Just so you know. I only order blank cartoz. And I've seen 2 reports of prefilled eGo cartoz with bad taste.
I have had some very bad results with pre-filled cartos, both 510 and KR808D-1.
Unfortunately, the eGo cartomizers that went bad were blank ones.
I have tried to pin down what makes a atomizer / cart take on a the horrible taste that the ECF has numerous threads on. Seems like for my experiences it is the wicking material that the atomizer wire is coiled around.
That is why I was very disappointed when I took the eGo carto apart and saw that it is very similar in design to a atty. There is not a good way to clean an eGo carto and of course, a dry burn is out of the question.
Here is a post to a thread where I posted a theory about the terrible taste.
I have a theory about the horrible taste. Unfortunately, it isnt based on any Scientific facts. So take it for what its worth.
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I have used 510 Kr808D-1 RN4081 cartos for a while. I found what I consider to be a trend when it comes to getting a horrible taste. Ive noticed that the chemical taste seems to occur when the carto has been used and then sits unused for a period of time.
I first noticed this with some RN4081 Cartomizer from Smokestik. They came prefill and the first one I tried was fine. I use my RN4081 as a backup so it doesnt get day to day use. I pulled it out after about a week of non-use and the carto had the Chemical taste bad. I dissected it and it wasnt burn. In fact it looked new. But it smelled terrible. Maybe it was just a bad cart? I tossed it as a bad carto.
As a test, I decided to vape a RN4081 carto regularly and see when the terrible taste occur. So I vape on a new pre-filled carto in the mourning and it went all day with no problem. Around 4:00 pm I refilled it seemed fine. I used it for 3 days straight with now problems. I concluded that the first carto was just a bad one and put my RN4081 back in the drawer as a backup.
About 2 weeks later, I pulled it out while waiting for my eGo to charge. The first hit of the cart was ok but the second was brutal. So I took it apart and once again, it looked ok. No burning but smelled horrible.
So a thought occurred to me. Could it be that if a carto is used and then left to sit for awhile that something happens inside the carto? A chemical reaction? My thought was that perhaps the nicotine or the flavoring was breaking down the wick or filler material or both?
Now fast forward to the new eGo. I got One blank eGo carto from TW with an order of a 1000mAh battery. I filled it and was impressed so I ordered a 5 pack from cignot the next day. I took about 5 days for my 5 pack to arrive and during that time, I refilled my first eGo carto about 4 times. It was working good.
Then the 5 pack from cignot arrive so I put the first eGo carto from TV away and filled up a new one with a new flavor. It taste great and I used it for about 3 days. Then I went back to the first carto. On the second hit, I could taste a hint of that chemical taste. At $4 a piece I was going to throw it out so I ran to the sink and flushed it out with warm water.
I let it dry out and then try it. It was fine. No chemical taste. I have refilled it a few times and it is going strong. No chemical taste. Just like my other eGo Cartos.
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So here is my Theory.
1) If a carto is used and then left to sit for a period of time, The chemicals in the e-Juice (Nicotine, Flavors, Sweeteners, etc) react with the carto filler/wick and produce the terrible taste. It isnt burning, it is a chemical reaction.
2) Once the reaction occurs, if it is wash out immediately, the carto is not ruined.
3) If a Carto is used constantly, the chemical reaction does not have time to occur or build up to significant quantities to cause the chemical taste.
4) Perhaps once the chemical reaction occurs, it does not occur again.
Once again, Im just throwing this out and do not have any scientific evidence to support it. Maybe some of the chemists out there can comment of the reactive nature of some of the material inside a carto, Kevlar and filler material, with the chemicals that make up a flavored e-Juice.
If you look at the last post, you'll see that I made an update about All of the cartos going bad.