There are certain tires that will just be a pill, no UST are not always the way, there have been enough guinea pigs to weed out what works. Do some searching and you will see. What has worked for me- WTB Nano, WWlt, and Stout. Stans Raven 2.2. Panracer Rampages and IRD Fire x/c Pro. Right now I just mounted up CST Comp and Critter without a lick of brew seep. Of course all are 29" wheels on either Flows or WTB laser Discs. Two tires that I would not recommend for the rocky North are the paper thin over priced Racing Ralphs and Conti Mt. king. I know others have had good luck with Conti's but not I. Both of these seeped for more then 24 Hrs before finally sealing, then very few rides before sidewalls failed. For what its worth these are just my own opinions.