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General Category >> Technical >> New bike plans, no money for tubing
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Message started by Opus the Poet on Feb 17^th, 2012, 12:48am

Title: New bike plans, no money for tubing
Post by Opus the Poet on Feb 17^th, 2012, 12:48am

I just got the PDF for a FWD low-racer made from a mix of recycled BSO and round and rectangular tubing, but I ain't got the $$ for the rectangular tubing. Frustration! I can't even beg for scraps from my usual tubing supplier because the size in the call-out is both a thinner gauge than he carries and a much more expensive alloy than he usually carries. The BOM calls for .060 wall 4130, and the thinnest my usual supplier has is .120 wall 1012, a much softer alloy. I could use the .120 for the brackets (the plans call for .120 for making the jigs and most of the brackets used on the bike). The BOM also calls for a hunk of 1" .060 or .065 wall 4130 for the steer tube, I can get that local and it won't cost too much. But that rectangular 4130...

Like I said, frustrating...

Title: Re: New bike plans, no money for tubing
Post by rmillay on Feb 17^th, 2012, 8:46am

Opus, what's the advantage of rectangular tubing, besides more weight?

Title: Re: New bike plans, no money for tubing
Post by Opus the Poet on Feb 19^th, 2012, 9:00pm

Rectangular tubing is self-jigging and has a bit more beaming strength. From reading the instructions the beaming strength is slightly excessive for this bike (the instructions advise cutting lightening holes in the long sides of the box section). Personally I would just go with a thinner wall tubing instead of cutting holes in the tubing but .060 or .065 is hard enough to find, .035 is almost impossible. I can weld that thin a section no problem, finding it, big problem.

Title: Re: New bike plans, no money for tubing
Post by Opus the Poet on Feb 21^st, 2012, 3:31pm

I should have mentioned that the plans I got are to the F'lowroller FWD low racerhttp://i19.photobucket.com/albums/b157/rohorn/daddio1.jpg

I plan on making just one slight modification, using a claw adapter to mount a derailler, and installing a brake bridge for a front caliper brake.

Title: Re: New bike plans, no money for tubing
Post by Opus the Poet on Feb 21^st, 2012, 3:46pm

The original prototype bikehttp://bikerodnkustom3.homestead.com/files/img10A.jpg

http://bikerodnkustom3.homestead.com/files/img18a.jpg

http://bikerodnkustom3.homestead.com/files/img11A.jpg

Title: Re: New bike plans, no money for tubing
Post by power_bent on Feb 24^th, 2012, 12:02pm

Now thats a cool looking bike. I have a cruiser that I can use????

Title: Re: New bike plans, no money for tubing
Post by Lrodshy57 on Apr 10^th, 2012, 2:51pm

opus,
Have you ever tried making the original rbent bike called the 'ground hugger' feature in popular Science?
btw where at be da helmet on dat little girl?

Title: Re: New bike plans, no money for tubing
Post by FlyingLaZBoy on Apr 11^th, 2012, 7:22pm

How does steering function -- tilting the front wheel (and cranks) ???

Title: Re: New bike plans, no money for tubing
Post by Tom Nuchols on Apr 11^th, 2012, 9:22pm

The design makes me think that I would have grease covered right calf after a ride.
Tom [smiley=grin.gif]

Title: Re: New bike plans, no money for tubing
Post by johnnybent on Apr 11^th, 2012, 9:58pm

Tom Nuchols wrote:

The design makes me think that I would have grease covered right calf after a ride.
Tom [smiley=grin.gif]

You've never seen a rider on an xstream?

Title: Re: New bike plans, no money for tubing
Post by FlyingLaZBoy on Apr 12^th, 2012, 7:32pm

johnnybent wrote:

[quote author=Tom Nuchols link=1329461329/0#8 date=1334197359]The design makes me think that I would have grease covered right calf after a ride.
Tom [smiley=grin.gif]

You've never seen a rider on an xstream? [/quote]

XStream? Heck, the StratusXP was more of a grease-depositor than the XS is....

Title: Re: New bike plans, no money for tubing
Post by JimFPU on Apr 12^th, 2012, 9:23pm

I don't have any grease problems. Should I? [smiley=shrug.gif]

Title: Re: New bike plans, no money for tubing
Post by Tom Nuchols on Apr 12^th, 2012, 9:42pm

I have home built tour easy clone that does a very good job of making my calf greasy. I have not seen an ex Stream, but I have seen Rans Stratus.
Tom [smiley=grin.gif]

Title: Re: New bike plans, no money for tubing
Post by rmillay on Apr 13^th, 2012, 7:34pm

I'll put my Musashi up against any bike for greasing up a leg. It made me clean the thing, finally! ::)

Title: Re: New bike plans, no money for tubing
Post by JimFPU on Apr 13^th, 2012, 9:52pm

I guess i'm doing something wrong then...

Title: Re: New bike plans, no money for tubing
Post by Opus the Poet on Apr 15^th, 2012, 10:37pm

FlyingLaZBoy wrote:

How does steering function -- tilting the front wheel (and cranks) ???

Yes, the technical classification is Rear-mount Moving Bottom Bracket.

Title: Re: New bike plans, no money for tubing
Post by Opus the Poet on Jun 5^th, 2012, 9:52pm

I may be getting the $$ to build the bike from my Dad, as a "Thank You" for spending over 6 weeks away from home and living on microwaved food.

Title: Re: New bike plans, no money for tubing
Post by Opus the Poet on Jun 5^th, 2012, 10:02pm

Tom Nuchols wrote:

The design makes me think that I would have grease covered right calf after a ride.
Tom [smiley=grin.gif]

If you look at the picture of the designer riding with his daughter you can see that most of the chain is away from the rider and only the part around the chainwheel is close to the rider, but you would need to get your calf around the crank to make contact. About the only chance to get greasy would be making a sharp left turn with full right leg extension.