multifuel dirtbikes? Anyone created such a beast?

[mrming]

I'm curious, and looking for links and references. Has anyone converted your typical beat-up second hand dirtbike to multifuel?

By multifuel, I mean being able to run on gasoline, diseal, or even perhaps kerosene. It'd be a nice toy to have for offroading (my friends drive a mix of IH in diseal and gasoline) and potentially for if the roads are toast.

I'm looking forward to the responses!

[Squantos]

http://www.ericksonmotors.com/licmcc.htm

Link above is just for a concept multifuel engine. Not the entire bike per se...

Also there are mods to the KLR650 making it a diesel . Lots have been made for the USMC. Extreme range and durability......

[Exiledviking]

Yeah, the USMC KLR650 diesel is the first one
that comes to mind.
IIRC, something like 80mpg...!?

[Squantos]

Yeah I'm on the list for one when they start selling em to us civies.....:o)

I have a standard mogas version now that gets 75MPG and the diesel version if reported to get 150MPG with a troop and a basic and existance load doing 55MPH........pipe dream maybe but news was good even if the KLR650D only gets 100MPG.......

Stay Safe ......

[mrming]

I was hoping for something more along the lines of an engine conversion guide.. I know the basics, ie that diseal engines typically don't have plugs and operate at much higher compression ratios inorder to induce spontanious detonation..


But will it work well at lower compression and ignited by a plug ? Guess I shall be doing some research this evening..

[Grape Ape]

I believe that diesel is too thick to vaporize properly in a carbureted engine and isn’t volatile enough for a spark plug to ignite reliably.

If your bike is injected, and you can volitalize the diesel, you might have a chance. But diesel has less energy than gas (by volume) so expect to take hit performance wise.

If you don’t mind a little smoke and lower performance, you could probably use some diesel to stretch your gas.

[dustind]

Diesel has more BTUs(energy) per pound than gasoline, plus it is about a pound heavier per gallon. FYI The weight of gasoline is a better indication of it's energy content than it's volume.

You can mix gasoline with diesel. You may run into two problems if you run 100% diesel or a high diesel fraction. The first is that diesel has to be at a higher temperature before it will vaporize and thus ignite. This can make starting difficult especially if it is cold out. The second problem is the fuel may turn into a solid in cold weather. Adding gasoline can raise both the gel point and lower the flash point of diesel. I doubt you would want to ride a dirt bike at temps where fuel gelling is a major concern.

You should not need any engine modifications other than maybe an inline fuel heater to help get it started. I would try starting it without it to see if it is needed. Diesel fuel seems to be very tolerant to various air fuel ratios so I imagine you may not have to re jet your carburetor for it, but that is just a guess on my part. I am also not sure if a gasoline carburetor would work with diesel fuel. I could easily see the pilot or fuel/air screw gumming up easily.

You could add something like a Mega Squirt (http://www.msefi.com/index.php) DIY fuel injection system and retain the carburetor as a throttle body and backup fuel metering system if the electronics died out.

I plan on experimenting with some of this on my XR400 dirt bike that I use as my daily driver except during the winter. I already get over 50 mpg but I know I could do better with EFI. Plus multi fuel would be fun to have.

I know some people that have run their cars on diesel/Jet A and I think the only thing they did was add a lubricant fuel additive.

Be careful to avoid detonation. Most diesel engines run off of it, but it will destroy your gas engine if it is anything more than minor knocking. I doubt it will be a big concern unless you have a high compression ratio and lots of spark advance though. In cars detonation sounds like a can of marbles or tin foil being crumpled.

I would try starting with a low diesel high gas mix and keep working the ratios up from there to see if the engine stalls or not. Be careful to not let the engine overheat. A cylinder head temperature (CHT)gauge and exhaust gas temperature(EGT) gauge may be a good idea before running wide open on a new fuel.

There is plenty of information out on the internet. I have never fully researched this so do not take anything I said as gospel. I can easily tune gas engines, but I would have to look some stuff up before experimenting with new fuels.

[The_Antibubba]

I wish I could tell you where I saw it-I have it in a book around here somewhere :o -but i read about a guy who modified his bike's carb for alcohol use. Try looking at Teoma.


****

OOF! It's time to reorganize the library. OK, here's one reference:

How to Make Your Own Alcohol Fuels, Larry W. Carley, 1980, TAB Books, Inc.

He discusses carb adjustments, diesahol, and a water/alcohol injection system that increases diesel efficiency. Most of the Alcofuels books have similar stuff.

[Clean97GTI]

in theory, all you would have to do is bump the compression way up and eliminate the spark plug (or make it non-functional) to run a gas engine on diesel.
The problems this can create are numerous. First off, diesels are built quite a bit tougher than gassers. You are REALLY stressing the gas-spec parts out by running them in such conditions.
The camshaft(s) are not timed for a diesel either. You could find yourself blowing a good portion of the fuel out before it ever got hot enough to ignite...risking hydrolock.

You could reduce the compression, but then you risk a huge loss in power and possible engine damage. If that piston tries to compress an uncompressible mixture and fails...hydrolock can occur. Not a good thing.

[LAK]

I always thought a Willys Jeep or similar, powered by one of those little Kubota diesels used in their small tractors would be neat.
---------------------------------

http://ussliberty.org
http://ssunitedstates.org

[MillCreek]

This is what you need: USMC multi-fuel motorcycle (http://mocca.kaf.fi/teotwawki/dieselbike/specs.html). The USMC has continued to experiment beyond a diesel-powered motorcycle. This prototype runs on diesel, kerosene and jet fuel. Hayes Diversified Technology hopes to have a civilian version on the market in 2005.

[The Undertoad]

Hayes, thanks, I was trying to remember who was trying to build the civvy version. They've been trying for a few years, IIRC there was some bureaucratic holdup involving the EPA. I'd love a diesel KLR650, personally.

[pete f]

diesel kerosene and jet fuels are all light oils and reallistically the same thing with slight differences in volatility. home fuel oil is called often No 2 fuel oil. kerosene is a slightly cleaner level of diesel and also called No 1 fuel oil. some of the heavier grades need a higher heat level to flow. heavy bunker oil needs a lot of heat to flow well enough to atomise in a burner.

I used to work with a guy who had a Kawasaki mule 4x4 with a 3 cylinder diesel. we only fillled that thing up about once every three days. We figured about 60 to 70 mpg
http://www.trailridgepowersports.com/new_vehicle_detail.asp?veh=8329&pov=99208

[Ryder]

There are more comfortable two wheelers to go far on. If you have to stop to walk the circulation back into your butt every 40 miles what good is being able to have twice the milage? It will take twice as long to get there.

A 0-60 that takes over 10 seconds. What good is that? Have you guys never heard truck tires sliding up behind you at a high rate of speed with your feet are flat on the ground? I've relied on accelleration to keep myself alive way too much to consider getting something like this.

[Shovelhead]

Aslo check out http://www.m1030.com/