250-500cc WR300 Starting question.

I kept the title pretty vague because of the knuckleheaded circumstance that has lead me
to pose the question. I washed the bike today and when I was through I went to start it up as I always do. Started first kick but sounded a little different. I then realized that I forgot to take my
little home-made exhaust plug out so I immediately pulled it out. I've done this once before but
that time the plug shot out as soon as I kicked it. I messed with the plug to make it a little more water tight so it was fairly snug in the silencer. The motor only ran for about about two or three
seconds before I realized the plug was still in. It seemed to run ok but I'm wondering what potential
damage could be done if the exhaust is plugged with the motor running ?

I've started my bike with the plug still in. I don't think 2-3 seconds will hurt anything; it didn't hurt my bike.

haha id be a rich man if i had a dollar for every time ive done this! wash bike, go to start it, WTF? oh yeah exhaust bung. dont think it hurts it, maybe foul plug when it snuffs out at worst.

The worst that can happen is it will try blow thru any leaky point it can before it chokes... Theses New 2st are pretty tight... Don't sweat it.....

My '11 wr 300 won't start w/the exhaust plug in. It will turn over a few times, but no go. I know. I've tried and tried and tried. Watch out for the abundance of blue smoke and spooge when it does fire after pulling the plug...sort of like starting a push lawn mower after tipping it over to remove that hidden chicken wire that wrapped around the blade.

ive done this quite a few times as well...why is my bike so quiet? oh yeah..doesnt really seem to affect much..