Fuel Efficient Methanol 4 stroke engines (for quads)

[Swedishrigpig]

Dear all

A friend of mine is looking for Motorbike engines that can be ran on methanol. Not sure what the biggest difference is between Petrol and Methanol four stroke engines.

The guy is running a project in Africa and the people there can produce methanol whereas Petrol is horribly expensive. They need some small (500cc) engines so they can run their quads to the market and sell their crops etc.

Again, Fuel Efficiency is more important than Power and they need to be fairly easy to maintain.

Who makes purpose built Methanol engines that size? And where can I find them in the US?

Regards,

 

[TrackRat]

I don't know an engine source but they will consume about 1.8 times as much methanol as they would gas for the same power, so ethanol won't produce good fuel economy, per se. Engines run on 100% methanol have corrosion issues, require special engine oil, valve guides, valve seats, etc. for durability.

 

[TrackRat]

The above comment should say "methanol" won't produce good fuel economy and neither does ethanol, compared to gasoline.

 

[Swedishrigpig]

TrackRat

My mistake, It should read Ethanol (alcohol). Now, how can I correct my headline?

Thanks for your input. I see that the Specific Energy is much lower, so like you say, they will never be very fuel efficient.

http://en.wikipedia.org/wiki/Energy_density

Can any gasoline engine be started on Ethanol, or do you need to alter the ignintion and compression ratio etc?

 

[dgallup]

Ethanol has a lower vapor pressure than gasoline so starting on pure ethanol is a problem. For practical purposes 85% ethanol (E85) is the upper limit that you can get to start. You also have to richen up the fueling considerably.

The good news is the octane rating of E85 is very high (well over 100, from memory I think maybe 120?) so you can run a high compression ratio and get good power. The only problem with optimizing an engine for E85 is then you can not run it on gasoline so you have to have a reliable supply of E85.

 

[patprimmer]

You can start an engine on 100% ethanol or even methanol, but it is more difficult. A hot climate helps as does a very rich starting mixture or a squirt of petrol as starter fluid.

High compression also helps starting as does a very strong spark.

Ethanol is still corrosive, just not so much as methanol, so fuel system components must be compatible.

To be efficient you will want at least 12:1 compression and 14:1 or more is probably an advantage, depending on other parameters.


Regards
Pat
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[j2bprometheus]

What about using diesel fuel? There are small diesel motorcycles available:

Sommer Diesel 462
Sommer Motorradtechnik produces the Sommer Diesel 462. The engine is rated at 8 kW (11 PS). The bike reaches top speed of 65 miles per hour (105 km/h), and achieves 95 miles per US gallon (40 km/l).

 

[Swedishrigpig]

j2bprometheus

I think the idea is for them to use the Ethanol they produce themselves. It's part of the deal to make them less dependent on purchasing fuel and shipping it out to the countryside.

But thanks for the tip.