The Ruscombe Gentleman’s Steam Bicycle

January 8, 2020 by Danie Conradie 16 Comments

Cycling for health and transportation might seem like a good idea, but it unfortunately has the nasty side effect of making you tired. To ease the suffering, many have turned to electric bicycles. But what if you want to really stand out from the crowd? Well then you should look to [Mark Drake] for inspiration, the creator of the beautifully engineered Ruscombe Gentleman’s Steam Bicycle.

[Mark] wanted to create a steam powered bicycle that’s actually usable, instead of just an awkward novelty. To achieve this he made extensive use of modern tech like spreadsheets to model the steam cycle, and CAD for the mechanical design. The engineering design that went into the project really shows in level of refinement of the end product, which is able to comfortably reach 15 mph. Watch the video after the break to see it in action and get all the details.

Petrol is used a fuel source, which is forced to the vaporising burner via air pressure. The fuel is heated by the burner itself to form a vapour before entering the combustion chamber and igniting. The steam generator is a hybrid design, using both mono tube steam generator coils and a small fire tube boiler. This produces superheated steam at over 300 °C, which [Mark] says is key to the bike’s performance. Mineral oil can’t handle the high temperature, so modern synthetic oil is used for lubrication. The steam generator is so well-built that [Mark] managed to get is certified to industrial standards. For safety, it features both a pressure release valve, and a system that automatically shuts of the fuel supply when the steam exceeds a certain pressure. 130 W of power is provided to the wheels by a single cylinder slide valve engine via modern toothed belt. This also drives the air pump to keep the fuel system pressurised, and an adjustable water pump to feed the boiler. Continue reading “The Ruscombe Gentleman’s Steam Bicycle” →

Vintage Bike Gets Briggs And Stratton Power

November 20, 2019 by Lewin Day 18 Comments

eBay made the process of motorizing a bicycle popular, with cheap engines from China combined with a handful of parts to lace everything together. If your tastes are a little more vintage however, [Oliver]’s build might be more your speed.

Starting with a real Briggs and Stratton liberated from an old rotary tiller, this engine has legitimate vintage credentials. Looking resplendent in brown, it’s paired with a bike in a similar shade from yesteryear. Drive from the engine is transferred by belt to a jackshaft, which then sends power through a chain to the rear wheel. The belt tensioner serves as a rudimentary clutch, allowing the engine to be disconnected from the drivetrain when disengaged.

The retro components, combined with an appropriate color scheme, make this a wonderful cruiser that oozes style. While it’s probably not suited for downtown commuting due to its lack of a real clutch and noise, it would make a great ride for taking in some country roads on a sunny day. We’ve seen similarly styled e-bikes, too. Video after the break.

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The DIY Open Crank Engine Moped

October 16, 2014 by Adam Fabio 50 Comments

Anyone can strap a two-stroke engine on a bicycle to create a moped. But [robinhooodvsyou] has created something infinitely more awesome. He’s built an inverted open crank engine on a 10 speed bicycle. (YouTube link) As the name implies, the engine has no crankcase. The crankshaft, camshaft, and just about everything not in the combustion chamber hangs out in the open where it can be seen and appreciated.

[robinhooodvsyou] started with an air-cooled Volkswagen cylinder. He filled the jug with a piston from a diesel car. Camshaft, flywheel, valves, and magneto are courtesy of an old Briggs and Stratton engine. The cylinder head, crankshaft, pushrods, and the engine frame itself are all homemade.

Being an open crank engine, lubrication is an issue. The crankshaft’s ball bearing is lubricated by some thick oil in a gravity fed cup. Even though the engine is a four-stroke,[robinhooodvsyou] adds some oil to the gas to keep the rings happy. The camshaft and connecting rod use Babbit bearings. While they don’t have an automatic oiling system, they do look pretty well lubricated in the video.

Starting the engine is a breeze. [robinhooodvsyou] created a lever which holds the exhaust valve open. This acts as a compression release. He also has a lever which lifts the entire engine and friction drive off the rear wheel. All one has to do is pedal up to cruising speed, engage the friction drive, then disengage the compression release.

We seriously love this hack. Sure, it’s not a practical vehicle, but it works – and from the looks of the video, it works rather well. The unmuffled pops of that low 4:1 compression engine reminds us of old stationary engines. The only thing we can think to add to [robinhooodvsyou’s] creation is a good set of brakes!

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Home Brew Motorized Bicycle Is A Super Grocery Getter

April 28, 2012 by Brian Benchoff 14 Comments

[Thor] sent in an awesome motorized bike build he found coming from the fruitful workshop of [Jim Gallant]. It’s an incredible piece of work built nearly entirely from scratch.

[Jim] welded the frame together on a home-built jig that keeps all the chrome-moly tubes in alignment before they’re pieced together. With the jig, the frame was kept extremely straight making a bike that turns very well and can be ridden no-handed.

All of [Jim]’s previous motorized bikes used small Honda engines, but after hearing Robin Subaru engines are more reliable he decided to give one a go. The motor is attached to the derailleur gears with a continuously variable transmission usually found in scooters. [Jim]’s earlier motorized bikes didn’t have indexed shifting and disc brakes like modern motorized bikes, but he decided to throw them in anyway. Everyone who rides his new super grocery getter comments on how smooth the ride is with these additions.

While [Jim] doesn’t have an official speed or MPG rating, he’s guessing this bike can carry three bags of groceries at 30 mph at 170 miles per gallon. A very efficient mode of transportation that is much safer than the other motorized bikes we’ve seen before.