[TheSteve]

The relay board probably wouldnt be too necessary for this, and it would take up even more space. I added in a single relay of my own to control both the MS and fuel pump. It does make it much easier to do the wiring though since instead of soldering wires to the connector you can just use the screw terminals on the relay board

[Cheech]

Excellent. I got a little confused until I remembered that your newer posts are referencing putting on a MS system for a GSXR that you need the VR circuits for. I think I have everything straight now.

For the MS1 install, is something like this: http://www.diyautotune.com/catalog/m...unit-p-32.html necessary to do what I'm looking for?

[TheSteve]

Right, fueling is the easy part because the injections aren't really timed to specific events. Ignition on the other hand must be perfect within a single degree so its much harder to get a working control system set up for that. The only way to do both right now looks to be the GSXR trigger, but the Katana setup will work just fine for fuel-only (how I have mine now).

[Cheech]

I'm confused. So are you saying setting up the MS2 to control timing AND fueling won't work unless the signal generator is swapped for a GSXR (I'm assuming from the same model as the throttle body, 01-03?) So then timing should continue to be controlled mechanically, the TB/ECU will just handle fueling, and I don't have to rip my engine apart to swap signal generators?

Thanks immensely for the help on this.

[TheSteve]

Edit:

After drawing it out, its not going to work. The 2nd coil acting as the reset pulse but firing twice/cycle will just confuse the MS and cause it to lose sync. The only two options are:

1. Retrofit a GSXR signal generator to your katana (pictured below). Use an MS2 CPU running MS2-Extra firmware. Preferably on a 3.0 board, but either work and both will need modification. Youll need 2 VR inputs and 2 coil driver outputs. For the 3.0 this means either building a 2nd VR circuit on a daughterboard or using an HEI module, AND wiring in a second ignition driver (VB921) to an additional CPU output. For the 2.2 board, you need to build 2 VR circuits (or run 2 HEIs) and add 2 VB921 drivers. MS1 is NOT supported for this mode.

2. Wait for the Suzuki trigger wheel to be coded. This is a common wheel for nearly all 4 cyl carbed Suzukis, but still don't hold your breath. You may also consider making alot of noise on the msextra.com forums to see if someone will take interest and code it for you with you as a beta tester.


If the pic wont show, see here: http://www.msextra.com/ms2extra/MS2-...in_Trigger.htm
And I have no idea what years this came off of. It was either the oil cooled GSXRs or the 93-95 water cooled ones. Check the ronayers fiche, it may show it in more detail

[TheSteve]

The signal rotor is a steel disc bolted to the crank. The sensor for that is basically an unpowered electromagnet. When the steel points of the rotor pass by the magnet, it generates a small voltage spike. This spike is what triggers the igniter to fire the coils. This is known as a VR sensor.

So what we have at this point is a fixed timing signal. It will spike at XX degrees from top dead center of each cylinder no matter the RPM. So now the igniter box takes this AC waveform, converts it into a square wave DC signal, identifies which is cylinder 1 (from the irregular tooth), determines RPM, and sets the ignition advance based on that. On a post, it also factors in the throttle position sensor which is why the posts feel slow and weak if the TPS is unplugged.

If youre NOT controlling ignition, you can get an RPM signal from the grounds of the coils. If you ARE controlling ignition timing this wont work. Sort of a "chicken and egg" thing; the MS would have to see the coils firing to figure out when to fire the coils.

So if you want to control ignition you ideally would want to pick up the RPM signal straight off the VR sensor. Unfortunately the MS doesnt understand the long tooth of the trigger wheel, so at this point this too would become a fuel-only install on the katana. The old GSXRs I believe had 2 VR sensor pickups using a 1 tooth wheel. This setup works fine with MS controlling timing. If I was to try and control timing on the Kat I would probably disconnect the igniter from the coils, use the igniter's coil wires as the tach input with a twin trigger (to tell MS which is cyl 1), and use the ignition driver in the MS plus a 2nd driver to power the coils directly.

The problem with this is that the signal you'd pick up wouldn't be TDC, it would be the pre-advanced signal. So if the trigger wheel is at 5*BTDC, the igniters advance is 10*BTDC, and the MS is set to advance to 5* BTDC your total timing would be 20 degrees before top dead center. The only issue here is you'd never know your true timing since no one knows the stock igniters advance curve. Additionally, even with the MS set at zero degrees your timing retard amount would still be restricted to the timing dictated by the igniter. Shouldnt really be an issue unless youre running a VERY strange configuration. Even then you could perform the DIY ignition advance mod in reverse to retard the signal, then use MS to bring it back to wherever you need it.

Sorry for the long-winded post. With something like this there are tons and tons of different options if you hadnt noticed. I can try to MSPaint a few diagrams to help explain

[Cheech]

I thought ignition timing was controlled by the signal rotor which is mechanical, unless I'm missing something.

[TheSteve]

Do you ever plan on controlling ignition timing? If not then the MS2 is pretty much a waste. The MS2 supports all the extras like idle controllers, native ignition timing control, multitooth VR wheel decoding, etc. Its nothing you'll need on almost all motorcycles due to their inherent simplicity.

The 3.0 board is pretty nice for the extra hookups and native VR circuit as well as the proto area, etc. Again its not really needed here unless you need ign timing control. If I did it again id still buy the MS1 2.2 for this bike. For the GSXR I bought the MS1 3.0 because while I need VR decoding for the tach input I still don't need 3/4 of the functionality of the MS2.

Microsquirt looks very nice but for the price its not worth it to me. Maybe if I had a completely stripped down bike with no room under the seat.

[Cheech]

Well, it's on. I just ordered a set of TB's from fleabay, going to start amassing parts as budget allows. I'm oscillating between the Microsquirt, MS1 2.2, and MS2 3.0. My friend that is going to help me tune this thing once it's installed is saying a Microsquirt would be preferred since it was designed for motorcycles. I guess I don't really have a true basis for comparison since I don't know what I'm looking for in a EFI ECU to do what I want to do.

[TheSteve]

I think the only thing that'd be different for a post would be the TPS. You'd have to make sure the new and old tps function identically, or put the kat tps on the gsxr throttles. Then T off the signal wire and feed it to both the MS and igniter. Other than that it should be about the same except for possibly different fitment issues.

[Cheech]

TheSteve, excellent writeup and thank you for blazing the way on this. I saw you included the same essential parts list for the 98+'s, do you or anyone else know of any other gotcha's to do the swap on a post?

[Cheriff]

and the peasants rejoiced...

[TheSteve]

Alright, just spent about $300 on stuff. Actual prices were:

$187 shipped for an MS1 on a 3.0 PCB
$87 shipped for 01 gsxr600 throttles
$5 for the O2 bung
$6 for a frequency divider

Havent bought a fuel pump or the temp sensors yet but I've got my eyes on some cheap. I came up overbudget because I opted for the 3.0 board for the VR wheel. I also found a cheap way to use a 4 tooth crank wheel to control a 4 cyl motor: a frequency divider. It's a chip the size of a dime that mounts into the MS case, and with a few modded circuits itll cut the 8 pulses/cycle down to the correct 4 pulses/cycle. Havent found any documentation on its use in a MS environment but going off the spec sheets it'll be fine. I'll start a new thread in one of the subforums once the parts arrive.

[TheSteve]

Well with all the foreseeable parts tallied up its coming to $335. Less if I use an MS I have chilling here, and even less if I gut the katana (not doing that). The breakdown for that is:

$140 for a MS1 2.2 kit
$90 shipped for another set of 01-03 GSXR 600 throttles
$55 for an automotive fuel pump that I could likely adapt to the in tank pump bracket
$30 for intake and water temp sensors
$6 for a weldable O2 sensor bung to put in the exhaust
$15 for misc hoses, filters, wire

Issues:

CDI type ignition WILL fry the MS, so I may need the 3.0 board (VR sensor) for this which adds cost
Need to find a proper mount for the coolant sensor. Only place I can figure is in the radiator where the fan switch was, unless I want to drill and tap the thermostat housing.
Would like to run the stock airbox, so I have to seal the large holes in the box to the smaller throttles.

[BrianT]

Sounds like a project I'd like to try ... if I had the money, time, and skills to do it.