Cast Aluminum dirtbike/quad conversion swingarm

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I did this last year for a friend, was digging around and figured I'd post it. What we're looking at here is the front half from a 1987 Honda CR500 dirt bike swingarm (Since thats the frame and motor combination its going on) and the rear half is from a late model Honda TRX450R. My friend built a three-wheeler, so he needed the different part of the swingarm for the carrier and all that mess. He cut and aligned things up as best as he could and then built a bed frame jig (hey, it worked) and shipped on down here to me to weld up. Obviously the arms were each a completely different design and shape. Matching them up was pretty difficult, he did a good job for what he had to work with. A little bit more gap in the areas then I would have preferred, but I made it work. Next one I might build from scratch, we'll see. This one has had a lot of use on it and hasn't had any problem, I check up on it regularly
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Reply:And here it is finished:Looks like the order of the above pictures got a little mixed up...oh well.
Reply:It's a shame when a perfectly good dirt bike gets cut up to build a quad or trike.
Reply:Nice close up pics. What welder and wire (4043, 5356)?? I'm guessing MIG but I want to know anyway.9-11-2001......We Will Never ForgetRetired desk jockey. Hobby weldor with a little training. Craftsman O/A---Flat, Vert, Ovhd, Horz. Miller Syncrowave 250
Reply:Nice job. Nothing wrong with the bed frame metal, its cheap...BobBob WrightSalem, Ohio  Birthplace of the Silver & Deming Drillhttp://groups.yahoo.com/group/southbend10k/http://groups.yahoo.com/group/sawking/1999 Miller MM185 w/ Miller 185 Spoolmate spoolgun
Reply:Miller Dialarc HF TIG (300amp model) running 1/8 green band tungsten and 1/8th 4043 filler rod. I lost the pics I had of it when it was first put together before it had all the weld on it, my friends gonna email em to me and I'll re-post so you guys can see how it started out.Hey 76GMC1500, this was actually a scrap yard build by my friend. He got the motor and frame from a yard and pretty much pieced all the rest of it together. Its a good machine, hes still working out some issues with it but its a monster for sure. I've got a CR500 powered ATC250R that I setup for short track racing, rebuilt the entire bottom engine cradle and a few other odds and ends on.
Reply:BillyGoat:Thanks for the answers.Dang, TIG; I blew that guess. Ok, water cooled torch? (1/8 tungsten + 1/8 filler = HOT)IF you answer aircooled, #26?TIA, Craig9-11-2001......We Will Never ForgetRetired desk jockey. Hobby weldor with a little training. Craftsman O/A---Flat, Vert, Ovhd, Horz. Miller Syncrowave 250
Reply:Oh yeah, definitely water cooled torch. Some weldcraft model, rated at 250amps I think (I had it right in that neighboorhood, the coolant line got warm enough that I decided to move it away from my lap early on) I had some really thick gloves on and I still had to stop and wait for things to cool down after a couple of passes, it was definitely hot. I'm sure it'd be possible with an aircooled torch, but you'd be one hardcore mofo IMO
Reply:Welds look nice, and fit up looks like it'll work just fine. Ride er hard!Miller Thunderbolt 225Millermatic 130 XPLincoln HD 100 Forney C-5bt Arc welderPlasma Cutter Gianteach Cut40ACent Machinery Bandsaw Cent Machinery 16Speed Drill PressChicago Electric 130amp tig/90 ArcHobart 190 Mig spoolgun ready
Reply:Pretty nice welds and strong for sure too. What kind of cleaning process did you use?How much time did it take you?My Babies: HF Drill pressHF Pipe Bender3   4.5" Black and Decker angle grindersLincoln Electric PROMIG 175that´s it!
Reply:Thanks! The Honda parts that are casted normally weld pretty well as long as their not engine cases that has been basked and baked in oil for 20 years. I first beveled down all the joints as best as I could with a rotary burr type cutter (1/4 shaft size). I found out a neat little trick, if you dip the cutter in a little tub of mothers aluminum polish, it really helps to keep that aluminum from gobbing and gumming up on the cutter itself. AND, it makes a pretty neat smooth finish, almost like it was milled out. Thats what some of the little white smears around the jig and on other parts of the arm is.From there, I run over the area as best as I can with either an 80 grit sanding flapper wheel, or I use one of those little flat round abrasive pads that are red, I really don't know what their called. Its sort of the same material that a scour pad for washing dishes is made out, but just more aggressive and a little tougher. After that, I pretty much just wipe down with a bit of acetone or paint thinner using a blue shop towel, wait for it to dry. I'm usually pretty careful to not let me bare hands or especially the gloves touch it in the areas that have been prepared either.
Reply:It all look really good to me. I'd love to see what it turns into. Looks like it has a lot of fun in the making and should create a lot of fun in the end."One of the things we have to be thankful for is that we don't get as much government as we pay for." (Charles Kettering)Mitch 180 (NZ)Lincoln SAM-400-220 + ?-400 Fordson Major + 2 x Tractapac Humber 80 + Procut 40 PlasmaMiller Spectrum 375
Reply:Heres the pics of how it started out.