Rear tire leak

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GPRIDER

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I have a leak in my rear tire. After very close inspection by my and a tech at a dealership neither of us could find anything in the tread. We both used soapy water all over the tire and no bubbles. I brought it home and submerged it in the sink up over the rim with 28 lbs of pressure and then with 50 lbs of pressure slowly rotating it around. No bubbles. Checked and double checked the valve stem and core. Seem to be good to go. So after I did all that, I put 40 lbs in it and let it set for 17 hours and checked it this morning. Lost 10 lbs. Went from 40 to 30 in 17 hours. Any ideas?

GP
 
If it isn't the valve stem, valve core, a hole in the tire itself or a leak where the bead seals to the rim, I would wonder if there is a crack in the wheel casting itself. Might not see anything unless the entire wheel was submerged (to the probable detriment of the bearings and ABS stuff).

This doesn't seem very likely to me unless the wheel was involved in some sort of mishap - on the road or in the shop. I would probably dismount the tire and examine the inside for any anomalies (rim too). I would thoroughly clean the rim where the bead makes contact, clean the tire bead (and look for bead damage). Replace the valve and core and try again.
 
Thanks Ross. I took it down to the shop i use and they were too busy to get to it right away. I had to leave it with them, so I don't know how close they will check it. I told them to break it down and inspect it and change the valve stem just for good measure.

GP
 
Tip: add glycerin or corn syrup to your soapy water solution. It helps maintain the film when chasing slow leaks. I use 50mL of corn syrup and 250mL of dishsoap in 1.5L water.

Or buy children's bubble solution at the dollar store. It also has a high film strength.
 
Good tip Torch, but don't think it would have helped in this case. I completely submerged portions of the tire and rim and then slowly rotated it. Never saw one bubble with 28 lbs of pressure or with 50 lbs of pressure. Craziest thing. Had the tire taken off and they cleaned the tire side of the rim up and put a new air valve in it just for good measure. Seems to be holding air for now.
 
Had wheels on a used bike I bought where a crappy Yamaha shop used metal tools when changing tires for prior owner. Grooved front and rear rims where beads seal. Had to gently sand the grooves smooth and then used bead sealer. Both tires have held fine over 3000 miles so far. No leaks whatsoever. Good luck.
 
I got the tire back and the shop said after cleaning the rim good they remounted it and checked it hours later and no leaking. So I take it home and put it back on the bike. I checked it a few days later and it had lost 20+ pounds. I aired it up to 42psi and checked it the next day. Down to 40. Ok. I let it sit and check it 24 hrs later and it had about 5psi. What tha? Going to take it off again and submerge it in the sink again. Very confounding problem.

GP
 
I'm running Avon Storm 3DXM's. My preffered tire. Never had a problem like this with a Storm before, This one just has 2,000 miles on it. Your idea is a more diffinitive, but pricey, way to check it though. Looks like Yamaha doesn't have rims for the 2012 anymore.
 
I had a weird leak in my front tire a few weeks ago. It was actually leaking between the stem and the rim. Changed the stem and it was fine. It was only leaking a couple PSI a day. Found it by filling the wheelbarrow with water and very slowly looking for any bubbles. Make sure the stem is fully submerged when you get to that spot
 
Been there done that already. Bottom 3rd of the tire was submerged which covers the stem when rotated around. No bubbles even when I wiggled the stem around under water. The shop I used, broke the tire down, cleaned up the inside of the rim and replaced the valve, then remounted it. Thought it was fixed, but after about a week, I checked it again and it was low. I aired it up to 42 and it just lost 2lbs overnight. I checked it 24 hours later and it was down to 5lbs. So it lost 35lbs in 24 hours. I pulled the wheel off today and am dunking it in water again. Not one bubble anywhere on the tire at 40lbs. Trying it at 30 to see if it leaks more at a lower psi.
 
I used soapy water to start with but didn't spray it on. I had a bowl of it and just rubbed it on. I'll try and spray it on tomorrow. Maybe it will show something, but I think the shop i took it too sprayed soapy water on it the first time and saw nothing.
 
If it leaks more at lower pressure, the problem is more likely at the bead - tire bead damaged/defective or rim is gouged.
Sometimes, a rim sealant is the only solution for a tire with minor bead damage. Can help with gouged, dirty or corroded rim sealing surfaces too but better to clean, repair or replace.

If you are looking to replace a rim, anything 2008 or later will work. You'll have to check on colors...
 
I'm running Avon Storm 3DXM's. My preffered tire. Never had a problem like this with a Storm before, This one just has 2,000 miles on it. Your idea is a more diffinitive, but pricey, way to check it though. Looks like Yamaha doesn't have rims for the 2012 anymore.

You're going to need a new tire eventually some day.
 
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