Made a billet exhaust flange

[Red Rider]

I've been searching for quite awhile for someone who makes a billet aluminum exhaust flange for 86-91 CR250R's. My '86 ATC250R has a '90 CR250 cylinder on it, and the exhaust flange is smaller than the ATC's. I like the billet flanges with the o-rings that are available for the ATC/TRX250R's, and I hear they work great for eliminating that disgusting, drippy, oily pipe syndrome. Well, lately it seems as though my motto is, "If nobody makes what I need, I need to make it myself."

I purchased a 10" x 4" x 1" bar of 6061 aluminum from a local metal supplier's remnant bin. It was way longer than I needed, but for $10, I now have a lot left over for whatever future fabrication projects that I may dream up.

Pic #1: I've just barely gotten started by cutting the hole for the outside diameter of the flange.

Pic #2: Now I've cut out the basic outline using a saber saw. It was amazing how easy it cut, considering the aluminum was 1" thick.

Pic #3: The external dimensions are just about complete. Just a bit of tedious measuring, turning down, & remeasuring to fine tune the final exterior dimensions. In this pic, I still need to widen the center exhaust outlet hole just a bit.

Pics #4 & 5: The completed product with "Viton high-temp" o-rings installed.

Not too bad, huh? Especially when you consider that I didn't use a lathe, or a milling machine. I only wish I had those tools to use! Still this was fairly easy using just a drill press & a saber saw.

[jeswinehart]

Very impressive to say the least !

john

[3WW Star-Yamahondaman]

WOW !!!! impressed indeed !!!!

[OldSchoolin86]

WOW !!!! impressed indeed !!!!

Me too...........

[Howdy]

That is a true artist at work. I am impressed!!
Howdy

[Mr. Sandman]

Wow, pretty impressive Red, so that's what you were doing ALL weekend. Do you think it'll be any faster?

Red Rider is a master fabricator by the way when it comes to billet aluminum parts and if he had the right tools and equipment he could really do some amazing stuff. Maybe I can talk him into making me a +4" aluminum swingarm!

[Jeb]

Great Work!

[Darius1502]

Incredible...man...start a business bro!!

That is talent...I have no idea how you did that without the proper tools...

I have seen some impressive stuff...but this is awesome!!

[New2ATC]

Nice. Its amazing what people are willing to do to get the trikes running again.. You have some talent there man.. I agree with darius on the business part..

[staceyl200]

Nice job !! but how did you put the "o" ring grooves in ?

[samster143]

Nice handywork!!

[Red Rider]

Thanks to everyone for all the kind words. Remember this youngsters, it's amazing what one can accomplish, when you put your mind to work. Also, stay in school, because school is cool! Oh, and don't do drugs becasue they make ya' goofy.

Nice job !! but how did you put the "o" ring grooves in ?

In pic #3, with the flange spinning in the drill press chuck, I carefully held up 2 hacksaw blades (2 blades laying flat against one another gave me the proper width of groove) and cut the grooves into the flange. Once I got the proper depth, I then used a small file to smooth out the grooves. It worked great.

Do you think it'll be any faster? Maybe I can talk him into making me a +4" aluminum swingarm!

The aluminum flange is 2 oz. lighter than the original, so yes it should be faster. I would gladly make a +3" alloominium (as the english Junk Yard Wars stars say) swingarm, but +4" would be way too difficult & complex for my abilities, sorry.

[N5HNY]

I know everybody already said this.......

But your workmanship is outstanding !!!!!

It just goes to show what you can do with a few tools and the will to do it.

Braaaaavo.

[Billy Golightly]

How exactly did you make the flat flange area apart from the round part where the pipe goes on? I know you said you didn't use a mill but did you have a rotary table off of a mill or a rotatable vice? I dont see how its possible to keep the mounting flange and the round part the the pipe goes over so smooth and true without one...

[Red Rider]

I guess I should have taken some pics of the actual work being done. To cut the flat flange area nice & straight, I took the piece from pic #2 and bolted it to a flat board through the center hole. Then I centered the board on the drill press table, and clamped it down. I put a 4" fiber cutoff wheel into the drill press chuck & raised the table to the proper cutting height. I left the table clamp loose enough so I could spin the table around, allowing the cutoff wheel to gradually cut around the circumference of the flange. When the front side was done, I then had to flip the flange over & do the same to the back side, leaving the little lip that mates to the cylinder. It took about 30 minutes to cut each side, but it made beautiful, straight, & square cuts.