Originally Posted by ER70S-2
Those numbers are for the stock muffler
Stock Mufler Inlet:
I.D. = 1.4"
O.D. = 1.51"
Stock Muffler Outlet:
I.D. = 1.135"
O.D. = 1.265"
Years ago I made a midpipe for the DR using 1-1/2" O.D. exhaust tube. It slid inside the stock exhaust pipe with the stock gasket (by your ankle). It was a proper slip fit.
The midpipe from Kientec is 2" O.D. (on the bike now). At the front (ankle), since it uses the stock gasket, I think it is also 1-1/2" O.D. into the stock exhaust pipe.
So I'm guessing that you need to get from 1-1/2" O.D. at the front (exhaust pipe connection), to 2" O.D. to match the Hayabusa inlet. The second pipe in the photo.
Be back later to answer any more questions.
From Kientec: (wowie, big pic
Thank you so much! That just explained everything for me. I'm going to try and do this Thursday or Friday. I'll report back on this thread when complete.