Leaking tires

[ssco156]

Both Avon Roadrider tires on my GS450 seem to have the same problem; pressure goes down from about 30psi to 20psi overnight but then does not decrease any further. I've tightened the nuts but that did not change anything. I'm not even sure whether I have tubes so maybe someone can point me in the right direction. Thanks

[posplayr]

looks tubeless and the inside of the rim is so corroded the valve stem can not seal. Remove the tires and clean the inside of the rim. A little silicon spray will keep the rim from oxidizing farther.

People will worry about the tire slipping but I have never seen any evidence of such.

[chuck hahn]

Use some Windex and spray to see where they bubble at.

[Gorminrider]

if the rims are discovered to be really bad,and unsealable, you can put an innertube in ...you are going to have to take the tires off whatever, I think.

....did you install them yourself? It's just possible you have not got the bead actually set....being almost correct can hold air pretty well but..... Look for the tiny line on the tire. It should follow close to the rim exactly evenly....spinning the tire may show only a very small "lift"

[Brendan W]

Both leaking is remarkable.
How are the valve cores ?

[Steve]

The parts fiche for your bike shows tubes in both wheels. To start looking for your leak, I would start at the valve core. That little piece in the middle of the valve stem. Spray some soapy water on it after inflating the tire. If it bubbles, you have found a leak. Don't stop there, it might not be the only leak. Spray the entire wheel, concentrating on where the tire meets the rim.

Also, check for a date code on the tires. Not sure if non-USA tires have them, but our tires here have a DOT number on the sidewall. Look for the last part of that number, should be a slightly different looking area that will have three or four digits. If it has three digits, change the tires NOW. If it has four digits, read the code. The first two digits are the week, the last two digits are the year. For example, if you have 3709, that would be the 37th week of 2009, or about the middle of September. Chances are that the tubes are about the same age as the tires. If they are over 5 years old, consider changing the tires, most likely the tubes, too.

.

[posplayr]

For the record, GS750EX, I had slow leaks (30 psi down to 15 psi over a week) on both front and rear on relatively new tires. I removed the tires and used a stainless steel brush to scrub the crude/oxidation off of the inside lip of both rims. Then uses some fine emery cloth (800 grit) to semi polish what remained. Sprayed some silicon sealant on the bare aluminum to reduce future oxidation. Reinstalled tires and wheels and problem solved.

[Steve]

All that works great on tubeless tires, but he has tubes.

There is either a hole in the tube or a leaky valve core.

.

[posplayr]

All that works great on tubeless tires, but he has tubes.

There is either a hole in the tube or a leaky valve core.

.

OK saw no mention of that and the valve stem looks tubeless but then I'm not there.

[JTGS850GL]

Might have a tubeless tire on a tube type wheel. They have different beads and rim contours.

[Steve]

I was going on the assumption (yeah, I know) that I mentioned in post #6 that the stock bike has tubes.

Those stems could be on tubes or a tubless valve, it's hard to say.

.

[posplayr]

I was going on the assumption (yeah, I know) that I mentioned in post #6 that the stock bike has tubes.

Those stems could be on tubes or a tubless valve, it's hard to say.

.

While we are waiting for the OP to come back, my assumption is he (OP) knows how to detect air loss (soapy water) and it was at the stems which is why he posted a picture of same. Looking closely, the wheel looks like there is corrosion emanating from the hole drilled for the stem as well as lifting the black paint is certain areas.

As mentioned by someone else, having both wheels leaking is suggesting it is the rim and not tubes.