Ignition problems

[Doug]

Hi, I've got a 1994 900 Monster that refuses to start. I suspect the Kokusan ignition units are at fault. I've tested the pickups and get about 95 ohms resistance, when I first turn the ignition on I get a small spark at the plugs but there's no spark when I turn it over.

Does anyone know of a way to test the black boxes.

Thanks.

[slob]

600 rather than 900... any help?

http://avidflyer.wikia.com/wiki/582_Ducati_Ignition_Testing

[Doug]

Thanks for the reply, unfortunately it's a bit different from mine.

[fireman sam]

Ensure battery is fully charged check that the connectors under the coils are clean and fixed properly. Also check all connectors are clean .swap ignition boxes over .checking plugs are clean.It may be worth trying new plugs .check HT caps are screwed tight and have a good connection into cable.

[Nasher]

Doug

Good advise from Fireman Sam.
The M900 is very sensitive to battery condition, so charging the battery is the first thing to try.

It would appear unlikely the both ignition boxes would 'go down' at the same time, giving no spark at either plug, suggesting a fault that has taken them out, or a fault that is stopping them from working.

It's a very simple system, agricultural in fact, so with a wiring diagram it's worth starting at the pickups and working towards the coils with a meter to check continuity on every connector.

Another area to check is the kill switch on the handlebars, which can corrode internally.

Where are you?

Nasher.

[Flip]

With even the latest 900's knocking on a bit in years now, coupled with rather marginal gauge wiring in places to begin with I would also be looking at all the ground (earth) points.

If you are getting something at the plugs and they're sparking before gradually weakening then dying completely it could be a leakage dragging it down.

Have you got any 'funny' noises like buzzing or clicking etc. if you leave the ignition on?

Years ago I found on mine (and a couple of others since) that if I turned the motor off using the key I got a spark back at the main (yellow one under the seat) relay- probably as the coils discharged. This pitted the relay contacts really quickly and caused the bike to cut out intermittently (not nice while riding) until I found the problem and fitted a couple of 'bleed' resistors to take the charge away slowly- of course an easy fix and one I often still use is to turn the motor off using the kill switch.

As Sam and Nasher have both already said though- make it as easy as you can for yourself- ensure the battery is good and fully charged and go through ALL the connectors including the rubbish fuse holders (which are essentially just faston connectors held captive and open to the elements underneath) refit after cleaning using some Silicone grease and check with a multimeter as you go.

[Doug]

Thanks for the replies.

I'm in the north east near Newcastle, I haven't been on this forum for a while and for some reason I'm appearing as a guest even though I registered many moons ago.

I've had the bike from new, 23 years would you believe, doesn't time fly?

I suspect I fried the ignition boxes last weekend when I tried to jump start it from the car battery, a procedure I've done a few times over the years. I've checked all the connections and tested the various components for resistance values, ie pickups and coils but I can't find any values for the boxes themselves. When I earth the plugs against the engine I get a momentary spark when I first switch the ignition on, I'm also getting 12v to the boxes, but there's no spark when I turn the engine over on the starter motor. The Sherlock Holmes in me says that the boxes are goosed. They're expensive little so and so's and I want to rule them out before I spend my hard earned on replacements.

I'm also not able to swap with known good ones.

On a similar vein, anybody tried the Ignitech system?

[utopia]

A couple of times there you've mentioned getting a small spark at the plugs when turning on the ignition.
Just to be clear .. you are saying that happens without pressing the starter, aren't you ?
That seems odd to me.
Though electrics isn't really my best subject.

As an aside, its interesting what you say about switching off at the kill switch to prevent sparking at the main relay, Flip.
For some reason, dunno exactly why, I always switch off at the kill switch.
Maybe some half-remembered advice from the dim and distant.
Anyway, after 17yrs I'm still on the original relay and have never had any problems with it.
Seems to support your theory.

[Doug]

Yes that's right, with plugs out and resting against the engine, there is one small spark when switching on the ignition. It's not unusual, most of the bikes I've had do this when switching off or on, don't forget, that's the way HT coils work, a rapid change or collapse in the primary induces a voltage in the secondary, or something like that.

Like I say, not unexpected.

[slob]

I haven't been on this forum for a while and for some reason I'm appearing as a guest even though I registered many moons ago.

Database error a long time ago, email me :rob(at)ukmonster(dot)co(dot)uk and I'll try to fix it

I've had the bike from new, 23 years would you believe
Absolutely awesome!

I suspect I fried the ignition boxes last weekend when I tried to jump start it from the car battery
Quite possibly

[Darren69]

Unfortunately for you, I'd have to agree with Rob. Chances are you've fried both boxes by jump starting the bike.

[DaveR]

Doug
Unfortunately you probably did the damage with the jump start. One piece of advice I had when I brought my '94 900ss was... don't jumpstart it you'll fry the ignition boxes. i never have jumped it, plenty of other things, but not that.

[Doug]

Funny thing is I'd jumped it a few times previously with no ill effects. Maybe my luck just ran out this time, I've bought a pair off everyones favourite auction site so I'll bung them in when they arrive and see what happens.

[Tosh]

Just as a side note, how can jump starting fry the ignition ? Your still only using a 12v battery, just not the one on the bike ..

[Doug]

I'm sure it's got something to do with voltages spikes when connecting or disconnecting, some of the components can be quite sensitive to this. My mistake was using the car battery while it was still in the car with the engine running, I'm sure if I'd just used the battery on it's own I'd have been OK. Lesson learned.

[Dirty]

Funny thing is I'd jumped it a few times previously with no ill effects. Maybe my luck just ran out this time, I've bought a pair off everyones favourite auction site so I'll bung them in when they arrive and see what happens.

I've jumped mine off a car battery with no ill effects but it's ill advised. I wouldn't risk it again myself.

Just as a side note, how can jump starting fry the ignition ? Your still only using a 12v battery, just not the one on the bike ..

Electrickery is the devils hand and stuff of legend but I think it's to do with the amount of amps a car battery can/will deliver.

[Doug]

Just a quick update, received the replacement igniter boxes today and bunged them in. I only turned the engine over briefly with the plugs earthed against the cylinder head and we have sparks, yippee!

It'll be the weekend before I can box it all up again, but things are looking good.

Thanks for all the replies, thing is I still haven't found out if there's a way to test the boxes, seems to me that they either work or they don't.

[utopia]

For future reference ...
I've bump started my 750 monster in the past and was surprised how easy it was.
And the reg/rec was already blown and the connector block had fried itself (didn't know that at the time).
I have also jump started it from a car battery with no ill effects, but the battery wasn't in the car at the time.

[Dukedesmo]

Just as a side note, how can jump starting fry the ignition ? Your still only using a 12v battery, just not the one on the bike ..

It won't damage it by jump starting from another battery, as you rightly say a 12v battery is a 12v battery regardless of how big it is.

It might be possible to do some harm if you jump start it from a running vehicle that has a higher output or 'dodgy' charging system?