The one on my every day driver wound up getting smashed bad on the two bottom tubes, and on top of that there are several small holes rusted through the same tubes, from sitting on a bike out in the weather for 15 years. So I pulled out another parts bike and the V&H pipe on it looked pretty good, then I checked it out on the bottom, and it has smashed tubes to, way bad but no rust. I started checking out the prebent tubes available for header fabrication, and I was about to make the plunge and tig weld in new pipes, then I got an idea.
I was thinking if I had a tool I could drive up in the collector end, I could reform the pipes to a degree. So I ordered a 1 1/4 inch steel ball, it is the hardened type made for bearings, big bearings. I fired up the tig welder and welded it to a 2 foot long piece of 5/16 mild steel rod. The bearing didn't want to take the weld, but at about 180 amps on the miller Synchrowave, and cranking up the shielding gas it cooperated. I left a huge fillet to reinforce it to the rod.
Now time to try it. I didn't count on there being a divider plate in the collector, but there is. With a little bending it moves over to the side enough for me to get my ball tool in. I coated the ball with grease and began to drive it up into the tubes. Because the tubes are not straight the 5/16 steel rod bent a bit so that the ball could go down the tube. It really opened up the tube and reshaped it without damaging the tube at all. I thought it would be a nightmare to get out, but I clamped a set of vise grips on it and tapped the vice gripe with a hammer and it came right out. Then I did the second tube and it worked just as well, after tweaking the internal baffle a bit.
The ball acted like a die, and reformed the tube nicely. Now it isnt perfect, because the ball was purposely a hundred and twenty thousandths under sized. The ID of the tube is about 1.37" and the ball 1.25". most header tubes are a little smaller where they merge into the collector because of the weld beads, and other deformations. I thought I would be lucky to get a 1.25 inch ball in, and it went in pretty easy, one tube was a little tougher to get the ball into, but not bad. The results are pretty decent, and the tubes look nice, and will flow well again. The ball cost $8 with shipping, and the 5/16 rod was a scrap that I already had. Fixing the tubes otherwise would have been either expensive, and time consuming, or impossible. The only thing missing was the AC DC song about big balls.
Comment