A 100MPG ride.

[Black_Moons]

A true 100MPG ride, Made in canada (More or less), For $715.

So far the cost has been:
Motor: $160
Bike: $25 at thrift store
Shift kit: $200
Carb: $50
Exhaust: $60
Misc parts/Material: $50
Paint: $30
Misc Bike upgrade parts: $140, Mainly spent on a heavy duty back wheel and 'Megarange' 7 speed sprocket, And new high quality chain, New brake pads and cables.

Time: Priceless. For everything else. There is cash.
Total Cost: $715

Savings: Lots. As I don't have to pay insurance. 50cc motor. Top speed 60kph~, till I tune it a little better and push it a little harder. Very good acceleration, And goes up even the steepest of hills without bogging down, (I live near a 30 degree hill or so and going up it is a joy done around 20kph, And the hill starts RIGHT after an intersection where the light is always red, So there's only about 20' to accelerate for a running start)

And overall, Its fun as hell to ride. I take side roads, mainly ride on the sidewalk as nobody actualy walks on it around here, Except in parking lots where I actualy go on the road. Sometimes I cruse at low speed. Other times accelerate at top speed and slam on the brakes just before the intersection. Everythings an obstical coarse. You just can't do that on the road. Not nearly as fun to ride on the road.



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Close up Picture of custom exhaust header I made, and bent with my torch after filling the sand with pipe. Also shown is the front mounting bracket I made, Extra large to distribute the force and lined with a precise fitted pipe to prevent crimping the tube.


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Photo of gas tank after being re-brazed, After it cracked. Turned the fillet braze from about 1/8" braze (known to crack) to about 1/2". Gas tank is held by a various lengths of 1/4" cylinder magnets (lengths made by connecting multiple 1/4" long magnets) to my arbitrary arm positioner. It made it very easy to reposition as needed to get the braze to flow properly in such a thick fillet without falling off.


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[Black_Moons]

Close up of fitting I made and silver brazed onto the tank to make a fuel gauge.

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Close up of exhaust, Before painting and some grinding with an mini belt sander.

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[Black_Moons]

This space reserved for future photos. :P

[The Artful Bodger]

Nice work!

[A.K. Boomer]

perspective

Wow what a gas hog, really --- isn't it amazing that my bro's 1990 honda CRX HF is rated @ 56 mpg (fuel economy.gov) and he's had tankfulls of over 60 mpg,
whats more is he's got a heater, a roof and windshield with wipers, can bring along a passenger and has a kick ass stereo,,, also has the option of going 110 mph if he wants -- all for under 400 bucks, im just saying --- where the hells all your fuel going

What could we achieve today (70-75mpg?) - over 20 years later with direct injection gas and variable valve timing? and why in the hell aren't we doing it?

We have the answers - were just not applying them.

if the arguments pollution control you really don't want to go there with the parts per million of whats coming out of that two stroke.

Hate to be a party pooper but Im just saying...

nice work though...

[MotorradMike]

Well done!

[Black_Moons]

Wow what a gas hog, really --- isn't it amazing that my bro's 1990 honda CRX HF is rated @ 56 mpg (fuel economy.gov) and he's had tankfulls of over 60 mpg,
whats more is he's got a heater, a roof and windshield with wipers, can bring along a passenger and has a kick ass stereo,,, also has the option of going 110 mph if he wants -- all for under 400 bucks, im just saying --- where the hells all your fuel going

if the arguments pollution control you really don't want to go there with the parts per million of whats coming out of that two stroke.
Hate to be a party pooper but Im just saying...
nice work though...

lol, Well, thats the problem when you limit to 50cc and not X hp. 2 stroke is a cheat on the CC limit. At least its only a 8000rpm motor, Some people cheat worse by getting 14,000rpm motors. Try making one of those quiet. The bike actualy IS reasonable quiet (Better then many cars that are driving around here), And I have plans to make it quieter.

As for where all the gas is going.. well, Out the exhaust most likey. An expansion exhaust does help however, As well as just well tuning it. Its not a very efficent design as its just not well supported by quanity of consumers. Its actualy very closely based to a 1940 german design. 2 strokes are not super efficent either.

Also, Wind resistance plays an important roll, as well as the mass that causes rolling friction and stop/go losses. Being as I only have 240lbs total mass, I still achive my 100mpg in heavy stop/go conditions. I could likey get much better fuel economy in a recumbent bike, Or by leaning forward a great deal. But I don't have a recumbent bike to mod, And don't like leaning forward much as it hurts my back. As such my bike is setup so I sit straight up.
As for the stereo, I have a MP3 player and earbuds, But I really perfer to keep my ears on whats going on around me.

But you are rather right, Its not designed to be efficent, Yet it still achives 100MPG. A better 4 stroke design can achive 150MPG, But at much lower HP for the same mass/size.

PS: I can bring along a passanger for 50MPG too. I have a second bike.

[Evan]

All it would take to get better mileage is a transmission. I need one for my trike that uses the same motor. We live at the top of a hill with a one kilometre long road from the bottom that hits up to a 14% grade. If I gear it down enough to make the hill it has crummy top speed. I need to figure out an automatic transmission for it or a workable torque convertor. I have been leaning toward a planetary transmission that will give a 2 to 1 change in ratio for hill climbing.

[MotorradMike]

All it would take to get better mileage is a transmission.

I think he still has the derailleur available for different ratios.

[airsmith282]

nice ride, iam auctualy doing a conversion for a guy with a gas engine on a chooper bicycle once his motor comes in, might do my own mountian bikes as well. that or ill find a chopper bicycle as well and do one up i kinda like the chopper look ..

[A.K. Boomer]

Your a good sport Black Moons, it is an out of wack comparison though,

The CRX engine is a 4 cylinder and each of those cylinders are 375cc, the entire engine displacement is 30 times greater and it has to push 1,800 pounds not including occupants.

[topct]

I think one of those Chinese Honda clone engines would work in a bicycle. The 50cc one. Heavier than what you are using, but they have a charging system built in and a transmission with a semi auto clutch. Not a whole lot more money than what your paying for that 2 stroke.

http://www.hooperimports.com/product...pf_id=50cc3A-t

You can beat that price by shopping around maybe. I see them on disposable pocket bikes really cheap also. Easy to quiet down to almost silent.

[hardtail]

Great job........I like your ball hitch clamp and your magnets for positioning.......nice job on the bung relocation. My only concern if you go off road and theres no spark arrester with that downward exhaust.........looks like thats the silver can though?

[DougC_582]

Just a note: the China 2-stroke engines have a few common problems built-in. If you want to play with one, read the guides at one of the gas-motor-bicycle forums (motorbicycling or motoredbikes) and you can sidestep a lot of problems. You can even make a few simple-but-nice improvements, if you have a mill and lathe to use.

The 2-strokes also pollute a LOT. There's 4-stroke engines though, China/generic and Honda or Robin/Subaru.

I think one of those Chinese Honda clone engines would work in a bicycle. The 50cc one. Heavier than what you are using, but they have a charging system built in and a transmission with a semi auto clutch. Not a whole lot more money than what your paying for that 2 stroke....

The Lifan engines work much better, but then you must use a moped/pocket bike/motorcycle rear hub. A bicycle hub won't hold up under that much power for long.

[Willy]

Nice ride Black Moons, looks good and hey, you still get your ass all over town at 100 mpg, not 20 mpg like in a mini-van.
I've done several of the engine kits and they are a blast, although none of the ones I did had the jackshaft/derailleur drive, nice addition.

Although not a sterling example of the latest technology in internal combustion engine design, they are easily made in a low tech environment and are basically a $70 dollar throw away engine, so don't expect stellar mpg and emission ratings. But still probably a lot "greener" than dragging your butt around town in a one ton dually in order to pick up a pack of cigs.

BM, I thought those engines were Chinese copy of an old Russian design?

Fortunately efficiency improves when you scale things up.
Using AK's bro's car as an example, at 60 mpg, I too have to say...what a gas hog his car is!
He's moving a ton down the road 60 miles and it takes a gallon of fuel to do it.
A new modern fuel efficient tractor/trailer combo can move that same ton down the road for well over 300 miles on a gallon of fuel...and that's payload! A freight train is much more efficient yet. Ships are again much more efficient.

So yeah, like comparing apples and oranges, still it's 100 mpg, no getting away from that.

Edited for spelling.