I've got this GSXR 750 injector rack I was staring @ yesterday.

So if we use the 2 center ones and re rack em they could fit the GS. But what else is needed to get it working.
So, lets start out with the misconception #1 - It needs more power - OK Maybe it could, however I'd venture to guess that a GS could make plenty of power for it. We only run 2 injectors, and 2 spark plugs. Top top that off the GS has a 11 amp battery, and the GSXR has a 12 amp - we have a ES10 - which is 11 amp, the GSXR has an es14, which is a 12. A GSXR also has an extra headlight and 4 inj and 4 coils. We'd need only 2 of those. A GSXR has a "rare earth" alternator, however I think that alternator is a lot smaller than the GS's.

So here goes the parts list. GSXR ignitor box, GSXR coils (I think impedance match is the main reason here), GSXR injectors, GSXR sensors - all of them including the water temp sensor which I'd venture to run @ the front center part on the motor. Any one think of anything else. Oh, what is used on the GSXR to advance the timing ... we gonna need a close replica of that guy.

I think its an easy task ... will it work and will it work right - whole other story ... not even going to go there, but is this all tha twill be needed to get to the point where we can attempt to answer that question

Cool.
Buddha.

might be easier to use megasquirt with the MAP and TPS in the gsx throttle bodies than fit the gsx ECU to the gs

I really hope you go through with this project man. Be a lab rat so the rest of us can learn from your mistakes. 

Why change the ignition system at all? Also, why not start out with parts from another parallel twin so that you don't have to worry about adapting or cutting down on the # of injectors and throttle bodies? The GSXR injector are going to be way undersized since they are designed to handle only 1/4th of 750 cc each. Whatever you use on a GS500 will have to big enough to support 250cc each (243cc i guess) be it the injectors or throttle bodies.

Quote from: skirecs on May 05, 2011, 07:20:24 AM
might be easier to use megasquirt with the MAP and TPS in the gsx throttle bodies than fit the gsx ECU to the gs

Easier maybe, cheaper, no.
Cool.
Buddha.

 
Another one of Buddha's "easy projects!"

You forgot cheap ...
I can assure you it will be both ... but wil lit work ... 
Cool.
Buddha.

My recollection is that the GSX-R uses a map sensor, a TPS (which you can mount to the throttle bodies) and an ambient air temperature/pressure sensor, and a crankshaft or camshaft position sensor.

Biggest issue is that the stock GSX-R ECU is unlikely to work as a simple plug-in install. At least with my 04, if you lose 2 injectors it goes into a limp home mode. On the plus side, there have been some efforts to hack the ECU, and I believe it is re-flashable.... So if someone in this community is really good at reverse engineering stuff, it might be do-able.

Wasn't there already a GS that was modded to FI?  Obviously its possible.  Someone would just need to copy on that design and improve upon it where they feel necessary.

Quote from: burning1 on May 05, 2011, 10:55:51 AM
My recollection is that the GSX-R uses a map sensor, a TPS (which you can mount to the throttle bodies) and an ambient air temperature/pressure sensor, and a crankshaft or camshaft position sensor.

Biggest issue is that the stock GSX-R ECU is unlikely to work as a simple plug-in install. At least with my 04, if you lose 2 injectors it goes into a limp home mode. On the plus side, there have been some efforts to hack the ECU, and I believe it is re-flashable.... So if someone in this community is really good at reverse engineering stuff, it might be do-able.

Reverse engineer is my middle name. In fact That also may be my college degree in.

So here is the Q then, so what if it is in limp home mode, we only got 2 cyls.

Crank posistion sensor - why cant we hang that where the ignition rotor is ?

I would get the whole electrical system from the bike, the entire thing ... and screw in each into the appropriate location on the GS.
I also thought it had a knock sensor, a exhaust temp sensor or I know it has an o2 sensor in the pipe cos they give you stuff to bypass it in some full exhaust systems, head temp sensor, and coolant temp sensor.
BTW if it uses a camshaft sensor - we are so screwed ... however a cam based timing even without it mapping into the carburetion is considered less reliable cos cam chain stretch affects that and its not a good way to do it. Crank is locked to the pistons, you can fire the mix wherever the cam/valves are even if they are a few degrees off. Do that with the piston off a few degrees and you can easily detonate ...

There is a benifit to FI only if you have all the sensors ... more sensors the better.
Cool.
Buddha.

Checked the Fiche. The 04 GSX-R uses a camshaft position sensor bolted to the valve cover. No O2 sensor or knock sensor to the best of my recollection, and there is no exhaust butterfly valve.

Just as an aide, I believe the new W800 is a FI Parallel twin. Maybe someone happened to find a box of "parts" on the side of the road after they randomly fell off the back of a truck  I'd think buying what was needed from Kawasaki would be prohibitive seeing as the W800 is a new bike.

FWIW

Michael

There is a guy that has done this on an RZ350 over on the RZ forum, here's a write up he did about it that he put up on his website:
http://www.smcomp.com/~smurph/RZ-EFI/index.html
I've also seen other posts about it and his progress on the forum, search under the keyword EFI:
http://www.rzrd500.com/phpBB2/index.php     Ed

Interesting project. I would recommend reading some basic fuel injection books before you start.  This will bring you up to speed (no pun intended) about mass air flow and speed-density FI systems.  You will see that the SD FI systems operate on volumetric efficiency look-up tables.  The better SD FI systems also have algorithms for transient conditions.  Needless to say this will have to be addressed, along with the timing maps, with the GSXR ECU.

As already suggested, you might want to see if the injector fuel flow rate, i.e. injector size, is properly sized for the GS engine.  I wouldn't base it of of cylinder displacement but engine power output.  The simple math is given in most basic FI books for determining injector sizing, assuming a BSFC of the engine.

Limp-home mode will resort to very conservative engine operating conditions only.  If you can reverse engineer the computer code, not an easy task even if you have a college degree, you can address this. 

FYI, batteries are rated in amp-hours, not amps.  This is an indication of the total energy storage.  The metric you want to quantify is the power output of the charging system, in watts.

Engineering has many judicious compromises.  Adding more sensors adds to the complexity and it it may only yield diminishing returns.  Something to consider in regards to "more is better."