Balloon Donkey Bike

[deven_science]

I'm making a new Donkey bike. I'm going to try to make this one look like it was made in the 40s. Basically a balloon tire version of a velocino.

I started by cutting up a Schwinn World step through frame, and modifying a blade fork to fit this headtube and 12" wheel. The fork was actually a bit of work, as I cut and slotted it for the small wheel, then extend the steer tube, all because I wanted to use the headtube from the Schwinn.

 

[SwissGuy]

I'm making a new Donkey bike. I'm going to try to make this one look like it was made in the 40s. Basically a balloon tire version of a velocino.

I started by cutting up a Schwinn World step through frame, and modifying a blade fork to fit this headtube and 12" wheel. The fork was actually a bit of work, as I cut and slotted it for the small wheel, then extend the steer tube, all because I wanted to use the headtube from the Schwinn.
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Slap on a banana seat and you can enter the MBBO!
(2 of 3 criteria met) [emoji6][emoji3]

Gesendet von meinem K00E mit Tapatalk

 

[LukeTheJoker]

Very cool Donkey bike!

 

[deven_science]

Fabrication is done. Now, it's about finding the right bars and seat and so forth to make it a comfortable ride.

 

[LukeTheJoker]

Very cool!
Be hard to find a matching front fender I guess, but it would tie the wheels together nicely!

 

[The Renaissance Man]

Very cool! I've seen those but forgot that they were called Donkey bikes.

Is there any issue with the cranks clearing the front wheel when you turn?

 

[The Renaissance Man]

I went back and found this video that might answer my own question.

Looks like on this one that the cranks have a wide dogleg for clearance.

 

[deven_science]

Is there any issue with the cranks clearing the front wheel when you turn?

If I turned sharply enough, there would be an issue, but with the bars under my legs, there's not a lot of turn. It's not needed, either. Such a small wheel in front only requires a very slight turn.

 

[deven_science]

Disaster! I was test riding the bike, when I suddenly almost fell backwards.

I wasn't sure whether I could save it, or cut it up and start again, but I thought I'd give fixing it a chance. I heated it up, bent it back (with plenty of tubing damage to boot), then added in another set of stays.

If I keep it, I suspect that I'll have to age the thing up, add twine and baling wire, and make it look like it's got 70 years of barn crud on it to hide the repair. I don't know.

You can see I also added a front fender. I took a pink fender off of a girl's 12" bike, removed the paint, and made my own struts by taking a 26" set and hammering it flat, frilling a new axle hole, and putting it on there.
While the wheel cleared the chainring, the fender did not. So, seeing as how frustrated I was with this build at the time, and thinking that I was going to have to age it anyway, I just bashed the fender with a hammer to make it clear.

And a close up of the warped tubing.

 

[The Renaissance Man]

Just adds character. I can imagine some dad fixing the kids bike in the work shed after a bruising accident.

"There ya go son. Now be more careful next time."

 

[deven_science]

Added grips made from the fingers of a baseball mitt, something I learned from ratbike extraordinaire Ray Aubrey (cutnhack on this site). The patina of it matches the bike pretty well.

 

[The Renaissance Man]

Love the grips! I'll file that idea away for the future.

 

[deven_science]

She's pretty much done. I'll eventually get the second speed on this 2 speed Sturmey Archer hooked up, and I need one more axle nut for this rear axle. Turns out these 2 speed S/A hubs have a fractionally bigger axle than standard, and no nuts I have fit. Before it can be a daily rider, I need that nut.

 

[The Renaissance Man]

Good idea covering the injured tube with the coin.

This thing is very cool, how does it ride?

 

[deven_science]

Good idea covering the injured tube with the coin.

This thing is very cool, how does it ride?

Thanks, the coin was necessity. I tried to grind down the ripple and weld repair it flat, but I was making it worse, so on goes a clever doo-dad to hide the problem.

It rides nice, but I need to find one more of the right axle nut before I can ride it too far. The tire is rubbing a bit on one side as is.

 

[Grant]

How is it ridden?

 

[deven_science]

How is it ridden?

Here's a link to the video on my FB page.

 

[The Renaissance Man]

That settles it. I have to build one of these!

 

[GuitarlCarl]

That settles it. I have to build one of these!

I was thinking the same thing when I saw @irzouts Pontiac in BO9. Then I forgot about it until this build popped up. What's awesome here is the use of the vintage bike and keeping patina and badges etc. intact. I believe you have succeeded in creating a donkey that looks original late 50's and I too, like it a lot.

Carl.

 

[LukeTheJoker]

Absolutely love it! The bends and repairs just make it even better in my books!