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Would you guys like an instructable for this gas powered bicycle? Answered

I was wondering, who would like to see a detailed instructable with step by step instructions, lots of pictures, and parts lists for how to make this powerful motorized bicycle from scratch (without a kit)? The motor is a heavily modified 79cc horizontal stroke predator engine from harbor freight. The bike has a top sustainable speed of about 40mph. It also has enough torque to accelerate uphill, take off from a standing start with no pedal assist, leave Lance Armstrong in the dust, and do wheelies even with my 29" tires. Gearing can be adjusted for higher top speed at the expense of having less acceleration and hill climbing power. (Although in all honesty, I wouldn't gear it to go much more than about 45). Other features include an automatic clutch, the ability to get 170 miles per gallon, allowing you be cooler than all your friends, and costing a fraction of what you'd pay for a vespa. If you want me to make an instructable, comment below! Also tell me whether you might actually build one, or whether you just want to see how I did it.

26 Replies

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rasel88 (author)2016-09-10

This is awesome but i make a electric bycle chekout my instructable

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TheNecromancer13 (author)rasel882016-09-11

Where do I find this instructable. Also, I did end up making an instructable for my bike, here it is if you're interested: https://www.instructables.com/id/79cc-Motorized-Bicycle-From-Scratch/

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rasel88 (author)2016-09-10

check this my new creation electric bike

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goose57 (author)2016-03-22

It would not be comfortable riding this bike. The exhaust is much too close to your leg and thigh. The exhaust pipe would have to be placed elsewhere where it isn't intrusive.

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Toga_Dan (author)2015-12-01

is the engine still original width? that is the mainthing that has kept me from puttin one of those engines on a bike.

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user

What do you mean by original width?

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user

factory spec - side to side as mounted on the bike. do ya havta be bowlegged to ride?

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user

Oh, that. I attached some steel bars to the pedals to widen them. If it were still a normal bicycle, it would be annoying to have to pedal like that, but since the engine is perfectly capable of powering the bike by itself, it's not really an issue.

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user

gotcha. so basically it is a pedal assisted motorcycle.

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user
Downunder35m (author)2015-12-01

I still like the idea and did some research on the official stuff :(
Down here a bicycle with any kind of motor is classified as a "power assisted bicycle".
Sad part is that everything with two wheels and a combustion engine is classified as a motorbike - and needs to meet certain standards so it can be registered!! for road use.
So to have a small petrol engine on your bicycle means you need a motorbike license to start with.
Then the bicycle in question must be "suited for the used with a combustion engine" - and the manufacturer needs to specify what type of engine, max speed and much more.
Good luck finding a push bike that meets these criteria :(
But to make things worse: Back in the old days there was a moped - 50cc³ engine, max speed of 50km/h.
For some reason they totally abandoned the concept and corresponding part of the legislations.
This would have been the place where these motorrised bicycles should be...

Just though it post this as a heads up for interested people so they check their local rules and laws before getting fined.

As a sidenote: If you would find a suitable bicycle to be used with a combustion engine then you need to add lights, indicators and all that - plus wear a motorbike helmet, a bicycle helmet is illegal on a motorbike LOL

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user

Where I live, my bike is technically not street legal (cutoff point in oregon is 34cc, mine is 79cc), however I have passed 100s of cop cars and none of them have cared because for stuff like this, if I'm not being a jackass, they're not going to waste their time on me. Some of the cops even think it's cool.

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user

I would assume from your username and your "down here" reference that you're in Australia. If so, I would be cautious about building one unless you live in the middle of nowhere. From what I've heard, Australia is much better (read: worse) on enforcing their motorized bicycle laws.

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user

Well, around here quite a few of those 80cc bikes run around and pass the cops.
As you said, most can't be bothered and some still remember the days where we had mopeds.
But get a bad cop, run into a road check or cause any trouble with the bike and it is gone with a hefty fine.
With 40cc or less I can still consider the thing as an assisted bike, especially if you use a sprocket that provides more torque than top speed.
But even a modern mountain bike with disk brakes is no match for a 80cc engine IMHO.
I did a test ride on one last year when I considered buying one (price was too high though) and it was scary!
The bike took off like stink and I would say would have made it over the 100km/h mark with ease.
Problem was stopping the beast from speed.
Plus modern bikes don't really like the vibrations from the engine, aluminium welds have shown sign of early fatigue on motorised bikes.
Still, without bad cops in town I would still get one myself just can't afford to pay fines or lose my license over it :(

So I guess there are enough places left where people can use these things and enjoy them - when is the Ible coming you said? ;)

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pursang (author)2015-11-17

I would prefer a tank and engine at least half that size, with the exhaust running down under the frame, a much narrower engine placed lower ni the frame, the fuel tank could be a 2" full length tube running between the seat post and the steering neck, a smaller CC would also be quieter.

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TheNecromancer13 (author)pursang2015-12-01

If you want an engine much smaller than that, you gotta go 2 stroke, which means more breakdowns and a lot more noise.

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TheNecromancer13 (author)Kiteman2015-11-15

Normally, I wouldn't bother asking, but making an instructable for this would require me to build another bike, which would cost me quite a bit of money. However due to a friend of mine paying for the parts for me to build her one, I am now going to make an instructable!

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Kiteman (author)TheNecromancer132015-11-15

Excellent!

Make sure you enter it in the Epilogue contest, it would be in with a shot of a decent prize.

(In future, just take photos of every project you do, just in case it makes a decent instructabled.)

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user

one day instructable that seems quite a stretch

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user

Huh?

[Checks dates]

Oh...

Technology, then, or hold on to publish when another cool contest starts...

See: https://www.instructables.com/community/List-of-Up...

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TheNecromancer13 (author)Kiteman2015-11-15

I might make it to tech contest, depending on when the parts get here and how fast I work... would a motorized bicycle fit the tech theme though?

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user

somewhere on this site there is instruction on how to make a flux capacitor.........

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TheNecromancer13 (author)Kiteman2015-11-15

No way I'm going to be able to build another bike in just one day lol. Normally I do extensive documentation on any new project I start for future instructables, but this one wouldn't have worked, because it was not a new bike from scratch, but an engine swap with most of the other components and mods already in place, which were all done before I started making instructables.

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Toga_Dan (author)2015-11-14

i might build such a thing.

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Downunder35m (author)2015-11-13

Don't even ask....
Just do it and be amsed by how many people check it out.
Take nice pics and make it easy to follow and I would say you have really good chances to get it featured.

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seamster (author)2015-11-12

Yes, most definitely. The internet wants to see how you built this. Go for it!

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