Motorcycle Repair: two wheelers - motorbikes, motorcycles etc running on cng, compressed natural gas, design constraints

Question
dear bill

sub : two wheelers - motorbikes, motorcycles etc running on cng

this is regarding some queries from my side
regarding two wheelers - motorbikes, motorcycles etc running on
compressed natural gas (cng) fuel source.

web url : http://en.wikipedia.org/wiki/Compressed_natural_gas

1. will there be design constraints i.e space limitations
in terms of fitting the newly design engine for the two wheeler
taking cng as the input fuel source ?

2.are there any safety precautions and risk mitigations required for driving if
the two wheelers are manufactured and tested to run on cng ?

i.e for example while driving the two wheeler is there any chance of explosion etc.   

i feel the cost of cng is less and gives more mileage/average as compareD
to petrol/diesels which costs more (liters) and gives less average.

thanks & regards,
prashant s akerkar

Answer
Prashant, I worked for a company that did CNG conversions for cars and vans. Biggest issue is where to mount a large, 3,000 psi high-pressure tank to store the fuel source.

The system basically was a dual fuel installation, where you could switch it off when the tank went empty so you could continue on regular gasoline.

Yes, there is a chance of explosion anytime a high-pressure volatile fuel is stored and exposed to outside forces of vibration, heat and the associated fuel line connectors.

There is less BTU values in CNG than gasoline, thus less power output, which can be an issue on smaller displacement machinery.

It is a good idea with some serious drawbacks and/or engineering challenges in a 2 wheel application.

Bill Silver