You may have trouble finding a ECU configured to fire at the correct time from a car, being a 2-stroke and all, unless you run 2 injectors per cylinder. A car fires and injector every 180 crank revolution. It may work
I think maybe you would be better to use a ECU that picks up off an ignition pulse rather that crank angle sensor. You would have to use a fuel only computer as well, and let the faco NSR PGM run the spark.
If you want to go down this road, id be looking towards the jet ski aftermarket for bits, as all jet skis majority of skis are injected twin 2 strokes.
Its a interesting quest your embarking upon. But if drag racing teaches us anything, a carb engine will make the same peak power as an injected engine. Not as smooth from idle through to red line, nor as efficiant, but top end performance wont be real different. _________________ Winning isn't everything, but loosing isn't anything
i have seen on the net a lad who fitted Fuel injection on a rd350 but not sure if he made it work if he ever did.............. have a look round the net
I'd stay away from that project !!! Fuel injection is far more complicated than throwing some parts together with a butterfly valve.... You'd have to have a computer to get the injector timing right, a fuel pump to provide the proper pressure, and some tiny injectors to provide the proper spay at such a low volume of fuel....
How about some cleaned up carbs that are tuned right ??? They do make the same power(as stated by 80xar), though not as smoothly as a fuelie.... But it's what the bike was made to use.
I know I'd hate to trash 3-5 engines trying to get it right _________________ MC21
04 NSR50R
93 CBR F2
98 CBR F3 track bike
95 VFR750
89 FL400R Pilot
90 FZR 4/600
The RD350 with FI was using a Megasquirt computer to control the injection. I read through his stuff with quite some interest but he doesn't say if it was any good or not. I believe that the same guy now has the motor fitted to a Cagiva Mito.
This guy used the carbs of an R6, fitted the injectors and built the fuel rail. That was probably the easy bit.
If you have a week with nothing to do then read through the Megasquirt manual (it's online) and see how it's done.
Certainly not the case of throwing a couple of bits of pipe on and pouring the fuel in, but maybe not as complicated as evyone thinks....maybe.
Concerning carbs vs FI. The beauty of FI is it's intelligence. Once it's set up, and if you're measuring enough parameters you can pretty well tune it to any situation. My mate's got an Aprilia SXV450 and we've already had a bit of a play and it's quick and simple. Now got the Tuneboy for it, so can really get stuck in.
anyone know what happens if the reed block is raised by 5 inches then the carbs sitting on top, that way the injectored can sit under the reeds and fuel can not be blown out as easily, or is that to do with port timing form honda. Closest snow field is around 1/3 of our Country north South away. going down saturday morning to grab some rectangle Tubing and try and find some light plate, have ten cutting discs, 6 injectors, 20 electrodes, the old tungsten carbide die set, Fuel pump(5ltr v Hope the drill bits hold up. _________________ HRC Is Getting Expensive
There is noway in hell a 6cyl ECU will work. 4 cyl maybe, but either way, it will need to be programable,which no std ECU are (besides WRX, EVO and LS1 V
Not sure about the whole reed valve placement thing tho. Id be trying to replicate a jetski design, as they work very well. but i'm sure they are rotory valve induction however, not reed.
Before you spend too much time on it, why not commuicate with some aftermarket ECU manufactures. Lucky AUST has he best support for this market. Microtech, Autronic, Haltech, Wolf, Motec ect.
What you are trying to achieve is definatly possibile, but unless you are a expert in EFI, have a dyno, and know the software inside and out, i dont think you'll reach your goal _________________ Winning isn't everything, but loosing isn't anything
But that's no reason not to try! _________________ MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball
What you need is a fuel only computer. Crank angle sensor and a TPS.
Keep the std reed block, in the same location. Use a machined alloy throttle body blank (i think a webber side draft would do) with 4 tiny injectors.
You would tune it off the tps and rpm inputs. Thats all you need really. You could incorperate a MAP sensor as well (NOT a AFM), but this makes tuning more diffcult, as you get a 3d map, not a 2d map
Basically, you'll have something like 10 mapping points at 250rpm intervals up to 15000 rpm. So 10 different throtle positions, that can be altered every 250 rpm.
You would just have to play with injector pulse timing and duration.
I would keep the std NSR spark control. _________________ Winning isn't everything, but loosing isn't anything
I'm go computer expert or electronic geek, but one thing I have learned is that if you want to do something then you have to give it a try.
Electronics has always baffled me, basically because I know nothing about it, but then when I decided to give it a go I found that it wasn't to difficult, as long as you take the time to read up spec sheets, instructions and so on.
FI is pretty much the same. If you can tell the difference bewteen rich and lean, and know how an engine works and it's requirements then there will be a way of compensating for it.
Start simple, like rpm and TP only, with an option for cold engine enrichment and this should get you going. Then add extra parameters as you get more familiar with how it works.
The guy that did this actually did get it running well it was just a matter of trial and error getting the right mapping but it is possible.
also here is a really interesting artical about the two stroke comeback which actual mentions that orbital the people behind direct injection used this system on an nsr125 to great affect. all these links show that fuel inejction and direct fuel injection are both possible.
http://www.eindiancompanies.com/pdf/comeback.pdf (two stroke comeback)
i know everyone thinks the two stroke motorcycle is dead but the technology is there to clean them up and i belive sooner or later someone is going to exploit the gap in the market with hopefully one hell of a machine.
hope this is of interest juan..
ps matt i reckon you should look into doing a fuel injection kit.
Last edited by juanv6 on Sat Nov 03, 2007 9:37 pm; edited 1 time in total
I remember reading about someone fitting F.I. to an RD500 somewhere?
Think he was Dutch or somewhere up that way.
Got it working quite well, if I remember right.
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Hope the drill bits hold up. 
