MobiBike Team Rider: Alec G (at speed on our Isle of Man test course)

MobiBike Folding & Transportation
This bicycle is design for compact folding, there are two stages; 1) simple half-folding 2) wheel removal. Simple half-folding is very convenient, takes only 5 seconds but leaves the bike at its whole weight (22kg). Wheel removal & stem release helps break the package into 2 compact parts a) frame, bar & motor (17kg) b) wheels (5 kg), this makes lifting & stowage a lot easier. We offer the "ElBoso" Dahon bag as an option which allows for easy bike wrapping and a red nylon bag for the wheels.

Commuter Use - Car to Bike switch inside 1 minute

Departure: 1) Drive-in 2) Unfold bike 3)Ride-off

Arrival: 1) Ride-in 2) Fold bike 3) Drive-off

The Riding Experience

Extra weight of Motor

The MobiBike is primarily a bicycle, it rides as one even without running the motor. It feels like a bicycle carrying a load on a rear pannier, care has to be taken when manouvering/walking because the weight of the engine has a slight tendancy to pull the bike over. When riding you easily forget the motor, the riders weight above the saddle by far exceeds the leverage of the motor over the rear wheel.

Drive Belt

MobiBike uses a quality "Gates" toothed belt to transmit the motor power. It is far more efficient than "friction drive on tyre treads" (historical powered bicycle solutions). The belt is quiet, clean and very strong (kevlar re-inforced). There is a simple tensioning arm that keeps the belt safely loaded, it's set by hand and in extreme circumstances will "jump-out" preventing damage to motor, transmission or bike wheel. The belt does transfer a certain "drag" on to the drive train, it is noticable when the motor is not running, a similar drag to that of a strong dynamo. We encourage riders to only use the motor assist accessory when required, i.e. on tedious long journeys involving flats or inclines. We promote removing the drive belt and hanging it out of use for pure un-encumbered cycle use. The MobiBike has a belt hanging hook for times when you're not using the motor, it only takes a moment to release the belt tensioning lever, free the belt and hang it.

Belt hung on hanger when motor not in use.

Stopping - Braking system

The disc brakes are essential for the MobiBike, these "Avid" cable-disc brakes work very well indeed. The folding nature of the bike makes traditional hydraulic disc brakes impractical (folding high pressure fluid lines is not a good idea). Locking-up the rear wheel is relatively easy to do with the power of the brake system. The over-riding brake limitation is the ability of the tyres to stick to the tarmac. For urban riding, larger "balloon" tyres may be preferable because of their better stopping ability.

Drive Train - Clutch & Gear

MobiBike uses a single gear and a centrifugal clutch. Operation is very simple, the throttle trigger located on the right-hand handle bar is spring loaded to return to tickover at around 2,000 rpm. The centrifugal clutch bites at 4,000 rpm and slips according to load conditions. To accelerate you move your right index finger from the brake lever to the trhrottle lever and press to the desired level of aceleration. To decelerate you move your index finger from the throttle lever to the brake lever and press the front disc brakes. The procedure is very easy & natural, it's impossible to get caught in confusing situations where you are applying both full power and full braking. It is very safe. For left handed riders the throttle assemble can easily be fixed to the left hand side of the handle bars. We offer alternative gears that deliver a choice of higher torgue with lower top speed and lower torque but higher top speed. The standard gear is ideal for most conditions.

Speed, Power & Momentum

MobiBike is a bicycle with power assist, it is not a motorbike.

Take-off

Most people who try the cycle assume that they will never have to use the pedals, this is not true. The MobiBike is capable of making a standing start but it is not very attractive, essentially the motor labours at 4,000 rpm with the clutch slipping for 20 seconds whilst the motor tries to drag it's rider from zero to the natural clutch bite speed at around 15mph. A much better approach is to pedal the bike to 4mph, gradually apply the throttle whilst gently pedal assisting to 15mph. This pedal assist means that you acelerate to 15mph in less than 5 seconds, with a lot less noise and vastly less fuel. It is important to match every increase in road speed with correct pedal gearing, this helps deliver efficient leg power but more importantly bike control.

Gentle running

Many cyclists enjoy the feeling of freedom and relative quietness of bowling along the open road. It's still possible to get this feeling on the motor assisted MobiBike as long as you moderate your use of the motor. On a flat road 16mph is an ideal speed, the motor is barely delivering 1/3 of it's available power, the exhaust note has a non-intrusive gentle burble, the road speed is excellent for bike control, easy to brake to zero or for a change of direction. Often the wind turbulence noise heard by your ears is louder than the motor assist. The speed is very fuel efficient and least wasteful from a wind resistance perspective.

Up Hills

The MobiBike is excellent on mild inclines, up to 7%, you simply apply more throttle and the motor maintains your road speed for a little more engine noise and of course fuel consumption. Hills over 10% require pedalling assistance but do not assume that this is the same hard-work you are familiar with from cycling, you have a "magic hand helping you up that hill. There's a special mixture of inputs for most hills that deliver speedy progress without the sweat, the motor delivers maximum torque from low down in it's rev range, if you can keep the bike above 15mph by pedaling assist, thereby keeping the clutch from slipping and staying on maximum motor assist then you ascend the hill very quickly with the added bonus of a cooling air breeze to ventilate your body. This is where you pass every other push-bike cyclist whilst they labour in pedestrian pool of perspiration. This special mixture of inputs is using the physical momentum & the most efficient motor/human power inputs to attack the incline. If you drop down to walking pace then you fall off both motor peak and human peak inputs, you have to power out with your legs or become reconciled to a pushbike ascent. Hills over 15% inclines are hardwork on the MobiBike, when ascending 20% or above you are best to walk the bike and use the motor to pull the bikes weight alone, still a considerable help though. All of these limits will vary according to rider weight, rider wind resistance & final drive gear selection.

Down Hills

The most efficient descent is with the motor off and the drive belt hung-up away from the drive train, you will make similar progress a push bike although the extra weight of the motor will carry you a little further on to the flat. If you keep the drive belt engaged but motor off then the belt which causes drag similar to a dynamo and will become the limiting factor on a descent, perhaps limiting top speed back to 34 mph from a theoretical 40mph. If you run the engine then it's important to note whether the centrifugal clutch is engaged, if you've been ascending a hill at 17 mph then start to descend the clutch will still be be engaged and cause additional engine braking drag thereby limiting your top speed further, perhaps down to 27mph. If you apply full throttle down a hill then the top operating speed of the motor becomes the limiting factor , although not producing peak power the motor will run to 8,000rpm, circa 34mph (this is not good for the motor, will probably shorten it's life). The Motor assist kit is then a safety feature prevent cycle user from reaching dangerous high speeds. All of these limits will vary according to rider weight, rider wind resistance & final drive gear selection.

Acceleration, Top Speed & Handling

If you want to acelerate the motor works fine alone but legs and motor work better. At traffic junctions or roundabouts then a combination of inputs gives you a zippy solution. During aceleration it is very important to maintain the correct pedal gearing for your road speed, so that at any instant you can supplement the motor with leg power. Matching pedal gearing with road speed helps bike control, relying on the motor alone is not only lazy but it exposes you to more risks. You quickly become used to the extra weight of the motor, with correct tyre pressures the MobiBike is as easy to ride as any other bicycle. The front suspension and optional seat post shock absorber soak up most of the road imperfections giving you smooth and easy progress in most urban environments. The MobiBike on standard gearing of capable of approaching 28mph but running at maximum power output is not recommended, the motor manufacturers rate their engine at 80% for continuous output. There are other issues with these speeds, other road users do not expect cyclists to maintain near 30mph on the flat, it can cause mis-planned over-taking by other vehicle drivers, you have to stay aware of the situation, rear view mirrors are recommended. Wind resistance is also an issue at high speeds, casually dressed riders are likely "catch" a lot of wind over 20 mph, often this makes the bike control more difficult, especially so in blustery or side-wind conditions. If you are familiar with the thrill of racing down a steep hill on a push bike, you will remember how it focuses you on your planned course line, makes you look further ahead and pre-loads your index fingers on the brakes, running a MobiBike at full pelt puts you in this situation all the time, a helmet is obligatory.

Front & Optional Seat Post Suspension

Fuel & Range

The fuel tank is integral with the motor, it is slung underneath and has 650ml capacity. Range is affected by the the terrain, head wind, riding style, rider weight, tyre type & inflation. 25 miles per tank should be possible. We've used aluminium bottles as spare tanks to double the MobiBike Range. Bio-Ethanol is clear in colour than petrol/gasoline, it continuously evaporates under scrutiny, great care should be taken when handling because it is highly flammable. The tailpipe exhaust fumes do have an alcoholic smell! A single gallon fuel container can carry 150miles worth of fuel. We offer a petrol tank siphon-pump for owners or BiotEthanol running automobiles which means that they have no need to carry supplementary fuel cans (which can be illegal in some countries).