Rear tire losing pressure, dealer stumped

[Ride365]

12 hours ago, bwringer said:

Yep, poke the valve stem. I've seen a few that actually sealed OK when you're just looking, but start hissing if you poke them. Valve stems can also move at highway speed and leak rapidly.

Hey is this the same bwringer from Stromtrooper? 

[bwringer]

3 hours ago, Ride365 said:

Hey is this the same bwringer from Stromtrooper? 

Yep, that's me!

[larolco]

You two interlopers go back where you belong! This here's a Yamaha leak, not a Suzuki leak. 

[johnmark101]

On 9/14/2020 at 3:36 PM, Dirty Randy said:

I have done this at my neighborhood pool ... people though i was some crazy guy 😄 .. HOA doesnt say anything about motorcycle tires in the pool ... definitely does now 

That is hilarious!!  😄

[bwringer]

On 2/9/2021 at 5:25 PM, larolco said:

You two interlopers go back where you belong! This here's a Yamaha leak, not a Suzuki leak. 

LOL... we are restless spirits, belonging to both worlds and none...

 

Tangential anecdote: A friend of mine once, no kidding, needed a front tire for his vintage Suzuki in a hurry on a road trip. The new tire he had just installed was defective and literally falling apart in chunks.

On the horizon was a huge Harley sign. I knew several models, such as the Dyna, used the same 100/90-19 front tire size. We were happy to bring in the bare wheel if they didn't have metric tools, or even install the tire in the parking lot.

The service manager insisted that they ONLY had Harley tires, and did not have any Suzuki tires. We were riding Suzukis, so obviously the only thing that would possibly work was a Suzuki tire from a Suzuki dealer. The debate went in circles for quite some time. I finally got her to check and see whether they had any in stock. Turns out the whole thing was in vain since they didn't have any in stock anyway (never mind it was an enormous shop with at least 20 customer bikes and hundreds of new and used bikes for sale, several dozen wearing this size...)

She helpfully called the local Suzuki dealer for us and determined that they had a Suzuki tire (*cough* Shinko) in stock in the correct Suzuki size to fit a Suzuki motorcycle. Then gave us directions that took us ten miles in the exact opposite direction... it was a looong day.

Edited February 11, 2021 by bwringer

[Lone Wolf]

On 9/7/2020 at 1:36 PM, ecognomeist said:

The bike is losing pressure from the rear tire.
...my local dealer was unable to find anything wrong with the wheel or tire,

OK - I had the same thing just happen. Very slow leak.

I sprayed everything with soapy water just like you did. Could not find the leak.
It was a brand new valve stem, so I just made sure the core was tight because sometimes they aren't.

Today, I got a Q-tip and FULL STRENGTH dishsoap (Dawn). I put a generous amount of dishsoap on the Q-tip and applied to the valve stem where meets the rim, and inside where you fill the air. Then I put more soap in there, repeatedly, to make absolutely certain that the inner valve stem had a soap layer (it was a 90 degree stem).

After 3 minutes, a bubble the size of a BB started to appear at the end of the valve stem. It was not manifesting with "soapy water" which I did twice before, but the full strength thick soap did the trick. I replaced the inner core of the valve stem, and of course the leak stopped. Mine was only loosing about 3 lb a week in the front - but the rear lost nothing. Enough to drive you crazy.

On 9/20/2020 at 7:12 AM, 2linby said:

check the cheap things first!

1) Pull the Schrader valve, (Not the stem) clean the inside of the valve stem with a Schrader valve tool and replace with a brand new Schrader valve (easily purchased at a auto parts store). 

His list would fix the issue I had.

On 10/19/2020 at 8:08 AM, ecognomeist said:

I finally had some time to look into this again over the weekend. I inflated the tire to about 40psi and sprayed both the tire and valve stem generously with soapy water. I was not able to detect any bubbling. But it's still losing pressure- down to 25psi today.

My plan now is to start working down @2linby's list, although I admit to being a bit a newbie when it comes to maintenance

A month after 2linby's post you were using soapy water, did you ever follow the list and replace the inner core of valve stem? If not, you could try diagnosing it with the full strength (thick) dishsoap applied inside stem with Q-tip. Also where the stem meets the rim.

It is unlikely to be leaking from the bead of rim unless the person changing the tire didn't clean it. I change my own tires, and scrub that area down with scotch brite pad after removing the old tire.

[betoney]

15 minutes ago, Lone Wolf said:

Today, I got a Q-tip and FULL STRENGTH dishsoap (Dawn). I put a generous amount of dishsoap on the Q-tip and applied to the valve stem where meets the rim, and inside where you fill the air. Then I put more soap in there, repeatedly, to make absolutely certain that the inner valve stem had a soap layer (it was a 90 degree stem).

After 3 minutes, a bubble the size of a BB started to appear at the end of the valve stem. It was not manifesting with "soapy water" which I did twice before, but the full strength thick soap did the trick. I replaced the inner core of the valve stem, and of course the leak stopped. Mine was only loosing about 3 lb a week in the front - but the rear lost nothing. Enough to drive you crazy.

That's good info to have, thanks for posting it.  👍

[daboo]

I had a leak on my last tire like this.  Slow, but definite.  

I finally took the wheel off, aired it to about 50+psi, and put it in the bathtub.  I'd have used a swimming pool, but didn't have one.  

I finally found the leak.  It wasn't the cuts I could see.  It was the tiniest tiniest cut.  I couldn't see the cut without the air coming from it.  The difference though, was that it went all the way through.

Chris

[Lone Wolf]

15 hours ago, daboo said:

I had a leak on my last tire like this.  Slow, but definite.  

...It was the tiniest tiniest cut. 

If the cords of the tire were OK, this Ride-On may seal it.

I have been running it in the rear tire that I changed a few months ago, and now that I have the front done and no valve leak I will put it in that tire. 

This video was posted on pg2 of this thread, it is worth a watch.

This stuff does not have some of the drawbacks of the old tire sealants like "slime". It does not get on the rim. It is not runny. When you remove a tire that had Ride-On, the stuff is clinging to the underside of the part of the tire that contacts the road (not the sidewalls), I balance my new tires, and was a bit concerned this stuff might collect at the bottom of the tire when parked and be out of balance, but it doesn't do that. Very smooth - it will correct an out of balance tire.

Edited February 14, 2021 by Lone Wolf

[betoney]

29 minutes ago, Lone Wolf said:

If the cords of the tire were OK, this Ride-On may seal it.

I have been running it in the rear tire that I changed a few months ago, and now that I have the front done and no valve leak I will put it in that tire. 

This video was posted on pg1 of this thread, it is worth a watch.

This stuff does not have some of the drawbacks of the old tire sealants like "slime". It does not get on the rim. It is not runny. When you remove a tire that had Ride-On, the stuff is clinging to the underside of the part of the tire that contacts the road (not the sidewalls), I balance my new tires, and was a bit concerned this stuff might collect at the bottom of the tire when parked and be out of balance, but it doesn't do that. Very smooth - it will correct an out of balance tire.

I have never heard of this product before, it sounds promising in that it is not runny or make a mess all over the rim. 👍

[Lone Wolf]

1 hour ago, betoney said:

... it sounds promising in that it is not runny or make a mess all over the rim. 👍

Yeah, here's a look inside the tire (one minute video)

And here it is being put into an FZ-09 tire

[daboo]

Actually, Slime works like that too.

I had a tire that got a puncture a few weeks after it was installed.  My wife wouldn't have been happy with me trying to "save money" by riding a motorcycle to work, if it was going to cost us a new tire every month or so.  

So I decided to try Slime.  It saved at least 4 punctures in that rear tire before I changed it out.  When it was removed, I asked to watch.  I'd read all kinds of stories of corrosion, messes, etc.  When the mechanic took the tire off, he made a really LOUD exclamation, "LOOK AT ALL THAT MESS!".  It would've been better if there'd been some mess.  There was a small amount that fell onto the hub and dried, but that came off easily...it's water soluble.  The rest was inside the tread area of the tire like you see in the video above, except it was black, not orange.

I would've put Slime in the tire in a heartbeat, but I had balance beads in there.  The to products don't work well together, as you can imagine.    Ride-On is a great product and I have a bottle of it myself.  But Slime is pretty good too, and can be found easier.

Chris

[sirepair]

One thing not mentioned is porosity of the wheel castings.  It is possible that the air is leaking through the wheel itself.  Not a common issue, but can happen. 

I worked at an auto parts manufacturer that made cast aluminum lower engine blocks.  Each part was capped and filled with helium to test for leaks.  Any "leakers" had to be ran through a process that filled the porosity.  

If this is the case, the wheel should be replaced, though the inside could be painted which would fill the holes.

Like others have stated, likely a valve core/stem, debris along the bead of the rim, or a small hole/defect in the tire. Hope you get this figured out.