Once you remove the tire you will likely but not always have to put new sealant in to get the tire to seal. I would say you could run your psi as low as 30-35 safely. The tires will hook up much better. You should still carry a tube on your rides. If you rip a hole in a tire there is no trail fix for it. I've know quite a few people who stoped running tubeless and started putting tubes in their tubless rims. Best of luck. If you have problems run a search and that should help answer questions.sebastian21 said:hi, i have always used tires with tubes, but i just bought a cannondale scalpel 2000 that comes with tubeless tires. and since tis is new for me, wat do i have to worry or check when removing the tires, also should i apply a sealant? and what would be a good ait pressure , now imussing 40 psi. with tubes i was running at 50 psi.