Recently got a flat from a nail and plugged it up Ive heard from a friend it can blow at high speeds but how possible is it if the hole is in the tread line and not making contact with the road? I would assume its a safety hazard if the friction of the road was making contact with the plug which it isnt how much of a risk is this when Im riding vs a hole on the surface of the tire?
edit: Ah, sorry, did not realize this was for a motorcycle. Please disregard what I said below as it applies to cars!! Don't plug motorcycle tires. Depends on how the plug was done. If you went to some auto store and got the plug and did it yourself, that is a low quality cheap plug and I wouldn't depend on it very much. But then again, I drive my car hard and fast. A properly done repair requires removing the tire from the rim and inspecting the INSIDE of the tire for damage as well. Then it's plugged AND a patch is applied over the plug from the inside. Remember, just because the outside of the tire looks okay doesn't mean that the inside of the tire isn't messed up from the nail. Those rope plugs you get from Walmart and Autozone are cheapo fixes that will be okay for the majority of cars on the road but if you are drive your car HARD, have the repair done properly by a GOOD tire repair place.
I've plugged many motorcycle tires over the years. I would never plug a tire on a bike pushing the envelope in the canyons or on a track day, but I have never had a problem using a plug for a basic street bike. I don't have the cash to throw down hundreds of dollars every time I pick up a nail or screw. Plus, I'm of the opinion that it's no more likely that the plug will fail as I am to get a flat for any other reason.
Plugs are not an approved repair for passenger radial tires and will void your tires manufacturers warranty. The only safe way to repair a tire is to dismount it from the wheel and inspect the inside of the tire for damage to the inner-liner. If it is OK then the puncture should be repaired with a combination patch-plug.
