converting a 1985 zx 900 to EFI

[A2 turbo]

Didnt get the snow we were supposed to but was still dagum cold but Ive started the conversion anyway. the problems I ran into today 1) it was so cold I couldnt get the carbies of to begin with, but once I did it was d@mn near impossable to get the TB's on! I had to use the ol ladies hair drier to warm up the rubbers and take them off the head and put them on the TB's then put them on the head. with that done problem # 2) the 90 deg bend I used for the filter is too long it hits the engine #3) I put the tank on and the d@mned thing hits the plenum so I go to the shop and use the chop saw to cut 45 deg angles off the plenum and luckly I still have some aluminum to make a patch for both sides I didnt weld them in though just pop rivited them in place and sealed with silicone for now. tried to shorten the air filter tube but was still too long as seen in the pics will have to get that sorted before running, but hoping to get the wiring all hooked up and the ECU mounted tomorrow, and if time allows fix the filter and get it to start.

[A2 turbo]

[straitnate14]

I could never do somthing like this, just thinking about all the parts I would need would make me crazy. You got some serious skills

[A2 turbo]

Originally Posted by straitnate14

I could never do somthing like this, just thinking about all the parts I would need would make me crazy. You got some serious skills

thanks but it really isnt that dificult the microsquirt has a website and fourm with more tech support than you would ever need and the manual covers everything possable and cheaper than say msd or power commander

[A2 turbo]

Well I had good weather all day and hence worked on the bike all day (much at the displeasure of my wife) I got everything hooked up except the key on hot wire as I fogot to buy a connector. but I just wired it to a always hot on the fuse box for the attempts to get it started. at first I was thinking the fuel pump the I got on fleabay was buggered but I eventually pulled the injectors off the TB's and put them in test mode and guess what they sprayed fuel everywhere! so back on they go and with it in test mode I hit the starter button and roar she comes to life! but test mode only last for 400 squirts. running it in test mode I notice that in megatune Im not showing engine rpm so I pull the tank and find that my tach signal wire has pulled out of the connector! I fix it and retry but no go so Im going back to the manual to see if I missed something if not Ill be posting my problem on msefi forms and get bruce or matt to give me a response. once the tach signal is sorted tuning should go quick. I still have to tidy up some wires as I was trying to figure out the starting issue but no biggieheres some pics of todays work everything is on the bike but still have to tidy up the wiring

[A2 turbo]

At long last I hit the starter button and she roars to life! I still have a couple of things to button up before a ride but Ive loaded the ve table from the german high tech gpz and the bike idles and revvs up (I hit 10k before I knew it) the throttle is alot crisper than the carbs, their really snappy! I caint wait to go for a ride! I didnt get it started untill after dark so no vid of tonight but Ill do it tomorrow but its all down hill from here

[A2 turbo]

heres a quick vid of this morning
YouTube - GPz900 A2 EFI inital tunning

[A2 turbo]

been tunning all day go for a ride and come back make changes go for another, Im getting closer but still have some holes in the map. it would definatly be easyer on a dyno. I thought the germans map would have me pretty close to dead on but he had made his own ecu and used the same software so thats probably the diff either that or the stock petcok isnt letting enough fuel through. Ill know for sure once I get the O2 sensor hooked up (its not required but nice for tunning) Ill post another vid once I get it diled in maybe even one of a ride!

[A2 turbo]

here's another vid of a run to the store got some wind noise you can here when it stumbles and how smooth it is when it dont
YouTube - GPz900r EFI second ride still tunning

[huR/T]

hey A2, i saw how you determined the size of your airbox but how did you determine the size of the air filter?

[A2 turbo]

Originally Posted by huR/T

hey A2, i saw how you determined the size of your airbox but how did you determine the size of the air filter?

I took a gamble that a 2 inch inlet filter would work as thats the size of the turbo outlet so far so good

[A2 turbo]

I hered back from my friend Conny in sweden (UGLUK from the old 900 site) who has the GPz900R Turbo, heres what he had to say about my conversion (I thought I would share)

UglukGPZ900 has sent you a message:

Sv:I did it
Wow! That's just inspiring! I got to start looking into this myself. I've just quit my previous work for a new one that'll give me more free time, as well as the opportunity to surf the internet or read books all night..

I watched your vids, and it's so frustrating to hear just wind noise when you try to listen to the engine.. As far as I could tell, she's running real nice.

I certainly applaud your effort!

I fixed my bike two weeks ago, turned out to be the valve adjustment screw locknut come off, just like I suspected. The nut was laying on the head and the screw was halfway out of the tappet. Lucky I cut the engine just when I heard the noise.. Saved me a lot of work and some money..
Now she's on the road again.

Good to hear from you.
Cheers
Conny, Sweden

[A2 turbo]

I got the O2 sensor put in yesterday and tried to do some tuning. As I was on a datalogging run (with the laptop strapped to the tank) this cloud just dumps on me! i shut the top to the laptop and hauled arse to the house just in time. so I was thinking it il be a few more days till its tunned, right? well got to reading the megamanual some more and it turns out I had the O2 sensor wired wrong so I change the wires around watch some tv and go to bed. this morning I fire up the bike and let it warm up ( figure Ill see how well it runs now the O2 is right). Im ready for work I get on the bike and take off. Ill be dipped if it didnt run like a raped ape through chinatown! I hit the throttle and it was all I could do to hang on to the bars! Im still gonna hook back up to the laptop to check O2 readings and maybe turn up the afterstart enrichment (I had to hit the starter two times before it stayed running @ approx 30 deg F) but other than that ME THINKS IT'S DONE! I'll take another video so you guys can see and hear how well its running. anyone have any suggestions as how to reduce wind noise on the vids? I was thinking of putting some scotch tape over the microphone holes of the camera?

[A2 turbo]

the bike is running great! finally got a decent table going along with getting duty cycle and pulswith sorted Im ready for a dyno run if I can find one around here that dont want $89.00 a pull! to me thats just crazy! I guess Im just tight fisted like my scottish forefathers! Ill probbably not post to this thread anymore (I will post dyno slips once done) unless some decides to take the plunge and do the conversion and askes me questions here

[Risen]

I am new to this site but I come across your thread and liked your efi conversion on your 900, I to have a gpz 900 project myself that I have been working on and been going back and forth on carb or fuel injected, I have a EFI seystem off a gpz1100 how hard would it be to covert to the 900? what tune program are you using? Good job on your conversion

[A2 turbo]

Originally Posted by Risen

I am new to this site but I come across your thread and liked your efi conversion on your 900, I to have a gpz 900 project myself that I have been working on and been going back and forth on carb or fuel injected, I have a EFI seystem off a gpz1100 how hard would it be to covert to the 900? what tune program are you using? Good job on your conversion

Im not sure if you can use the ECU from the GPz 1100 but you can definatly make the throttle bodies and injectors work. Im using the microsquirt and megatune is the tunning software it is free on the megatune site and is avalable for pc/mac and palmpilot forms. the conversion is easy as long as you do your homework. read the megamanual and get busy! its a fun mod and very rewarding to do something most wouldnt even think of. next Im adding a flex fuel sensor to ETOH with the turbo which should go on this winter
by the way that looks like it will be very fun when its done

[Risen]

The throttle bodies and injectors are seprate so would I have to fab up a intake to mount them to the motor? I to have a new garret turbo that I would like to install as well so that Is why I am thinking about doing a EFI conversion on the motor. I will take a look at the megatune site for the tune software. I am wiring up the ignition and do you know if there needs to be a diode in the curcuit in order to get spark to the plugs. everything seems to be working fine but I just dont have spark to the plugs,I see that there is one in the curcuit when it was wired on the bike.