Hey Guys,

I am building a bike with a 2001 M2 buell motor.

I went for a start the other day and the motor fires but then dies.

I am running fuel straight into the carb via a hose and cut off coke bottle, so there is no problem with fuel delivery to the carb.

I have checked and adjusted the float level, stripped and cleaned the carb, replaced the float needle, checked the timing, checked the coil, plugs, replaced the leads, checked and rechecked all the wiring and earth points, checked the intake manifold for leaks and checked for bent valves.

Cant seem to find the problem,

I have been told on another site that it could be the ECM not providing spark to run after the initial fire.

If it is stuffed and i need to get a new one would i be better to re-wire and use a aftermarket nosecone ignition. They seem to be cheaper (for me in australia anyway) and offer more features that may come in useful later on when i do engine mods.

Has anyone here had a similar problem or could help out with any knowledge or ideas.

Your help would be much appreciated.

Rossie

Are you using the stock Buell harness? Have you bypassed the sidestand safety switch?

well it would probably help if you had a wiring diagram for the parts that you are using, there may be safety interlock that may need to be bypassed

I am not using a stock harness, done all the wiring myself.

I am using all stock 2001 M2 buell parts for the ignition and running of the engine.

I have a M2 wiring diagram in the workshop manual and used it to an extent to make up my wiring diagram.

I am not using the sidestand switch , clutch switch or neutral switch and have bypassed them in my wiring.

Any thoughts would be great.

Rossie

Hi.

Ok, the first thing we need to figure out is if it is loosing spark and fuel.

Use a spark tester(An in-line one) and watch to see if you loose the spark before of after is stops running.
If you loosing the spark as soon as you release the starter switch, check the power supply to the igniter/computer, you may not have power to it in the run position.
Also check to make sure your run switch is good.
If all tests good, then the Igniter/computer maybe bad.

Hey jeffytune,

I bought a spark tester on ebay today,
hopefully it turns up soon.

Thanks for the help
rossie

When you say "fires and dies", are you saying it fires only once or does it run momentarily, two, three, four separated ignitions; or do you mean one bang and no more? One bang and no more makes me think you may have set the timing on TDC of exhaust stroke. Initial timing should be + or - 5 degrees BTDC to start and advancing to 10-15 degrees at idle. If your piston is 180 out definately won't run, or if your timing pickup is way out won't run either.
Follow me? If you're getting spark on start, you're probably getting spark after start.

No, still no spark after initial fire (bang).

Spark is there, good and strong while cranking, as soon as it fires once, no spark,

You can keep finger on the starter and spark does not ruturn after the first fire, while cranking.

Spark comes back once you stop cranking and then start again.

Ecm must be screwed..........

I hope so anyway, just bought a SE nosecone ignition.

Any advice or comments always needed,
thanks to all who have replied so far.

Rossie

There's an interlock system with the clutch lever, the kickstand, and the neutral switch, to keep a person from taking off with the kickstand down. The kickstand switch is notoriously troublesome.

I don't have the schematic in front of me, but I *believe* they interrupt power to the module when the clutch is out, it's in gear, and the kickstand is down (as opposed to interrupting the secondary signal). If you have a voltmeter or test light handy, it's worth a look to see if the white wire going to the module is hot or not. Also check the white wire at the coil, it needs to be hot.

The other possibility is the plugs themselves. I've seen fouled plugs act exactly like what you describe. Got a sandblaster?

Hi,
I dont have a neutral, clutch or stand switch, so I dont need to worry about that, they are all interlocks for the starter circuit.

The power to my coil and ECM are all fine and my plugs are correct gap, colour, and are sparking realy well when pulled out and checked.

I dont have any connectors that could be loose or anything like that and all my earths are good and have been checked.

Everything points to the ECM, unless i am missing something real stupid.

heres a pic of my wiring, the loose wire are just taillight, indicator and brake switch.

Thanks
rossie

They're not just starter interlocks, they're running interlocks. If you have the motor running and you put the bike in gear, and let out the clutch with the stand down, the motor dies. But if all those things have been removed and bypassed, that shouldn't be the issue.

Best of luck sorting it out, hopefully you're right about the ignition module.