Pillsbury that is a great find. The 2 ND pipe looks to be a Yamaha Enduro. Really nicely made. Thanks.

I called Gary to see about a pipe. He has a 78 Yamaha Dt400.

I'm not Rich but I know Gary builds to fit anything. He also has quite a few rolling frames so he is able to fit them in his shop.
Tell him Tom from AZ sent you. Here is some of his up pipes

I will tell him Tom. Those pipes are so nice. Anyone know if dt250/400 for 77/78 are the same. I think someone here had both to compare, that they were.

You will like Gary He is a nice guy

Rich

Sand the exhaust port. This reduces the surface area of the port so we have less heat going into it. I finished mine to 400 grit. What really works is making a flap wheel of sorts using a 3/8 inch dia wooden dal in a drill. Cut a 1 1/4 inch slit on the end and feed your paper into it. Avoid resizing the port tunnel particularly the top. We don't need a larger tunnel or outlet to the pipe. If you are brave angle the stick to the sides of the window of the port and work that and the radius to the top. I have heard this will give a little kick to the power. Do at your own risk. Just work the area of the port above where the transfers open and the radius in the left/right top corners. Feather into the rest of the port. I think .5 mm is good, as may be a little to much could be detrimental, or a little goes along ways. We don't want to lose any low end torque at all. We have not ported this cylinder or done any other mods. Each item stand alone. so what the heck. A generous bevel is good. No need to hog the tunnel to match. Afterward, make sure to put a 30 degree bevel on the port edge so the rings will not catch. .75mm at the top, then going next to nothing at the sides. That's how I did mine.

I dont mean to be offensive but that work really wont amount to anything that will be felt . Just being honest

Rich

By gravel crew from Japan

Did you change any of the jets , if so which and how much? Before and after .

I trust in your input Rich. Thank you.