This one is approximately 42mm on ID. I imagine someone knows for certain. Be sure to do your research to determine if this vintage part will work with your application as all sales are final and as is. Check out my other items!The item "MX EXHAUST PIPE NOS SKYWAY 1970'S SUZUKI TS TM ETC" is in sale since Saturday, June 5, 2021. This item is in the category "eBay Motors\Parts & Accessories\Motorcycle Parts\Exhausts & Exhaust Systems\Pipes". The seller is "mayerbrothers" and is located in Tucson, Arizona. This item can be shipped worldwide.