Downhill Bike

Mungrul Downhill bike

At the first look at this bike most think it’s front is two high? They are right if you were mainly on the flat but! Remember it is a DOWNHILL bike put a 50 degree angle under its wheels you will notice the rider being level once the seat is designed correctly

I do not want to go into a lot of detail about this bike because it is my formula 1 idea a lot of thought and advice has gone into it even the image here is not detailed a lot due to my top secret position on it once i get to do my 6 foot drop off first then I won’t care who knows but you can follow the development of this bike here

Bike Drive

The power for the DH will of course be used for hill climbing and a substitute for peddling on the descent, once again allot of research has gone into the technology available the considerations has been of weight, torque, robustness, Two motor ideas want to try

Hub: the hub mounted idea is a 1500w hub built into the centre drive wheel, this would reduce the complexity of wiring and components needed to produce the drive, no chain, jack shaft, motor mounting with the frame would be needed giving space for bigger battery pack

Advantage: less complex wiring depending on aggressiveness of the ride it can be more robust for ruff trails and smaller drop offs easier to maintain by the rider allowing them to buy if wanted products from other suppliers

Disadvantage: more weight at the rear of the bike, the less robustness on more aggressive trails

Chain: this will be powered by an alien power converted RC motor to use hall sensors so a standard e bike controller can be used, depending on the power needed i.e. How much amperage will dictate what type of controller. The drive will be a center wheel driven by a sprocket and chain, this design may or may not need a jack shaft

Advantage: lighter in the rear of the bike adding most weight of the overall bike under the rider, freeing up space for center shock, interchangeable allowing the rider to change the power of the motor easily with out to much cost, high level of performance, bigger drop offs can be done with more aggressive trails due to the center mounting of critical drive components

Disadvantages: more complexity in wiring that can lead to Niggli issues during a session if not properly maintained, a good knowledge or the willingness to learn electronics to get the best from the bike, less standard options in the market meaning a knowledge or research needs to be done to get the desired performance.. advanced users with a prior knowledge of off road biking

Prototype in wood

So I’ve created the dies for the tube bender I just have to adapt the bender slightly to take the
51mm die.. also the tube notcher just needs a little work to be ready so I can fit the bearing
correctly for the hole saw to spin

First stages for the DH is a visual prototype, what dose this mean? Well simply put no bearings or
really functional engineering just 16 gauge tube building the frame wooden brackets instead of
aluminum everything as minimal as possible to give us an overall view of the bike that visually
we can see in real life

This will show us what changes need to be made after a few engineering people I know look at it
and can advice me on areas I have missed re-evaluate the size! To to big to small. To low to high?
In the way to far away all these things that can not be seen in CAD
This overview look at the bike is essential before allot of money is invested into areas that will
need to change later down the line

To date I have made two larger brackets and the swing arms out of wood the next step will be to
bend the tubes into place notch them and create the aluminum frame by building it on the jig I
have made