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Discussion Starter #1
I'm putting my '95 900SS CR back together after a bunch of refurb work. Part of that work included new CA-cycleworks coils, new plug leads and new main electrical wiring (battery to ground, battery to starter relay, starter relay to starter motor). I also did a bunch more stuff that shouldn't be relevant.

Battery is new and fully charged. Engine turns over quickly.

So it won't start which isn't a huge surprise. Started to debug that issue. Spark on both cylinders looks really weak to me (barely visible). Possible causes, trouble shooting procedure?

But more worrying - I am getting a strong spark from one of the case bolts that holds the starter to the case. See picture. Whenever I turn over the motor it will turn a few times and then a big spark and then repeat that process. I suspect maybe an internal short in the starter? But am kind of clueless on this one. I replaced the new relay to starter motor wire with the old one but that had no effect, still sparking.

988672
 

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I would say one of the brushes in the starter has packed up with grime or come loose from it's wire. It's possible to gently take the cap off the starter to look while still on the bike. That new wire to the starter you put on requires you to delicately remove the nut without turning the bolt at all - I'm guessing you let it turn. But it does turn the motor over, can feel the air pulsing out the exhaust from pistons moving?

The cap is a bitch to get it back on.
I found a source for the brushes only, if you need them.
The starter is supposed to be dry inside, no oil.

Having said all that, still not sure why you have a weak spark unless the igniters are shot or crossed? The starter draws more power than is needed to start. Maybe pull the headlight plug and try?

Where the alternator wire comes through the left side case - what condition is that in?

Hard to test the reg/rectifier if it won't run, but I wonder about it and it's connections?

That new ground wire has a clean mounting point? IE, no fresh thick paint?

Hate to mention it, but did you cross the coils/igniters so it is trying to fire at the wrong time? It just is not reasonable to suspect those new coils are bad,...
 

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i would refit the original coils and see if it runs with them. if it does, talk to chris at ca cycleworks.
 

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So let me confirm something - you hit the starter button and the engine turns over but won't start? You can hear the pistons moving or feel the air pressure coming out the exhaust? If so, the starter is working. It may be drawing too much power but that by itself won't keep the bike from starting.
 

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Discussion Starter #6
So let me confirm something - you hit the starter button and the engine turns over but won't start? You can hear the pistons moving or feel the air pressure coming out the exhaust? If so, the starter is working. It may be drawing too much power but that by itself won't keep the bike from starting.
Yes starter turns fine. Except for large, scary arc from starter mount bolt to case starter appears to be working fine. alternator wire condition appears good. I think ground from battery is good. But I will of course double check everything. All electrics appear to work fine though. Battery (new) does get drawn down really fast by start attempts.

I've got brand new FCRs on it so I am expecting a hard first/cold start but like I said the spark seems pretty weak to me. It is sparking on both cylinders but seems anemic.

For what its worth I can't seem to get the cap off the starter while it is on the bike. So I will probably bite the bullet and pull the starter and check it. Anyway to get off the starter without removing the left side case cover?
 

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The left side case must be removed to access a hidden bolt holding the starter on. It's not an overwhelming operation, be sure to record which bolt goes where as they are different lengths. If you have the paper gasket, set it down in a safe place and put each bolt on its hole as you remove it. Before placing the gasket on after replacing the starter - trace the outline on the cardboard so you have a reference for the bolts. Easy to mix up and if you try to drive a bolt in the wrong hole it will leak or crack the case. The new starter only goes in exactly one way, mark everything carefully

Ok, that electric arc must be dealt with, probably have a blown reg/rectifier now so start looking for one.

Would like another opinion on this, but I was thinking one of the starter bushes has walked off the job inside the starter and is short circuiting. Because you have been able to repeatedly run the starter it might be something else.It is easier to check - the wire attached to the bolt goes into a special grommet and non conducting washer that prevents grounding on the starter cap. If that is cracked or missing you basically have just wired your starter to ground,which will create the arc you are seeing, for a little while anyway - just until all the smoke is let out of your new wire, starter solenoid and starter and regulator and battery,...

So if it is not a grounded post, you have two options - starter replacement or bushing replacement. Bushings will wear out or break but the rest of the starter will work for decades usually.

If you think it is tough to get the starter cap off, just wait until you try to put it back on. Lining up those bolts while squeezing the bushes in place will cause you to run out of curse words. Try to arrange for a third hand and have a look at the Urban Dictionary before you start the job. You do have to disconnect the oil line hoses and one of the fittings on the engine case to provide clearance for the long bolt. Be absolutely certain you have marked its position relative to the rest of the starter housing, it goes in correctly only one way! Double mark it and take notes, pics. Note where the two tiny cut parallel lines are on the case and highlight them with some paint. If at all possible keep the rest of the starter case from moving while removing the cap, it will really save you some hassle preventing it from popping out of its seat.

Yeah, with this much hassle involved I would just get the bushing kit from Gotham and replace them rather than just pinching the bushing back into it's slot.

Reman starters are $80 to $685, so shop around. If you take it to a mechanic to have them replace the starter, be sure to get a quote on what he is going to charge you for that starter before he starts work. That exact starter has been used for 40 years on small farm tractors, big lawn mowers and snowmobiles as well as many brands of motorcycles so it really pays to research before buying. Remember that those '90's era SuperSports used many generic Japanese electrics which saved a lot of money in manufacturing over the old Italian made stuff.
 

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If required, I do have a spare used starter for a Ducati Street fighter 848. It fits many different Ducati models, look it up yourself. But PM me if you need one at a reasonable price. I no longer own a Ducati.


Sent from my iPad using Tapatalk
 

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Discussion Starter #9
Thanks all. Will dive back into this soon and report what I find. Thanks for the detailed description Rock, very helpful. I have removed many a case cover (and done bunch of bottom end rebuilds) so I am not concerned about the level of difficulty.
 

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Good luck, the more I think on it, the more I'm sure that starter post is not isolated properly producing the short circuit.

Let us know how the 39mm FCR's work out, I would love to put the 41mm on my second bike but the price is outrageous. The Keihin factory in Mexico is starting up soon but as far as I read last year the company will no longer produce these.
 

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A while back there were starters with a warranty for $100 on eBay.
 

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Discussion Starter #15
OK took the starter off and checked everything. No broken insulator on power terminal, no ground to the housing. Checked all internals. Brushes are worn but serviceable, no shorts, nothing. When assembled the power post DOES have continuity to the case as that is the path to ground for the commutator circuit but that path is through the commutator, I have verified there is no short.

Will be reassembling with a new cover gasket int he next couple of days and will see what the situation is.
 

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Never done it, but can you hook the starter directly to the battery to see if it spins? I would clamp it in a vice first if you decide to try it.
 

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Find two matching nuts so you can use the bolts to hold the case together. Clamp it in a bench vise, ground the vise to the negative post of a battery. Touch the starter post with the positive lead from the battery to see if it spins. You should not get zapped by touching the case while doing this or else there is a short.

I don't know what value you should get checking the windings of the starter armature itself, but that would be next.
 

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Discussion Starter #18
OK starter is back in and no short/spark. Starter turns fine and doesn't run down the battery in 30 seconds. So I think something was not making good contact and my cleanup and inspection got things back in working order. Spark, with stock coils, is able to jump an 8mm gap on both cylinders (using my spark tester tool) and that should be plenty strong enough. So I went back to the CA-cycleworks coils. No spark, wellt there was a spark or two on the vertical cylinder and then nothing. No spark from either coil except the brief moment on the vertical cylinder. OK so maybe I didn't get the plug leads on sufficiently so off come the coils, screw them down onto the leads good. Still no spark. Back on with the stock coils, good spark. CA-cycleworks coils test out fine as far as resistance in secondary and primary. But no spark from them. I can't believe I am just not getting the leads to make contact as it is a simple screw tap lead, hard to mess up especially on both of them, especially when I seem to be able to get connectivity just fine with the stock coils.

But I still can't get the damn thing to fire, not even once. I will check timing next but I am 98% sure the coils are hooked up right and I am not firing out of sequence. I know the FCRs are supposed to be hard to cold start but this is ridiculous. I know I have fuel (loosened bowl drains, yep gas, smell it in spark plug holes and in exhaust) but no idea if the mixture is even close, but it should be a basic setup for a 900 SS carby.

The journey continues.
 

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Interesting development.

Stay with the stock coils until you have it running. I assume you are using the original spark wires too?

Fuel, air, spark at the right time. That's all the variables and it seems like two of the three are insufficient.

Put a full overnight charge on the battery, it's not one of those Lithium ones is it?

So, pop the air filter out, give it a spritz of starting fluid, and hit the starter. Even on the coldest winter morning my bike will make some popping noises out of the exhaust like it almost is running.
 

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Rock is spot on --Fuel, Fire & Air thats all that is required to go vroom vroom---If the stock coils are firing as they should --shit can the aftermarket coils or send them back. I know some people just love some of these inferior aftermarket gizmo's --The CA cycle works coils you purchased dont work-this you already know.
Stop driving yourself batshit crazy & stop trying to out think the engineers at the factory---remember the KISS theory---Keep It Simple Stupid
 
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