# My Sister's Schwinn



## pntrbl (Jan 21, 2020)

I don't know if it's proper etiquette, but I'm puttin' a motor on this Schwinn. I live in pretty lumpy part of the world where a single speed Cruiser just isn't practical. For pedal work/exercise I use a cheap 29" Chinese bike from Wal-Mart. Judging by the tires, tubes, and brake pads on the POS I don't think the design life was more than 500 miles, but I've kept it going.  I just wore out my 1st set of Schwalbe Rob Roy's. I'm getting what I need out of it.

But I'm knocking on 68 trips around the sun and have no idea how long I'll be able to continue pedaling. But I also have this need to be on 2 wheels, and that's where the motorized Schwinn is gonna fit. If I can get up and walk to the bike I'll still be able to ride. Hopefully I'll still be buzzin' around town at 82 .....

So here's the general idea ... and what little boy didn't want to put a motor on his bicycle? It just took me 6 decades to learn how to do it.






49cc's of a Chinese 2-stroke tool motor designed for leaf blowers, chain saws, etc. Commonly found in pocket bikes. With modification it might be good for all of 3 hp. Uncontrolled wheelies won't be a problem ... 

Brakes could be tho! Depending on gearing it might go 35mph and a coaster brake wasn't designed for that. So I mounted up some hydraulic discs which is a lot easier to type than to do. Here's the front.





Needing a sprocket on the left side for the motor the rear caliper wound up on the right and below the rotor. I had no idea that was gonna happen when I started. The other thing going on in the back is when you put a vibrator(motor) on bicycle the frames have a tendency to crack at the chainstay. My solution to that was to chop the dropouts off and fabricate some nice thick horizontals.





That extra bit of slotting on the bottom is so the caliper mount (not made at that time) can follow the rotor which follows the axle which tensions the chain ...

The rear hub was an issue in that I needed a rotor, freewheel,and a sprocket all on the same hub. But I like a challenge and I own a lathe, so I made both hubs myself. Here's the rear.





That hub is my personal record for the most cuts ever inflicted on a single piece of metal.

Funny story on the spoke circle. 36 spokes. 360 degrees. 10 degrees a spoke. Right? NO you dummy! There's only 18 on each side. I made a few lovely pieces of scrap along the way.

I recently had it up to pedal status but it's apart now for paint.





So what I need to learn about now is how to get some bling on the bars. Restore a seat. Cranks etc. From what I've been reading this is the place to do that.

Thanx for looking and one more detail. It's got dual exhaust!


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## Freqman1 (Jan 22, 2020)

Cool build-great craftsmanship! Can't wait to see the finished product and a YouTube video would be pretty cool too. V/r Shawn


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## pntrbl (Jan 22, 2020)

Back on it's wheels and it ain't blue no more.









Rattle can job tho and I won't be doing that again. The line between orange peel and a run is so small it's just about non-existent. I managed to avoid the runs but there's a few "dry spots" in less than obvious places. Oh well. No one will ever see them but me. So why should I care?  I made that decision early on when I built the wheels but I'll be looking to do better in the future.

So what about these handlebars?





You guys do some amazing things with old chrome using OA baths? I haven't run across an explanation for what that is yet but if someone could further my education I'd be a happy camper. I'm also curious about the hole on the right side of the bars. My sister never touched a drill in her life. I know she didn't put it in there. Did it come from the factory that way? Is there some sort of cool accessory I should be looking for?

And what about the underside of the goose neck.





That's just about ugly. But it is the underside. Making it look better would probably be sufficient. I'm not wanting show quality. Just decent.


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## Rivnut (Jan 22, 2020)

I think you'd be surprised at what a nice OA bath would do for that chrome.  Do your thighs get a good sun tan from those dual exhausts?


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## Goldenrod (Jan 22, 2020)

No Clutch is a bit dangerous.  Can you kill it with the brakes?  Helmet and some love one watching with a cell phone is a must.  Do you have an idle control or is this flat out all the time.  You don't have a stand to practice on to change problems before launch like a Whizzer.  Don't confuse this motor with a King Chinese motor that is on the silver unit.  Have an exit plan please.  This looks like a broken arm or neck.


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## GTs58 (Jan 22, 2020)

That hole in the bars looks like it's all the way thru. If you're not going to ride with a stars and stripes stuck in the bars waving in the breeze, I'd replace them. New for around 20 bucks. Me myself and I would not ride a motorized bike with that set of bars. Maybe save them for a flag base on the 4th of July.


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## pntrbl (Jan 23, 2020)

Thanx for the responses. In order ..

Rivnut. I live in a desert where the sun shines 300 days a year. A good suntan is unavoidable. 

Goldenrod. Of course it's got a clutch. Centrifugal. You pull a rope to start it. And a throttle. As far as dangerous, are you kidding? 3hp on a bicycle? Thank You for your concern but I ride a Vintage 360 Yamaha that's got 35. My cheap Chinese pedal bike hit 32.8mph that day I rode it down Hwy 38 outa Big Bear. At the tender age of 62 I hit 99mph with a 175 on the lakebed at El Mirage. Had a 5 year bout with stockcar fever over a dirt track Pinto. Sportbiking over Angeles Crest Hwy and while I was real careful where I did it that bike was good for 135mph. I'm not worried about this bicycle. It'll be fine.

On the handlebars I wonder what member of the family put that hole in 'em. I'll replace.


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## hm. (Jan 23, 2020)

81-82 Schwinn Sidewinder bars or any type of mx handlebars would look fitting





Killer build with great fabrication skills. Interesting to see something different.. thanks for posting!


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## pntrbl (Feb 3, 2020)

I've mounted the motor in this bike 3 times. Once cuz I got it in there crooked. The 2nd time it was centered and straight at which point I realized the primary chain was hangin' way too far out the right side. A chain sawing on my leg didn't seem like a good idea. 3rd time being the charm I offset it over to the left and welded up a chain guard. It's safe now.





Both chains can be adjusted from the back axle because I mounted the jackshaft on a pivot. Here's the rear axle adjuster;





When I have the chain tension set I'll lock the pivot down. Here's the jackshaft from the other side;





That leaves me with no way to adjust the pedal chain but a simple spring tensioner solves that;





Next up is refitting the dual exhaust. I had it all done. The rear fender mount is an ideal place for it, but when I moved the motor over .....


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## 1motime (Feb 3, 2020)

A video of the maiden run is a good idea.  You can post if all systems are go!  Good luck.


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## Goldenrod (Feb 3, 2020)

pntrbl said:


> Thanx for the responses. In order ..
> 
> Rivnut. I live in a desert where the sun shines 300 days a year. A good suntan is unavoidable.
> 
> ...




I  am relaxed and supportive.  Great job.  I will be posting two like-yours bikes soon with cool additions you can copy.  We powder coat our rims over the orginal chrome.


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## pntrbl (Feb 4, 2020)

I've seen your posts in the Whizzer forum Goldenrod and ya just gotta luv those! My Dad had one as a teenager in the 40's. Are you guys actually working with OG Whizzer stuff?


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