12.5" OCC stretch

[el Diablo Guapo]

So this is a 12.5 " x 3.0 OCC toy bicycle

i am stretching it out large enough that i, a six foot tall man, can ride it, then i am putting a motor on it.

I found this tiny occ bicycle on Craig's list and knew it would be my next pedal assisted project...

It has probably taken a year to get back to it, but I have been going into work a half hour early each day for a week or so, and hope to keep that up til I finish. we will see.



The back bone is stretched 27". It has a 16" uptube stretch and I replaced the bottom tube with a 2 x 1" rectangle tube ~25.25" long (btw, thanks to Crazy Horse for the great thread on stretching the 20" bikes, i found it most useful.)

i have included a tape measure in many shots, and tried to capture some close ups of the fabrication

I did my planning with a graphics program, referencing the tape measure in my imported picture. I feel my planning cut down my fab time.

 

[el Diablo Guapo]

here i have disassembled the bike, cut the frame and begun mpounting this up
i apparently forgot to take pictures of my slugging process

it is simply, take some same/similar size tube, cut a three inch section. clamp the three inch piece in a vise endwise, with a crown above the jaws. use a cutoff disk on a grinder to cut a .5'" strip out of the 3" tube. squeeze with channel lock piers and insert. I also drill 1/4" holes in my exterior tube to rosette weld the slug in place.

notice, i also similarly used the existing bottom tube to act as a slug in my new tube, which assisted in keepint the original "triangle" of the frame, which in this case was important to me.

with the frame tacked up, i mocked it up, sticking a piece of pvc in the fork to get a rough idea and measurement of what i will need to finish the front end.

more soon i hope

i also dismantled, cleaned and greased both wheels. i am contemplating my rear chainring. with a twelve inch tire and a 44 tooth sprocket, the thing might do wheelies from low torque, but have a LOW top speed. I have some 28 tooth front chainrings from other bikes, and maybe some other odds and ends. prolly just guess in the end, and drill something out...

 

[GoreWound]

so much stretch!
I love it!

 

[el Diablo Guapo]

forks were a cut both ends, exposed insert (.875 OD .15 wall DOM tube - Amazon! ) tube sizes on this toy bike are really odd...

i really love the crazy handle bar attachment, inserted into the fork tube, but i also eliminated a key which prevented axial handle bar adjust ment, but was likely safer, as the handle is now only clamped in place.

this bike is low! the bottom of the frame is about 5 or 6 inches from the ground, due to the 12.5" rear wheel (r=6.25). the bottom bracket is almost as low. even thought he cranks are only 3.5" long, my heel sort of drags as i pedal.


so the basic bike is done- on to the motorizationicising!

 

[el Diablo Guapo]

fabbed up some mounts- 1.5 " OD tube ~55 deree angle cut(s), two independant brackets, this will allow a some adjustment at install.

hopeful about chain line - i am using a cup lid to emulate my rear chainwheel. it is a similar diameter, i taped it in place

i won't really know until i get the wheel assebled and on there

 

[Semaj]

Sweet merciful emperors teeth! This thing is off the charts in both the cool and cute categories,
oh and by the way its getting a motor.....
OH MY GOODNESS! x_x

 

[el Diablo Guapo]

Why, thank you

i anticipate it being a fun ride too, what with my butt so close to the ground and all

 

[el Diablo Guapo]

tiny drive chainwheel sprocket Re: 12.5" OCC stretch

the wheel on this thing is so small, only about a foot in diameter! that means it only covers about a yard per revolution. (12 x 3.14 = 37.68)

in contrast, a 24 inch wheel travels about twice as far (24 x 3.14=75.36)

using the same drive chainwheel in both configurations the big wheel contributes to a higher top speed but with more pedaling needed off the line, the little wheel will go slower but might be a wheelie machine! which could be cool, but i would need a tougher front end

i found one of my kiddie bikes had a 28? tooth front chainring, which seems enough smaller to be worth trying. it will still only get me to about 2/3 (or less) of the example - so this may be the begining of some tests

on the other hand, this may be plenty fast enough on this particular project

anyway the exisitng pixie bike sprocket center hole was milled out on the multi tool we picked up last year, and i also used it to quickly lay out the bolt circle. note the puppies on the sprocket !


i also needed a standoff or spacer to allow the rear motor drive chainwheel to clear the tire (12.5" x 3.0) i started with a 1.4" HPDE spacer (4" OD 1.75" ID, .25" holes on 3" bc ) - that item in the picture that looks like a rag joint is actually my spacer

this is not enough clearance. i will create a 1/2" standoff of similar properties and install it this week - the pedal chainwheel is out 5/8" or more. the frame is actually quite roomy here.

adding the chainwheel must proceed further steps, as the chain wheel determines the engine's final placement, etc

i also used my centering tool, it really makes the rag joint installation easier.
http://motorbicycling.com/showthread.php?t=52259

 

[Crazy Horse]

So this is a 12.5 " x 3.0 OCC toy bicycle

i am stretching it out large enough that i, a six foot tall man, can ride it, then i am putting a motor on it.

The back bone is stretched 27". It has a 16" uptube stretch and I replaced the bottom tube with a 2 x 1" rectangle tube ~25.25" long (btw, thanks to Crazy Horse for the great thread on stretching the 20" bikes, i found it most useful.) Thanks for the credit / mentioning of the " How To 20-Inch Frame Stretching Thread!

i have included a tape measure in many shots, and tried to capture some close ups of the fabrication

I did my planning with a graphics program, referencing the tape measure in my imported picture. I feel my planning cut down my fab time.

Freaking BRILLIANT, thanks now I have to go and change my under pants was so slap happy laughing and enjoying this custom Stretch build that yes I peed my pants a lil bit.

Fantastic build El Guapo, thanks for sharing all the details of your custom build, ie tubing lengths diameter etc etc, love this build KUDOS BRO...

Peace Crazy Horse.
P.S. If you facebook post / share this over there with the Group " OCC Schwinn Stingray Motorized Chopper Bicycles " everyone there will be impressed, for one I know I am..BTW, here is the link to the How To or DIY... frame stretching thread: http://motorbicycling.com/showthread.php?t=45155

 

[el Diablo Guapo]

Thanks Crazy Horse!

i'm glad you are enjoying this tiny/enormous cho-ped! as far as i am concerened you actually helped build it, your tutorial was so influential. no lie.
http://motorbicycling.com/showthread.php?t=29302

as far as credit, when i build on the shoulders of others, it just seems right to share that too.

and while i am singling you out in particular, really, everyone on this forum has helped me a little! so thanks to you all!

BTW CH, you seem like a guy who has done "several" projects. What do you do with 'em all? i need some ideas, otherwise i foresee a chopper estate sale in my distant future...

CH's sprojects
http://motorbicycling.com/showthread.php?t=44757

 

[el Diablo Guapo]

engine on 12.5" OCC stretch

i actually am further than this but these are the last pictures i took

i actually rode the thing for for a bit today, but my coaster brake mod failed - ack! but not completely unexpected...

I was really enjoying riding this. it is really fun, what with miy butt less than a foot off the ground, and my heels dragging from the bottom bracket at six inches, with 3.5 inch cranks. I cannot wait to get this dialed in!


anyway i got the engine in. i made some mounts, with the intention of adjusting them laterally before drilling, but it turns out my offset (to the edge of the two inch strap) was was just right. so the mounts line up with the frame.

the painters tape on the engine is so i can set the engine down, and whatever without scratching it. that drives me crazy for some reason

anyway here's pix, still minus fuel line and exhaust.


i made a killer temporary exhaust header 1/2" emt is a perfect fit inside the stock pipe. so i used a conduit bender and bent up the header.

 

[el Diablo Guapo]

yours truly astride the 12.5" OCC stretch cho-ped

for scale, yeah sure.

BTW it's a misnomer.

 

[Semaj]

The bowler fits the ride 100%! although I wear a top hat myself. It really came out awesome!

 

[el Diablo Guapo]

thanks!

i just have to work out the coaster brake.
the thick standoff for the rear drive chainwheel requires a (very)deep brake arm or extension or something.

the something i created failed after a bunch of test runs, but before i could film this thing rolling.

i am considering machining an extension, say a 1.25" rod with a hole in the middle and rectangular recess in the bottom and matching rectangle on top. then stack the extension on the cone and the brakearm on the extension, finish assembly as normal

has anyone seen an item this item for sale?

 

[el Diablo Guapo]

Can I mention this is for sale?

I hope it is not a faux pas to mention this is bike is on the block.

see the classified ad here:
www.ksl.com/?nid=218&ad=41949647

I would consider working with someone from this forum as far as shipping etc.
whereas i prolly would not just for a random person...

el