Crazyhorse's How to stretch a StingRay Chopper conversion into a XXL Chopper!

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GenMinion

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Sep 19, 2020
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Are you saying 2 1/2"x 1 1/2" 16/14ga steel tubing is a snug fit over the Schwinn factory oval bottom tube?
If my measurements are correct, though it may require crushing/cutting/forming the Factory oval to fit inside the Rectangle tube, as the Oval is JUST under 2.5"x1.5" by like .240" or so, so the 16/14ga should work, maybe even 11ga or .120 should do, but won't know until I can try to source the rectangular tube locally (Not fond of spending almost $30 for steel just to take an irreversible chance). Far as the down tube and top tube are concerned, was thinking of getting the 1.75+ tube, find a size that fits snug into that, cut the 1.75 to length, drill about 4-6 holes into each end in an X pattern around the ends,cut off about 4-6 inches of the smaller tube, slot it halfway into both ends of the 1.75 tube, weld them together at the holes. That way the fill-in tube has extra support at the joints, then finish welding together. Kinda hard to explain (never was good with explanations, was always the hands on type), so once I( get my project underway, I'll upload pictures on ym progress as well as any road bumps I might run into.
 
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GenMinion

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MadMadRonin

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Mar 13, 2020
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Oh absolutely, if you can get it local, go for it by all means. I'm without the capability to drive and live about 45 minutes from the nearest place to get metal.
 

Larry85326

New Member
Aug 21, 2020
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Buckeye Az,
New here , but I have started the same idea and I found that a donor bike is cheapest for the metal. But if your looking to keep that same oval shape a vise worked for me. Just stand the tube up and slowly sqweeeze the tube and letting off a bit then back some more until you get the same shape. It took a few texts to get the correct shape but I did get it right. You should however take a marker or prick your finger and use your blood. ( Not recommended) and draw a line the length of the tube as so to get the ovals place in the same position.
I do however think you guys do rock at this . I wish I knew then what I have read now. The rig and rotisserie would have saved me countless hours of frustrations and cus words. I really how that this post gos on and more picks. I know it's not the first but I did however after all said and done did make mine in to a trike with a donor OCC bike a friend for lack of better words BUTCHERED . But the parts I did save he did not. I'll post pics once I figure out how to do such. The trike axel did make it so much easier to mount a 212 cc predictor on it.
Again you guys please keep up your work and hope to continue see more posts here. Thank you for reading along with my ramblings. Best of luck.
 

motorhedfred

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Jul 31, 2009
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I'm getting ready to cut up and stretch one of my OCC Stingrays. Since I'm borrowing a welder, I want to have everything I'll need at hand. I'm using 1.75" OD .120 wall mild steel to lengthen the top tube so a 1.625 OD slug will be a good snug fit with a little heat and persuasion.

The only question is the inside diameter of the factory top tube. I can't measure it without cutting it first. Does anyone know the ID or wall thickness of the factory Schwinn top tube?
 

HeavyMetal74

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Sep 3, 2023
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I'm gonna do this to my OCC Schwinn.
Great idea.
Where's the pics for the frame building jig?
The link goes nowhere.
Maybe needs fixed
 

Wevil Kenevil

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Mar 4, 2022
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Sack a tomatoes California
This is how I Stretch / Convert most styles of StingRay Choppers or Clone OCC Chopper into a Schwinn XL Chopper or the Schwinn XXL Chopper style build.

Here's a Parts & Tools list that you'll need to get started:

Tools and Equipment:

For cutting the frame up use a hack saw, reciprocating saw ( Sawzall ), angle grinder, or steel chopsaw for the straightest cut.

For welding the frame back together, a welding shop or your own personal welder.

I use 1-3/4" round steel tubing for the top tube, and downtube from headtube.

I'd suggest sleeving slightly smaller steel tubing inside the 1-3/4" steel tubing for extra strength for the new extended steel tubing that you'll be using on the top tube which runs from the headtube to the rear triangle and the for the new extended tubing which you'll be using on the steel tube which runs from the headtube to the bottom bracket also known to some builders as the pedalcrank.

I use 1-1/2" X 4" X 16-gauge rectangular steel tubing for the bottom tube.

You can build this Stretched Chopper as an XL Chopper with a 22" bottom tube, or you can build this Stretched Chopper as an XXL Chopper with a 30" bottom tube.

Notice: Remember your leg length should determine the amount of Stretch you decide on, 5-7-inches to 6-feet tall you'd want to only add a 22-inch bottom tube. 6-feet or taller go for the XXL Stretch Chopper with bottom tube measurement of 30-inches.


You also need 2 stock 20-inch StingRay or OCC Style Chopper Bicycles to chop for your build. Or just one if you can source the 1-3/4" round steel tubing.

I prefer using the 1-1/2" X 4" X 16-Gauge Rectangular Steel Tubing for the bottom tube so that I can easily add a Honda crf50 or Pitbike, and or kids ATV ( 49cc - 125cc ), engine's to the square / Rectangular bottom tube.

I'll be posting a few how to pictures showing you where I cut my frames, and other pictures as I go through the build.

Here's what a stock / regular sized 20-inch StingRay Chopper frame with a 14.50-inch bottom tube looks like next to a XXL Chopper with bottom tube measurement of 30-inches . Notice the Xl Chopper Bicycles have a bottom tube measurement of 22.50-inches.






Here's what the Round Steel Tubing and Rectangular Steel Tubing I use looks like.



This what you'll be aiming for if you go for the 30-inch stretch for a XXL Chopper.



To be continued soon....I have to upload pictures of where I cut the frame, then I can post them.
Nice, thank you brother!

That's my current obsession.
 

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Tony01

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Nov 28, 2012
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Where's the pics for the frame building jig?
The link goes nowhere.
Maybe needs fixed
Old thread. Just figure out your own jig unless you want to pay $300 for a kit where you still have to buy the metal tubing. Got pics of mine in this thread.
 
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