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

[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

[wideopen231]

Well if you want to go real fast.I know Spider man LArry McBride uses whipple charger off truck setup.I know becuase due to his and dads name being the same they accidently shipped me 2 of his blowers.Man I hated seeing ups showup the next day.

As for injector idea I have done exactly like spud is talking about using carb.If its junk carb you can bore it out and make new butterfly. If doing so let me know I have little trick for making butterfly which is not really douns its little oblong. All you need is lathe and piece of round stock maybe 1.5 to 2". You need the end milled to about 10* and drilled and tapped (same pattern as shaft)to hold material for blade.When you turn blade on it you will have obong and the edge will be beveled like most factory units. Ive done all of my EFI harley units this way.

On the boring you can not get crazy normally due to casting of carbs. If go to billet liece you can make hiow ever big you want. I get into doing crap like this and if like contact me and if I can help let me know.

[hotrod316]

hi wideopen,

sorry just saw you posted.  Yes, I love the spiderman, that bike is very cool.  I would have told them that I never got a blower and made your harley RUN!!!

If you have experience boring out auto type carbs, have you ever messed with boring the sidedraft motorccylce carbs?  My factory service manual says that the 29mm carb is much beetter suited to the 1000 engine over the stock 26mm carbs.  I have found out that they are the same carb just the bore is different. Was thinking of opening up the carbs and seeing what I get in return, HAve a spare set sitting on the rack. 

And If spud sees this,  Have you ever ran some Nitro in Race Gas.  I was thinking why not just tip the can a bit and see what happens.   ... This way I dont have to fool around with increasing the fuel volume like i would if I converted to MeOH.  If I can get by with using the stock style carbs bored out and then playing with the nitro jetting I would be tickled pink.  I havent had any two wheel time yet this season so the simplest solution would be my friend at this point....

Thanks all
Matt