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Discussion Starter #1
Guys, I spent a few years machining and welding prototype frames/ suspension linkages/ swingarms in the mountainbike industry and I'm finding myself wondering if there is'nt a need for someone to weld/ brace frames, make the occasional set of clip-ons (c'mon those pro-flo's are expensive) or pipes.... Does anyone offer welding services to the racing community in the ny area? Or should I start messing around? Well, just started tearing the 350 down so I'm gonna be f-in' around anyhow.
 

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hey rosko,

how about fabricating a chrome-moly cb350 frame. it could be a very cool project and you could copy a tubular sl frame. those stock frames are lighter that the cb ones and dont have the pressed backbone. graft the headstock on and fab a better/stronger swingarm (sl's were notoriously thin and weak). shit, what could be the weight savings? hell, i'd buy one if the price was reasonable and maybe then would have the cb350 stocker that could place perhaps first or second overall at loudon. i'd love to hear your or anyone else's thoughts.

tex
 

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I think the CB350 is sorely in need of a custom frame, could probably build one 20 lbs lighter and stronger to boot.

I've done a couple of complete chassis...I'd want $700-1000 for one. The first one is the hard one. I'm NOT saying I'd make one. I'm saying if I did that's the minimum I'd want to do it. I probably have 100 hours in the chassis I made for Mary's little Honda. Course it was the first one I'd ever done. Turk built the entire chassis for his Bulto.

I'd love to see someone making a nice race chassis for the 350. Would breath some new life into the old beasts.
JohnnyB
 

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Discussion Starter #4
Well tex I gotta say... exactly what I was thinking. I have a great hook-up for 4130, The jigs would be pretty simple especially for the swingarm... Just need a frame to copy or.. need to make an adjustable jig and work from a drawing. It starts to get tricky, what would be the best head tube angle for a 350 with say a 550 fork? Ride height and fork travel all come into it. I'd be interested to see one of those 450 frames that henning/ hanson has. Well, I guess it comes down to: what would you change? Obviously just switching to 4130 is an improvement but, as they say, the sky is the limit. (or at least theoretically)
 

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would a cb350 motor in a featherbead frame be legal? if so, why f around. i guess they are a pretty sweet chassis (minus manx power and all). i wonder if i could convince my friend to lend me his?

tex

p.s.- if you serious on the sl idea i'll put out the feelers on a donor frame. o.k., anyone have an sl frame?
 

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id kill to see someone making some kcikass aftermarket frames for those cb350's frank camilliere had one he sent me pictures of he was working on and i didnt even look like a cb350 anymore. really really cool. id even save some $$$ for one if they were good. i know i cant afford a drixton though. tim stancil ran his 350 in a trackmaster frame. i thought that was pretty cool. but they arent supposed to be great roadrace frames. with his backround though im sure it was more than perfect for him.

anyway...

jc
 

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tex, do yourself a favour and use the 4k on a van first. im sure toms van is still sitting there. all alone. waiting to haul race bikes.

jc
 

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Discussion Starter #10
Does Camilliere still have a website? I tried the link and no go.

Tex, I'm in the process of setting up a new workshop... Once thats done I'm down to UPGRADE an SL frame...

and vans... I've got a 20 yr. old conversion with curtains and blinds!! The damn thing makes me look so creepy I can't go within 20 miles of a school....

Just kidding. Really.
 

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I've got a complete SL frame and swingarm in my basement that I'd be happy to lend out for the project.

Not a huge fan of the pressed steel stock cb frame. But I'm picturing the Honda chassis guys at the factory in '71 "Hey- this upper pressed and spot welded frame tube is like a monocoque."
"dude you said 'coque'"
High fives all around

bfd
 

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there are also pics of franks frames in the recent history of ducati racing book thats out with frank credited.

jc
 

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quote:
Yeah, I like the design of the Yetman. He used superlight thinwalled tubing...all triangulated. Pretty trick structurally.
Gonna try'n find that Duc book + have a browse.
I was over at his shop a few weeks ago, he had a little Yamaha roadrace frame he was working on. Thing of beauty. Everything was triangulated with tubing.

He does excelent work. And he brazes all the joints instead of welding them. Less stress on the tubing, less distortion than welding.
And plenty strong.
 

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I've gone to TIG welding everything with Silcon Bronze rod...it's kind of halfway between welding and brazing. Techincally it's TIG Brazing because there is no need to melt the parent metal. But this type of rod tends to penetrate the surface of the parent metal and form a very strong bond. It's what you see used on a lot of english frames with those very cool gold colored smooth welds. Stuff is incrediably easy to work with and will bridge gaps extremely well. It was originally intended for "cosmetic" welding. But in our case with a 90,000 psi strength it's more than suitable for frames. When torch brazing I use a Nickle Silver rod, expensive, but like the Silcon Bronze it's easy to use and strong.
JohnnyB
 

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quote:
I've gone to TIG welding everything with Silcon Bronze rod...it's kind of halfway between welding and brazing. Techincally it's TIG Brazing because there is no need to melt the parent metal.
One day I'll have a garage/shop big enough to have a nice tubing bender, drill press, small lathe, and a tig welder.

Well, maybe not. I have nothing in the way of fabrication skills.

But I'd love to build a custom frame for my CB450 streetbike. Some Ducati-esc, with a nice trellis frame. For no other reason that it'd look cool.
 

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Looking cool was the primary reason I built the trellis style frame for Mary's little 50cc. Would have been much easier to do something conventional. But...never get tired of people coming by and gawking at that chassis.

I just got up from the shop...spent four hours TIG welding on Hiroshi's new 200gp bike. What a freakin pain. Another piece of crap put together by those numb nuts on the west coast...the whole Eurospares gang. It's like they are bunch of nerds that sit around thinking about theories but never actually race anything. Freakin bike had frame braces that prevented you from taking out the engine mounting bolts, had non-replaceable steel pegs all welded up to the lever pivots, someonebody's goofy idea of frame bracing, steel seat mounting, various other parts that didn't work or didn't fit, twin coils when it only needs one, piston with a deck height about .020" above the cylinder deck...compensated for with a .080" thick head gaskets, tires big enough for a 500cc.
Damn..I should have never taken this job...or should have never quoted before I knew what a piece of crap this thing was. Would have been easier to start from scratch with a bare OEM frame.

Anyway....about four hours of work on it every day for the next month and I might get it done it time. I'll end up making about $4 an hour.
JohnnyB
 

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Hey Johnny:

Can you give me a heads up with the sl350 carbs on the 175 as to whether stock jetting is a good start or should I go right out and get some biggah ones? Scott

jeez i'm sorry i brought up that rapture thing on the skulls. crazy dialogue.
 
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