Slime to stop a slow air leak in a tube????

[scottyintex]

I have a slow leak in the rear tire of my cycle..a Metzeler block K for sidecars. It is a relative new tube....less than a year old. I have thought about using slime in the tube to seal it. Anyone have experience using slime in the tires?

[Rob Valdez 79 R65]

How fast is the leak?  It is normal for good natural rubber tubes to lose air on a regular basis.

[Bengt_Phorqs]

I did slime a tubeless tire on the R100GS "ghost bike" but only after removing the tire and cleaning the rim a couple of times.  Nothing seemed to work and I slimed it out of frustration.  That did the trick.  Didn't really want to do it but it never leaked a bit after that.

But like Rob asks, how slow is it?  If you are losing several pounds of air pressure each week then that should confirm it.

[scottyintex]

I aired that tire up two months ago. I run 36 psi in the back tire due to the sidecar. I have valve stem caps with a air pressure gage built into them. They show a green ring as long as the air pressure is above 32psi. Well today it was a red ring meaning a pressure drop. It has been cold and I have not ridden the cycle in about 2 weeks. So, really the drop was in two weeks....at least from 32 psi. I make a quick glance at the stem gage.....if it’s green I go. The tire had 18 psi. This is the only tire that leaks. The other two are normal motorcycle Michelins. I checked them and they were down no more than a pound or two. Think I will see how long it goes before I had to fill it again.....but would like to hear from those who have tried it.

[Barry]

As has been said and whether the bike is ridden or not I find natural rubber tubes loose 1/2 to 1 PSI every week or there abouts.  I just check them every week or at most every 2 weeks - It's a nuisance.

I've never had any luck with slime fixing a puncture but maybe it would seal the inside of the tube and slow down the natural loss due to porosity of the rubber.

[Dizerens5]

Tyre sealants like Finilec are supposed to be for tubeless only but they can work well on tubes. Last year I stopped for a rider of an old (classic) Triumph twin with a total flat rear, I lent him my can of sealant. We squirted a lot into the tyre, there was quite a bit of slime leaked out around the valve, - then he rode off on what looked like a perfectly good tyre. So it can work on a tube. Just maybe not always. And maybe not for long! Does anyone have some real experience?

[Barry]

I've seen the stuff used twice. Once in 1975 on as it happens my mates Triumph T140V. My mate never had any luck we bought two identical new T140V's and his had piston slap and mine didn't and he got the puncture miles from home and.... Anyway It didn't work but it did make a big impression on the guy at the shop we took the wheel to for a repair. He wasn't pleased with us. BTW we got the T140V's very cheap courtesy of a failed export order to the US because they were right foot gear change which I think had just been banned over there.
 
Used it more recently on a small puncture on my sons tubeless car tire. Didn't work. Maybe I've been buying the wrong stuff in the aerosol cans. Never actually tried the green slime used by cyclist if that's what you mean.

[Rob Valdez 79 R65]

Tyre sealants like Finilec are supposed to be for tubeless only but they can work well on tubes. Last year I stopped for a rider of an old (classic) Triumph twin with a total flat rear, I lent him my can of sealant. We squirted a lot into the tyre, there was quite a bit of slime leaked out around the valve, - then he rode off on what looked like a perfectly good tyre. So it can work on a tube. Just maybe not always. And maybe not for long! Does anyone have some real experience?

No real experience, here, but I would rather replace the tube than to ride around with that stuff in my wheel.  

[donbmw]

The green slime works best on tubless tires. Have used it on a few with no problems. Have used other types  of sealer a few time on tube tires with hope that it would at least slow the leak. Never had to test this until a couple years ago. Had the rear tire go low, was able to get to a air hose and aired up tire. I stopped about every 30 miles to check press I had about 100 miles to get home. When I finely had to to look I found that there was a nail puncture but no nail.  I can only think that using tubless tires with a tube. The sealer was able to seal the hole and let me  get home. The slime may or may not work on tubes.

Don

[Dizerens5]

So would I Rob, but if the stuff just gets me home that's a plus!

[Rob Valdez 79 R65]

So would I Rob, but if the stuff just gets me home that's a plus!

I felt that Scotty was implying he intended to ride it like that until the tire wore out.

I could be wrong.

[Bob_Roller]

To get back to the original problem, I would remove the wheel/tire from the sidecar and spray a soap solution on the tire/bead area and valve stem to check for leaks .

 Check the tightness of the valve core .

One really remote possibility that had me baffled for a while, was a valve cap the slightly depressed the valve core pin when it was tightened up .

[Rob Valdez 79 R65]

One really remote possibility that had me baffled for a while, was a valve cap the slightly depressed the valve core pin when it was tightened up .  

Yeah - I insist on having good, metal caps with a rubber gasket inside, on my valves, one of which I believe came with the bike - it has the little rubber cone you remove to expose the valve core tool.

(Rear wheel, Bob.)

[Bob_Roller]

I use the valve caps that are used on my employers 737 aircraft, they are brass, with a recess in the rubber seal inside for the valve stem pin to rest in and not have a chance of depressing the pin .

[Rob Valdez 79 R65]

I have one like this BC035NI (original)



And one like this  BC043NI (good-quality replacement)



Source: http://www.extair.com/brass-valve-stem-cap.html