Motorcycle frame article, what do you experienced guys think of this?

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I ran across this video/article today and I wanted all your honest opinions on what's going on here.http://www.stuntbums.com/creatingstuntbikesAside from the part where he's tacking up the fixture without a hood.
Reply:My hunch is that the type of guy who would build a motorcycle frame based on info gleaned from the web is also the type of guy who would think that having a motorcycle that could fall apart at any second is just part of the fun.Tim
Reply:From what I gather, he is building the jig from the original frame and will build the new frame off of that jig right?So if he has to cut off the original frame, how is he planning on removing the new frame once built?Did I miss something completely there?Tom...Canox C-SW 250 (Rebadged Syncrowave 250)
Reply:Originally Posted by Tom17From what I gather, he is building the jig from the original frame and will build the new frame off of that jig right?So if he has to cut off the original frame, how is he planning on removing the new frame once built?Did I miss something completely there?Tom...
Reply:Looks like the bike is going to be used a stunter - not the brightest bunch in the World to start with.If so, the bike probably won't see the street / track with any high speeds. So frame failures might not result in a much of an injury to the rider.I like his "Squint Goggles" that he tacks the jig to the table with. Nice.
Reply:He's a mess.  I hope noone gets hurt..Buy American, or don't whine when you end up on the bread line.
Reply:Oh look, someone got hurt.  Not even built yet..Buy American, or don't whine when you end up on the bread line.
Reply:As soon as he cuts a frame tab lose from the rest of the structure it's gonna move from it's original location, hopefully he'll notice this and re-think. From the start it's not clear the builder knows where things should go (good dimensions, angles etc.). If he did it's just best to get the parts together and just "loft" the structure.When you build something like this, it is nearly impossible to repeat a success.Matt
Reply:Matt, thanks for the reply. Any insight as to how motorcycle frame builders manage repeatable results?
Reply:All I can say is good luck to the guy.  Stunting a sportbike is subjecting the components to stress that it was never designed to handle.  Its a testament to their quality and engineering that they handle as much abuse as they do.  Even the factories have issues with a frame from time to time, ala- GSXR's from a few years back.  Not so much a frame problem as a welding problem, but still.
Reply:Originally Posted by JoshDAll I can say is good luck to the guy.  Stunting a sportbike is subjecting the components to stress that it was never designed to handle.  Its a testament to their quality and engineering that they handle as much abuse as they do.  Even the factories have issues with a frame from time to time, ala- GSXR's from a few years back.  Not so much a frame problem as a welding problem, but still.
Reply:Here are some pics I found that show what happened to the frames.  From the little bit I've read about it, it seems like they are done by machine, someone didn't get the machine set right, and there is no penetration.  http://www.sportbikes.net/forums/spo...ssue-pics.htmlhttp://www.sportbikes.net/forums/gen...-breaking.html
Reply:Originally Posted by TaidenMatt, thanks for the reply. Any insight as to how motorcycle frame builders manage repeatable results?
Reply:My only comment on building  / modifying bike frames is - don't expect an improvement in performance, and if you are trying to push the performance envelope, don't do it at all. Typically, most end users aren't smarter than a team of factory engineers with a substantial R & D budget.If you have the skills and don't mind being a test pilot (and are smart enough to realize the limits), building frames would be great fun.As I was watching the video, I thought to myself:1) this guy doesn't seem to be exceptionally smart (that is a first impression, could easily be wrong)2) Oh NO, he's welding directly onto his welding table (I know lots of people do this. I don't)3) those tabs (the ones welded on the table) to bolt the frame to are way too light. A frame jig should be much much stiffer. The frame will spring a noticeable amount with the first cut. Dimensions will be way out by the time he is done, and will most likely negatively impact handling.JasonXMT 350 MPA Dynasty 280DXSuitcase 8RC / OptimaSpoolmatic 30AThermco Ar / C02 mixerAssorted O/A gear
Reply:Another interesting website on frame design / building:http://www.eurospares.com/frame.htmJasonXMT 350 MPA Dynasty 280DXSuitcase 8RC / OptimaSpoolmatic 30AThermco Ar / C02 mixerAssorted O/A gear
Reply:Here's some ideas for proper fixturing. This shop uses a modular fixturing (Bluco) for their applications. I'm sure its cost prohibitive for most, but gives you ideas for building something yourself - http://www.ncad.com/welding_fabrication_r1.htmlThere is even a used setup for sale here on WW - http://weldingweb.com/vbb/showthread.php?t=47768This next guy builds car stuff, but his site is uber interesting - http://www.davepropst.com/Overview.htmJasonPS one more - http://www.bluco.com/applications/ve...cle_frame.htmlLast edited by BCRD; 12-22-2010 at 11:08 AM.XMT 350 MPA Dynasty 280DXSuitcase 8RC / OptimaSpoolmatic 30AThermco Ar / C02 mixerAssorted O/A gear
Reply:Originally Posted by TaidenMatt, thanks for the reply. Any insight as to how motorcycle frame builders manage repeatable results?
Reply:OCC don't use no jigs, Paul jr. just sticks it on the table and tigs it...Then Paul Sr. come in and fumes off, then they sell it for 30-50 thous. Actually Paul Sr. doesn't know his a## from a hole in the ground.....(don't tell him i said that)
Reply:Everyone has their first. First time weld. First welding cart. First welder. First time motorcycle frame. You've got to start somewhere.This guy may have the right idea. He is using the old frame as a guide to build a jig to replicate the original. It looks like he has some pretty good equipment around so he may have the ability to build a bike frame. To say the bike will fall apart is a bit pre-mature as there is no new frame built yet. The next video, if there is one, will probably show if his efforts are worth it. Who knows if he is going to use 4130 or just some crappy Chinese steel. He may be a crappy weldor.....who knows.....but he may be a good one too. We will have to wait and see.I'd like to see how it turns out as I am going to build an enclosed motorcycle with A/C and heat. It will involve tigging, migging, metalworking and mechanics. Thanks for the link as it will be interesting to see the end result.
Reply:Originally Posted by 1awert1OCC don't use no jigs, Paul jr. just sticks it on the table and tigs it...Then Paul Sr. come in and fumes off, then they sell it for 30-50 thous. Actually Paul Sr. doesn't know his a## from a hole in the ground.....(don't tell him i said that)
Reply:Originally Posted by JoshDHere are some pics I found that show what happened to the frames.  From the little bit I've read about it, it seems like they are done by machine, someone didn't get the machine set right, and there is no penetration.  http://www.sportbikes.net/forums/spo...ssue-pics.htmlhttp://www.sportbikes.net/forums/gen...-breaking.html