My first aluminum project - s'alright

My motorcycle has been popping a lot on deceleration lately (probably because I put a short pipe on it). One of the fixes I found was to take out the secondary air injection system but my bike is old enough that nobody sells plates to cap off the reed valves anymore so I thought I’d try making my own. They turned out great except that I gouged the surface pretty badly during a parallel finishing pass using a 1/8 end mill. Note to others trying aluminum for the first time - Tighten the v-wheels frequently! I was getting a lot of chatter which I figured was normal for metal but once I gouged that plates it occurred to me to check the rigidity of the mill. It was pretty loose. Anyway, the parts are installed deep within the bike where only a mechanic and I might ever see them so no biggee. Also, the bike runs like new again now.

I would post my settings but I wasn’t getting good chips. Should I carve deeper or faster if the bit is rolling up a curly string of aluminum instead of throwing chips?

First I made wooden prototypes (the urge to coat and use these was pretty strong).

Here’s a pic of the finished parts. The surface is a lot smoother than it looks in the pics except the gouges from left to right that are probably more than .020 deep.

and here they are installed in the bike where nobody will ever see them. I’ll have to improve the quality a bit before I start making parts that are visible.


I suggest you increase your feed rate a little bit, and most importantly, use a cutting fluid such as Tap magic for Aluminum.
I’ve been making aluminum and brass stamping dies with my Nomad for a while now, and had your problem in the beginning.

If the machine seems to be struggling or bogging down, reduce the cut depth a bit.

Your parts are sweet! You should refine the design, and sell them on Etsy or something, as I’m sure you are not the only person to have that problem :slight_smile:

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I appreciate the advise. I’ll try increasing the feed rate and if that doesn’t help I’ll reduce the depth. I was using Tap Magic. I think it would have turned out a lot better if I’d have kept the v-wheels tight for the whole job.


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Smog block offs did wonders for the decel “pops” I had on my old R6 that had a straight pipe, but what really made it shine was a proper tune (ECU reflash and a Power Commander). The parts look good, you’re lucky that the smog injection is right on top, on the R6 I had to fiddle around where I could barely fit one hand. 3 cylinders? Triumph? I have a Street Triple R, love 3 cylinder low end torque, plus some of the high rev benefits of an i4. I wish I had my SO3 back when I was doing my modding, but sadly now my bike sits covered in chips. It’s really cool to be able to take an idea and just make it without paying shipping and waiting for the mail to get delivered just so you can go riding. Really cool work!




I re-flashed it too. I could have kept the plumbing in place but Im going to use the space to rearrange some things. I’d like to build a single seat instead of the double it comes with but that means moving a bunch of relays and fuses. It’s a 2005 Speed Triple (good guess).


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