to it.

reguards

don c.

[BigBoyinMS]

Don,

 

You-da-man! Always willing to help!

[gunboat]

hi bigboy

thanks for the kind words. you know what goes around comes around. i am honored to be a part of this extended family. we all help each other were we can. looking forward to shaking your hand & seeing you in person next month at the centeral mississippi m&e.

reguards

don c.

[Jrichard]

replace the valve stem? i had a tire leak down and it stopped after this simple "fix"

ALL in favor=====say I:thumbsup2::clap2::usa::sun1:

[Wanderer]

ALL in favor=====say I:thumbsup2::clap2::usa::sun1:

 

[BigBoyinMS]

hi bigboy

thanks for the kind words. you know what goes around comes around. i am honored to be a part of this extended family. we all help each other were we can. looking forward to shaking your hand & seeing you in person next month at the centeral mississippi m&e.

reguards

don c.

 

Same here,Sir!

Oops! Not next month! 10 days from now! Oct 25.

[gunboat]

Same here,Sir!

Oops! Not next month! 10 days from now! Oct 25.

 

oops your right, will be on the "BEND" ride next month.

don c.

[Hummingbird]

Well, the tire 'lost' 4# pressure overnight so I rechecked the torque on the stem and found it had a lot more to go so I tightened some more and pressured up to 50#.

 

I'll check this afternoon and see where it's at. If it looses any pressure, off it comes and to the wet bath. I can't believe it's a bead seat loss, the tire looks uniform against the rim all the way around on both sides.

 

The only frustrating thing is the leak, can't ride anyway. It's raining and will 'til Monday, not to mention that it's 37 degrees.

 

I would like to get this resolved because there are still ( hopefully ) a few good fall days left for riding.

[gunboat]

hi dick

after tighting up the nuts on the valve stem & adding air. did you use the soap soluation and sprayed it all around the valve stem to check for any more leaks? would not think those's o-rings on the valve are bad. but if you have to take the wheel off to put it in a tub of water to check for a leak. as barend suggested might as well go and have the valve stem replaced. i am sorry your haveing so much trouble with this. will give you a call later this enving to find out more.

reguards

don c.

[Hummingbird]

UPDATE

 

Ok - this must be the dumb and dumber sequel. I have done everything I could do shy of putting the tire in water. The reason I didn't do that was because I couldn't find an available tub so just moments ago I put 90# of air in it for the second time.

 

I AGAIN checked the bead on both sides with the tire flat as well as soapy stuff in the stem. NOTHING, no bubbles, no movement. I decided to take a real close look at the tread since I had an LED flashlight checking the bead.

 

Never guess what I found with the flashlight and 90# of air - pictures attached. The first picture is the culprit, the excessive air pressure must have pushed it out a little 'cause I swear it wasn't there the last 2 times I looked. The diameter is less than a pencil lead and almost 1/2" long.

 

The second picture is what happens to your finger when you push a plug in as hard as you can and it goes all the way and pinches your ( my ) finger.

 

I'll know in the morning if that was the only problem and no, I not worried about plugging a tire. I've done it for years and never had a failure, no need to start worrying now.

[gunboat]

hi dick

great news to finaly find the "problem". that's a nasty looking cut on your finger. thanks for the up date.

best reguards

don c.

[BigBoyinMS]

It's always good to see a resolution. Glad you got it figured out!