I put a muffler that fits 97 Honda Civic and it really quieted the vertical exhaust that I put on my BX. Not a problem and it's been on for at least 5yrs. I do have a support brace. <img src="http://www.tractorbynet.com/forums/attachment.php?attachmentid=523273"/>
The honda muffler inlet and outlet is 1 1/2" inside. Second one down here 87 1987 Honda Civic Muffler - Exhaust - Walker - PartsGeek