Dave,

I'd look into hydroforming the pipes... would give you more of a "stamped steel" look and from what I've read can be done fairly easily with a standard pressure washer as the pressure source. Those pipes might be very easy since the expansion chamber looks pretty straight after the head pipe. (I've read that hydroforming gets tricky when forming curved pipes.)

You might even be able to "crimp" the seams and make them look perfect!

Keep up the great work!

Hope I get to see it in person someday.

Mark....I had been contemplating hydroforming them also !

It could be a very slick way of doing it ?

Another way to prototype the pipes is to spin them,you can make several on a lathe in a day.Once you get your flow right then you can transfer the dimensions to your hydro pattern or traditional sectional pattern.The header curve is no easier but maybe talk to a muffler shop to bend it for you.But maybe you may like a light muffler?

Bluntz very interesting idea.....

thanks for the post !

Hi Mark,

Are you talking about something like this ?





It seems like it could be a time consuming process....
maybe making them out of stainless ????

Why don't I send someone here the dimensions I need and you make them for me ?

The second video is hilarious but....... really cool. You can do it Dave.

Has anyone here tried hydroforming ????


Anyone else have opinions or knowledge on the subject ?



The Ascots pipe do lend themselves to that hydroformed look....

Decided to pull out the Ascot's TD1 cylinders and clean them up a bit.







Things were even more simple back then...notice the single transfer on each side of the bore.
This was referred to as a 3 port design...Yamaha being a leader in two stroke technology introduced the 5 port layout design sometime around 1965 or 1966 ?

Yamaha appears to have standardized things very early ...
as the intake stud spacing is the same at the AT/CT.

I like how the intake ports were cast...nice straight path into the crankcase





The exhaust ports have lots of area to work with
I did a quick "knockdown" the major casting flaws
and will be keeping the port timing stock.

No porting....just polish !




I haven't checked the piston clearances on either jug yet.

What's the actual cc's of each cylinder and how much HP rating in stock tune?