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I recently picked up a pair of wheels and tires (A-7120) off ebay.

They were glued so I soaked them in acetone as ive done many times before and was able to get them off the wheels without issue.

After cleaning and drying them off, one tire has clearly shrunk. Does anyone have an idea of what might have happened?

Both tires were soaked in acetone? That certainly is strange, I've never heard of acetone shrinking rubber tires, but that wouldn't be relevant anyway if you soaked both. Very weird!

Did you measure the wheels?
And did you try to remount them?
Are you sure one tire didn't swell up?

Usually, rubber tires would swell with acetone and over time should shrink down back the normal. I don't think I've seen a rubber tire shrink, but it looks like it has happened to you.

I would put them both out in the sun or on a heater duct/radiator for a few days, and see if they change.

Coelacanth wrote: ↑Tue Oct 06, 2020 5:57 pm Both tires were soaked in acetone? That certainly is strange, I've never heard of acetone shrinking rubber tires, but that wouldn't be relevant anyway if you soaked both. Very weird!

Yes both were soaked and for the same period of time.

RC10resto wrote: ↑Tue Oct 06, 2020 6:53 pm Did you measure the wheels?
And did you try to remount them?
Are you sure one tire didn't swell up?

Didnt measure the wheels but theyre both the same Losi logo wheels from the JRX Pro. Im able to mount them but the one is clearly smaller then the other lol. They do swell up after soaking but then shrink back down to normal size.

jwscab wrote: ↑Tue Oct 06, 2020 7:38 pm Usually, rubber tires would swell with acetone and over time should shrink down back the normal. I don't think I've seen a rubber tire shrink, but it looks like it has happened to you.

I would put them both out in the sun or on a heater duct/radiator for a few days, and see if they change.

Ive soaked several pairs in the past and never had this issue. I tried drying them in the sun, boiling them in water and resoaking them again to no avail.

Im starting to think that someone tried baking them in the past and the high heat melted/shrunk it down. If you look at the one that shrunk, it has a glossy appearance.

I wonder if the tires originally came from different manufacturing batches and happen to be made with different rubber compositions. It's about the only explanation that makes sense, if everything you did to both tires was the exact same procedure. Strange.

Coelacanth wrote: ↑Wed Oct 07, 2020 2:13 pm I wonder if the tires originally came from different manufacturing batches and happen to be made with different rubber compositions. It's about the only explanation that makes sense, if everything you did to both tires was the exact same procedure. Strange.

Super strange and a bummer because I now have only one good tire

Anyone need a single 7120?

I was just looking up some tire/acetone related stuff, and came across some info that clay compound tires will shrink and harden when exposed to acetone. I wonder if there was something incorrect in the rubber compound that was used to make that particular tire which caused it.

Lowgear wrote: ↑Tue Oct 13, 2020 5:08 am I was just looking up some tire/acetone related stuff, and came across some info that clay compound tires will shrink and harden when exposed to acetone. I wonder if there was something incorrect in the rubber compound that was used to make that particular tire which caused it.

Thanks for the info. I'm going to be a bit more careful in the future... instead of soaking, I'll try the vapor method to release the glue.

Its not the first post on here about this. I did the same thing but at the time I was told I had different tires to begin with Mine did the exact same thing as yours. For the record they were the LOSI stagger rib same as yours also. After a couple years I found another tire in our singles thread that sometimes shows up in the b.s.t area and went to mount them. The new single mounted nicely...the old tire that went through the acetone method cracked and pretty much deteriorated so badly that it went to the garbage bag. I don't know if I still have the single or not anymore but I ended up never submersing the tires in the liquid acetone again. Just used the vapor from it and haven't ever had that issue again.

Todd