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Bandit 1200 Turbo EFI can't get out of it's own way

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4 hours ago, Blubber said:

Do these alternators need a "wake up" signal ? you might even call it a feed back wire.

Sounds like it it not putting out max voltage .. reason yet unknow

My understanding is that the Orange output acts as that due to it being connected to battery via the Red at the ign. sw.

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Based on the wiring diagrams I've looked at, Gixer1460 is correct. I've checked the wiring a couple times over, there's zero resistance between the alternator leads and the battery, and visibly it all looks fine. 

I've got a clamp type ammeter arriving later today thanks to Arttu's advice, going to check out my exact draws and alternator outputs when running, see if I've got a short causing massive draw on the system when running or something of the sort. 

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Good news today folks:

Fixed the second alternator! Popped the back open and one of the solder joints was loose. Re-soldered it and I'm putting out 13.5v at around 3,000RPM. Clamp ammeter showed that the alternator is putting out 11 amps at idle, and 25amps at just off idle. Power consumption is around 13 amps at idle, 14 at just off-idle. All is now well in my charging system, and I'll have a spare alternator lying around when the new one arrives.

However, the thing still can't get out of its own way, but at least it's not dropping cylinders anymore. My focus is now moving to the tune. Per an example of an oil-cooled MS tune I got from Arttu, changed from 2 squirts/cycle untimed to 1 squirt/cycle semi-sequential. It runs, but I had to increase the idle screw and change my idle VE from 22 to 60 to get a reasonable AFR. Gonna keep playing with the tune and report back. 

Thanks for all the charging system advice everyone, one piece of the puzzle is now solved. 

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1 hour ago, Fredrik_Steen said:

With a fresh battery, you should be above 14v when the engine is running. When I look back in logs, the voltage is around 14.3 - 14.4v. (Bandit generator)

I think the way I'm wired is messing with the MS voltage readings; log readings are consistently lower than a multimeter on the battery. I'm feeding the MS and pump out of the same fusebox, I'm going to take the fuel pump off and put it on it's own separate circuit and see what happens. Reason I bring this up is because my voltage readings with a multimeter are fine, but voltage while actually running and functioning I report from the datalogs. Regardless, battery is charging up right now, I'll report back with what I find when it's fully charged and running. 


Independent of this and on to tune stuff:

With 1 squirt per cycle and semi-sequential fueling, I'm only running on cylinders 2 and 4. Odd, as the bike fires 1-4 and 2-3 (unless I'm mistaken). I have cylinders 1-4 and 2-3 wired together for both fuel and spark, at least in theory. Wondering if I mixed up two of the spark plug leads when I did the LS coil conversion or fucked up some of the fuel injector wiring. Regardless, I feel like I'm making progress for the first time since I posted this thread. 

Edit: Am I an idiot? Should I have 1-3 and 2-4 wired together for the injectors? I think I'm 180 out on the fuel injection timing on the cylinders that aren't firing.

Edited by rider384
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Ok, took it for a quick ride, going to compile some information here:

  1. Charging system was bad, has been fixed
  2. When the Microsquirt is set on semi-sequential mode, only cylinders 2 and 4 fire. Doesn't matter if it's 1 squirt/simultaneous or 2/alternating, only cylinders 2 and 4 fire.
  3. After running on semi-sequential mode and turning the bike off for a couple seconds, it will actually run on all 4 with the fuel pump turned off, presumably from all the fuel vapor hanging around in the intake.
  4.  The bike fires on all cylinders when set to untimed batch injection, but it starts on two cylinders, runs on 4 after a couple seconds of idling, then goes back to running on 2 when the RPMs go up or load is placed on the bike. Presumably running 2 and 4 normally, and 1 and 3 running off fumes in the intake from ill-timed injection. 
  5. All 4 spark plugs are firing, 1 and 4 together, and 2 and 3 together

I speculate that something is off with the fuel injection timing/my wiring. I currently have cylinders 1-4 and 2-3 wired together for both fuel and spark, which I now speculate to be causing the fuel injection timing to be off by 180* on two of the cylinders. 

Should I have cylinders 1-3 and 2-4 wired together for the fuel injectors, and 1-4 and 2-3 for the spark? Do I have something backwards?

Edit: From what I've found online it really doesn't matter if injection timing is 180* off, so that idea is out the window. I'm going to swap the fuel injectors around and see if the running cylinders follow them. 

Edit2: Running cylinders followed the injectors! Guessing I didn't clean the fuel rail well enough after I extended it and it clogged 2 of the injectors. Going to order a set tonight with express shipping, can't wait to get them in and get a good run out of this thing.

Edited by rider384
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Seems that you are progressing.

13.5V and 25A from the alternator sounds ok. I guess your battery wasn't fully charged at that point so it was taking all the extra current from the alternator and keeping the voltage slightly low. Most likely once the battery is full you would see slightly higher voltage and lower current. However, 13.5V is already fine for the fuel injection and ignition. It's quite normal to see some variation between battery voltage measured by a multimeter and logged voltage. There can be some minor voltage drop between the battery and ECU. Also voltage measurement on the ECU isn't that accurate, around 0.5V errors are pretty normal. The Microsquirt has calibration values for battery voltage that you can adjust if you want to get the reading the same with a multimeter.

Good that you found the clogged injectors! Something like that would have been my next guess. As you mentioned injection timing or injector pairing shouldn't make any significant difference at this level. It should run on all cylinders no matter what phase the injectors are fired.

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Sourced some Fuel Injector Clinic 625cc injectors for an SRT-4 that slipped right in with some different o-rings and a small spacer in the fuel rail mount. Easy sub 1 hour installation, even with swapping the injector pigtails out. I also took the opportunity to lower the base fuel pressure from 3.5bar to 3bar, since I now have more than enough injector to run up to the limits of the stock engine. Bike idles beautifully on all 4 cylinders, albeit very rich, even with the change in injector size accounted for in the fuel constant. Hopefully I'm just down to tuning at this point. 

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