Is it normal for a mountain bike tire to go flat riding over a rose bush thorn?

Question

I rode over a rose bush thorn and my tire went flat. Is this just a cheap tire or would any mountain bike tire do that?

Answer 1

Unfortunately, yes.  Anything that punctures the tire and tube will cause it to go flat very quickly.  I use Slime in my tubes and haven't had any flats since.  It may not stop all flats, but it sure makes a difference with the small stuff that happens most often.

Answer 2

Yes.  That is perfectly normal.  Next time you ride through a patch of thorns you may be able to prevent a flat by immediately stopping your bicycle and reaching down and pulling the thorn out.  Very often a flat is not caused by the initial run over a thorn, but the repeated riding over it as that will push the thorn further into the tire and puncture it.  Pulling out the thorn immediately after riding over it might prevent that from happening.  Won't work every time, but if you don't pull it out you're almost guaranteed to get a flat.  At least if you pull it out you've got a decent chance of preventing the flat.  

Also, although putting Slime or some other tire sealant will do a reasonably good job in preventing flats, it adds a considerable amount of weight to the wheels which will make the handling of the bicycle feel a bit sluggish.  Sometimes when you've gotten to many holes in the tube or if the hole is just too big not even Slime can stop the leak and when that happens you just end up with a slimy, sticky and stinky mess.  In my 10+ years of being a bicycle mechanic nothing p*ssed me off more than having to clean up a Slime mess on someone's exploded tire!