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Spud, learn me please. FI on a race motorbike.

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hotrod316:
Spud and all,
 
This is Matt, Steve's son.  In addition to the nitro dragster that we run with my sister doing the wheel duty (thanks for the nitro help BTW) we are attacking some land speed records with my motorcycle. The bike is a Suzuki 1000 that currently is carb'd on gas.  Heres a hairbrain idea that has been floating around my head.

I want to convert the bike over to some type of fuel injection.  I have been looking into the MegaSquirt EFI conversion.  I have also been looking into the Hilborn injection system. Quite spendy from them but i think that is around for  the microsprints and might be able to get a nice used setup cheaper but i have not looked into this.  Anywho, the bike is total loss and it seems that most of the efi pumps draw huge amperage.  I think this may adversely affect my ignition as it also aftermarket electronic.  Is there a mechanical pump that I can adapt to bike use for use in EFI? Or is it possible to build my own mechanical injection system with some fixed orifice jets instead of electric injectors.

And to throw a munkey wrench into this plan.  At somepoint I may want to throw some fuel at the ole girl and see what happens.  So I need to design my system to be easily upgraded to handle at least MeOH but with the idea of yellow'ing up that clear alky...

So what are your thoughts and ideas. Ever had such a project...

Thanks
Matt
SMRacing

Spud Miller:

 Hi Matt,

 Doing either EFI or mechanical injection would be fairly straight forward. EFI will be spendy unless you do the megasquirt thing. I'd plan on using a couple of injectors per cylinder since any system you use will have the capability to do at least 8. That will allow you to use small, inexpensive injectors to get the required amount of methanol or nitro though them. You could indeed use a mechanical pump with a return style regulator. I'd suggest using a small electric pump to get the engine running if possible. Then the mechanical pump to take over the chores once running.

 A mechanical system would be inexpensive. You don't need to buy some ready-made thing...you just need a butterfly to control air. An old over-sized carb would work for that. Put a nozzle somewhere in the runners, a main pill and a metering valve on it and you're set. The hardest part is likely to be finding a way to drive a mechanical pump off the engine.

 Once you're tuned and running well with methanol, adding nitro to the fun will be a piece of cake!

 Spud

hotrod316:
spud,

thanks for the info. glad you gave me a place to start from, now my real work begins in doing more research and finding the necessary components for the conversion.

One more thing that I just realized I forgot to mention, my current ignition is considered a wasted spark type.  It has two coils 1&4 and 2&3. It fires one coil every 180 degrees, one of the cylinders in the coil pair being on TDC and the other on an exhaust stroke.  What problems would this create with the mechanical system with the constant flow through the injectors?  I would think bad things would happen with the nitro...

THanks
Matt

Spud Miller:

 Hi Matt,

 I don't think that's going to cause you any trouble at all. Heck, that extra spark might make some nice header flames :)

 Spud

hotrod316:
yea spud, after i posted i laid up that night and started thinking, forgot that theres a little thing called an intake valve and it closes and no fuel gets past. and then i thought heck we have unburned fuel cackling out the header pipes that makes a neat flame. and then you say the same.  scary thoughts huh...

now i am in the process of trying to build the motor to handle a little bit of fuel. then will work on the fuel system, aspect.  I think the suzuki base engine was used in a lot of funny bikes and top fuel bikes so there should be good references on how to adapt external pumps and the such to the bike. i will definately update here when i have something to show, thanks for the encouragement,

matt

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