Scooter,
I don't know if you've been following the forum as of late, but there's been some controversy on your question's subject-matter. I'm probably not the most qualified to answer your question because I'm still trying to refine my Klasse technique. But I hate to see a thread with zero replies, so I'll give you what most of the other forum members have experienced when using Klasse.
Anyway, the answer to your question is yes....the Klasse coats are still holding up and should hold up for several months, especially if you have more than 1 coat of KSG and you QD on a regular basis. Depending on how many coats of Blitz you have (as well as several other variables), your carnauba topper should last you about 4-10 weeks. In terms of "how do I know it's still working", your Blitz will provide slickness and beading whenever you wash your car as well as an unbelieveable deep shine. After the Blitz has worn off, your Klasse coats should still be very shiny and your car should still be soft to the touch. If by chance the beading on your car starts to go away and is replaced by the water starting to sheet, it doesn't mean your Klasse is no longer protecting the car, because a few people (including myself) have reported the same results after a few washes. However, the vast majority of people experience a great amount of beading and a decent amount of slickness on their Klasse coats for several months.
As for "when should I apply Klasse again?", you should apply coats of KSG whenever you have time, however you'll get diminishing returns after about 4 coats. Then you can reduce the fequency of applying new coats to maybe weekly. Before you apply another coat of KSG, you must remove the carnauba topper by washing your car lightly with Dawn dishwashing liquid. When you get bored of putting on the KSG coats, then you could switch to applying coats of carnauba. I'm not sure how much time you want to spend on your car, but one of the great things about Klasse with carnauba on top is that you can constantly tinker with your car. eg....when your coats of blitz wear off, you can try some of the pinnacle waxes, see if you can detect any difference; or you can apply a few more coats of KSG and then reapply a carnauba topper...etc..etc. If you don't wish to spend a lot of time, you can apply Klasse (multiple coats) two or three times a year, making sure one of those times is right before winter. Your car should have no problem making it through the winter season, especially if you've applied multiple coats of KSG and Blitz and you QD from time to time. Since I live in Southern Cal, I will always have good weather and will be laying down coat after coat of KSG/Carnauba every weekend. I'm not sure what type of climate you live in, but my basic philosophy is not to wait to reapply Klasse when it needs to be reapplied or when the protection is gone. My goal is to have maximum protection and shine 365 days/year. Sure, one of the benefits of Klasse is that it lasts a long time, but you'll get better results by spending more time with it.
I hope this helps. I tried to answer all your questions..and I'd love to hear what anyone else has to add (or correct).
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