Stretching a Frame - But HOW MUCH do I stretch?

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Seems like every garage and tag sale in the region has an Orange County from Schwinn, but when I came upon a Huffy WEST COAST Choppers special, in red instead of chrome, complete with the chain guard and dummy tank, I had to have it. Even still has all the decals on the tank and guard, which I'm currently having replaced with airbrushing by an auto painter. Got it cleaned up, replaced the crank with another authentic, cleaned the chrome on the branded main gear and triple tree fork, and even upgraded the rear wheel to a Sturmey Archer 3-speed (preserving the coaster brake).

Then I remembered that I am 5'11" and this is a kiddy bike.

I've got the frame naked now, and thanks to obsessing over a thread on another forum, I've got the general shape of what I've got in store for me. That said, I'd like to make sure this is specced a bit more to my particular height and leg length.

So, other stretch cruiser/lowrider enthusiasts, I am 5'11", with a 32" inseam/leg length. Measuring from your bottom bracket, what are the lengths from there to the top of the seat/saddle, the rear dropouts, and the center of the handlebars? The lengths of your top, down, and bottom tubes could also help.

Thanks for any advice. :)
 
That is a very unconventional frame, so the usual rules of thumb do not apply.
-I have seen adults riding those Jesse James choppers, but it required a long seat post.
- I would stretch the seat stays and chain stays a few inches to accommodate a 24 in rear wheel and leave the rest of the frame as is. Just my 2 cents
 
Well, as you may guess the most important is the distance from the bottom bracket to the seat. I usually stretch the bike to almost perfectly match my size, but leaving still a bit of space for the adjustment on the seat post. Once you get this one you have a rideable bike. The base length would affect the handling, i have my longest bike about 2,2 meters and it is still okay, but my Dyno stretch that is about 2 meters long is even better. Remember you can also have a steering tube angle adjusted and some offset added on the fork, from my experience this helps a lot with control of the longer bikes.
 
I ride a lot of 20" bmx, I'm 5'11". 21" to 21.5" top tube is great.

If that frame is a laydown, stretch, Odd geometry, not sure what to recommend.

Thank you, assuming you don't have statistically really long or short legs, that works great for me.

I don't know if it would be called a laydown, but here's some photos of unstretched complete builds (stock).
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Legroom can be measured by the seat tube, from the BB to where the seat post attaches. If your normal riding height is on a 20" frame with the seat raised up 6 inches, (my inseam is 30 and my seat is raised 4 inches on a 20" frame) then measure the chopper frame to see where that would put your seat. Of course it's going to be laid back, but you'll be able to ride with our legs at the right angle. Then where your handlebars are is the next concern. Many people like to stretch forward, but I prefer to ride as comfortable as possible. I would get apes or half moon bars and adjust them to fit me.
This way you didn't change the geometry of the bike. But on your frame, it looks like there's only about 16" between the BB and top of the seat tube. Your seat post would have to be about 16" or more. A laid back post might put you behind the rear axle. A banana seat would also put you too far back. A stretch would be in order, unless dropout extensions were added. You could add up to 6" or so to the rear and not have to cut the frame.

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found this on face book. Looks killer! Now I want a JJ WCC!! Can’t do this with a occ stingray!
 
Looks cool....but un-rideable. Kneeing yourself in the chin every pedal rotation isn't a cool look.....
 
I think it’s a work In progress and it’s slammed for the photos. I’m a small dude, so I could make that work with a different seat set up.
 

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