Question on single muffler 87ninja250r

[Greatjobdani]

Just got my dads 87 Ninja 250r with only 5k on it and runs beautifully. My only problem is that I think it sounds a little soft for me with the dual stock mufflers. I decided to take one of the mufflers off on the left side and it sounds amazing. I know its not street legal to not have that on their, and also I know it makes the engine less efficient. But will it actually permanently damage my motor? I am planning on replacing the mufflers with aftermarket slip ons, but until then I luv the way it sounds and feels. But ill def put it back on if its gonna destroy my motor.

[Skippii]

Eh, it's probably not doing permanent. You might burn an exhaust valve.
It's a pretty obnoixious and stupid thing to do, though (intentionally irritating everyone around you at the expense of engine efficiency.)

[Momaru]

So, you left one muffler in place? If so, you're now running your cylinders at different exhaust pressures, which may cause some issues and uneven loading on them. I don't remember if there's a crossover for the pre-gen exhaust headers like there is for the new gen stock, but if there is, you're also likely blowing the majority of exhaust out the un-mufflered side now.

It's all about balance. I'd pull 'em both or leave 'em both.

If you're really in for the single-muffler look/sound, AreaP has a 2-to-1 (full) system for the pre-gens that may work for ya. Their other exhausts are nothing less than excellent and I can't remember hearing anything negative about the model for the older ninjas.