Engine stops suddenly, ignition issues?

[Niels Mouthaan]

Hi, first post here and happy to see the activity of this forum.

I have a 83' XS650SJ with a Boyer Bransden ignition that runs fine when warm. A few weeks ago my bike started acting strange as it stopped running while driving and in most cases after rolling out with the engine turned off it occasionally started running again. The issue started to get worse and at some point it was very hard to go somewhere as it was very unreliable. At its worst moment, when the engine stopped while driving, I had to wait a few minutes enabling me to start again and drive home slowly (low revs).

I was pretty sure the issue was caused somewhere in the ignition and I turned to be right here: after measuring everything with a volt/ohm meter I found that one of the spark plugs had a significant higher resistance compared to the other (200k vs. the normal 5k). I replaced the spark plug and the bike was running fine again.

However, since a few days I started having issues again. I am not sure if they are related but again I have the feeling something is wrong with my ignition. At random moments the engine just stops. It's like the ignition key is turned off. However, my front light still works (which is not the case when you turn the ignition key off). When the engine stops and I'm still rolling, I can turn the ignition key off and on again and it immediately starts. When the engine stops in front of a traffic light I actually need to start it manually (obviously, as the bike is not rolling anymore).

The issue happens when running idling or when riding. It also happens when cold or hot. The difference between the current issue and the issue I had a few weeks ago seem to be related yet different as currently the engine really stops completely while it used to run bad before it actually stopped.

Do you guys agree it's likely that the ignition is causing this? In that case would it be likely the coil or the ignition box? Could it also be bad timing? I am asking because I removed the stator plate to clean it a bit and might not perfectly put it back causing some timing issues. After this I noticed a slight change in idle RPM (going down). I ordered a timing light to help me determining the right timing. However, since the engine simply stops suddenly I'm wondering if it is the timing at all.

Any help is appreciated. Thanks guys!

 

[peanut]

Hi Niels
sorry that you post has not received a reply before now. I guess its all to do with time zone differences .

Its an intriguing problem that you have and difficult to diagnose due to it being seemingly random and intermittant.
However one thing in our favour is that you say the engine cuts out dead whether on idle or WOT .

This sounds to me like a simple wiring connection issue . I think what is happening is you have either a short somewhere or a poor connection either in a component like your ignition switch, fuse block, cutout switch etc or somewhere in the wiring and grounds associated with your ignition system.

I would use your electrical schematic to go through the ignition system wiring carefully especially the connectors and wiring in your headlamp bowl and under the tank to check for shorts or poor intermittant connections. it could be occuring when you turn the steering or hit a bump for example.

You could try pulling the wiring a bit whilst the engine is idling to see if you can find a wiring loom problem
Don't forget to check all the Boyer box connections .

 

[Niels Mouthaan]

Thanks, I will definitely start looking at this.

One additional thing that came to my mind is that when the engine cuts out when riding, I can easily restart it by simply switching the ignition switch to off and on. I have not tried this with my kill switch as that hopefully has the same outcome (as it is easier to use when riding). However, it seems like a "reset" makes it working again. It would be helpful to know what exactly I am resetting (the ignition box?) so I can start looking there first. If it's really a wiring issue I would be a bit surprised since this wire would cause something to happen that only can be recovered by "resetting" and does not restore itself. Unless a specific wire/connection would cause this, making it easier for me to locate the issue.

PS. I have had the issue when accelerating after a traffic light, while waiting for a traffic light and while driving 60km/h. Hence, no specific behavior such as steering, breaking or bumps seem to cause this.

What kind of sensors and switches are influencing the ignition when already running? I can think of the ignition switch and kill switch. Anything else?

 

[peanut]

possibly the safety relay . Relays can be very intermittant with poor grounds or high resistance contacts and connections .

On the later bikes the ignition wiring was fed through a number of safety steps Your year I believe had both a clutch switch and a sidestand switch for example

Check ignition switch ,clean switch contacts (added thanks to Angus)
I would check your ignition fuse 10A carefully with a multimeter to make sure there is not an intermittant connection by wiggling it around
next check the stop switch
Then check your sidestand relay

The feed for the ignition is fed from the battery through the fuse block (20A) to the ignition switch back to the fuse block (10A) and then through both the sidestand relay and fuse block before it reaches your coils.

If you cannot find a fault with any of that ,you could try bypass all of it and run a temporary 12v+ wire from the 10A ignition fuse to the coils R/W and see if that cures it

 

[madjap]

Would that late of a model (1983) have a neutral safety switch? A kickstand safety switch? I had a Ninja 1000 that had those symptoms and it was the stupid kickstand safety switch! Good luck! It sure SOUNDS like a simple connection issue.

 

[angus67]

How old are your plug caps?

 

[peanut]

all years with a starter motor had a neutral switch but that effected only the starter operation not ignition.
What do you mean by 'kickstand' ? do you mean the sidestand ? or main stand .

 

[Michaelo]

Hi Neil's, as peanut has pointed out, with grounding, poor contact in switch, relay, start with grounding wiring and start working your way through.....you will find it.

 

[Niels Mouthaan]

@angus67: one of my spark plugs was replaced a few weeks ago as the resistance was signifiant higher than the other one. This actually solved the issue I had back then.

I looked into the manual and the following is described about the sidestand relay:
The sidestand relay operates by shorting the TCI control current. When the sidestand is down, the sidestand relay is closed, and the TCI control current is grounded through the sidestand relay. Thus, the engine will not run with the sidestand down unless the transmission is in neutral.

Screen Shot 2016-09-07 At 3.36.14 PM

• Niels Mouthaan
• Sep 7, 2016

In other words, if the sidestand switch indicates the sidestand is out, the engine will stop unless the transmission is in neutral. Hence, it actually does operate the ignition when already started.

One thing I still don't get is why the problem fixes itself by turning off and on the ignition. If it was a sensor/wiring issue, switching the ignition key on and off would obviously not spontaneously fixes this.

Anyway, I will start looking at it. Thanks for the help!

 

[peanut]

what do you mean by 'turning off and on the ignition' ??
Are you saying that your ignition light goes out when the engine cuts out ?
If so then you should be looking at your ignition switch and associated wiring

 

[Niels Mouthaan]

I mean turning off and on my ignition key. Basically that "resets" the ignition immediately starting my engine again when in gear and my bike is still rolling. I know resets sounds silly but for some reason that gets the thing going again. Until I haven't turned off and on my ignition key, it won't start. Turning off and on my ignition key will also turn off my headlight as that keeps working when the engine cuts out (I believe as a result of the headlight safety relay that will cut out the headlight until the engine starts - probably the alternator is still producing power making the relay believe the bike is still running).

 

[peanut]

well your description strongly suggests that a relay is at fault as a relay is about the only componant I can think of that could re-energise on power on.
Sounds like some electrical fault like a dirty contact or intermittant short is causing a relay to de-energise and re-energise when powered up again.
I'd go straight to the sidestand relay and remove it clean the relay contacts and also the terminals in the elecrical connector on the loom. Also check the sidestand switch fitting and adjustment naturally .

 

[grizld1]

Years ago I had those exact symptoms in a D model with a Boyer Micro Power ignition (no sidestand relay, etc.) The engine would run fine for awhile, die suddenly, and restart at once if I flipped the kill switch quickly off and on. After metering out the pickup coils, ignition circuit, and coil and finding no defect, I was reduced to swapping out components. The culprit was a bad igniter box.

 

[angus67]

my 71 did it, it was cold solder in the ign switch.yours sounds different though. but still might want to look

 

[peanut]

my 71 did it, it was cold solder in the ign switch.yours sounds different though. but still might want to look

yes that a very likely culpret Angus, good shout. I just checked my initial reply and realise I forgot to add it to the check list .

The ignition switch contacts can get very oxidised. I recently stripped mine and cleaned and greased it because of an intermittent ignition . I couldn't even get mine to start or run.

Heres a handy guide I did earlier this year to stripping and cleaning the ignition switch.
http://www.xs650.com/threads/ignition-switch-overhaul.46712/

Its easy enough to bypass the ignition switch to either identify or eliminate it as the culpret. There is a large guage short red wire and connector running from the battery to the fuse box which can be unplugged... to act as a ignition on/off switch then simply bypass the ignition switch in the ignition switch electrical connector.

 

[chrispunk]

This is pretty old now but did you find a solution?

I’m having the same problem and have a Boyer. Bike cuts out while riding but doesn’t seem to lose power.

Won’t bump start while I’m rolling once it’s cut out and you can kick it all day it won’t start again unless you turn it off and on again when it will the start easily first kick.

Like you said it seems like the ignition unit needs to be “reset”

 

[Niels Mouthaan]

Replaced my Boyer ignition and the problem was solved .

 

[chrispunk]

thars What I thought, I’ll order a new one now.

Thanks

 

[peanut]

This is pretty old now but did you find a solution?

I’m having the same problem and have a Boyer. Bike cuts out while riding but doesn’t seem to lose power.

Won’t bump start while I’m rolling once it’s cut out and you can kick it all day it won’t start again unless you turn it off and on again when it will the start easily first kick.

Like you said it seems like the ignition unit needs to be “reset”

Boyer Bransden electronic ignitions are probably the most reliable electronic ignition system you can buy for your bike.
I believe the guy invented them !

If you are convinced it is the Boyer then give their technical dept a ring they are very helpful and can diagnose your fault and supply a replacement if necessary.
http://www.boyerbransden.com

Its extremely unlikely to be the Boyer it sounds like a bad ground or electrical connection somewhere possibly the
the ignition switch as the internal contacts oxidize .

If your ignition light comes on slowly or flickers when you wiggle the key then that would confirm it.

Also check the connections and wiring in the fuse box and inside the headlight. Check the connections and wiring in the stop switch

Make sure that your battery is holding a good charge and the charging system is ok . When the engine cuts out how bright are your lights ?

 

[chrispunk]

The engine cuts out regardless of if the lights are on or not. The battery and charging system are brand new and working well. The ignition switch is also new so the chances of it being oxidised are slim.

The Boyer is old, was on the bike when I got it.

The only patern I can see is it seems like it usually happens on deceleration/low speed. Which Initialy made me think it was a battery issue but a new bigger battery has not help the situation.

I’ve been through the wiring and all
The connections seem good. Also a bad connection wouldn’t be “fixed” by power cycling.

I’ve just seen this on the Boyer site though.


“Why Do I Need To Use Suppressed Plug Caps?
MKIII and MKIV do not require suppressed plug caps for operation although we recommend using supressed 5000 ohm plug caps. Micro Digital and Micro Power units must be fitted with supressed plug caps. Plug caps fitted with suppression resistors are usually fitted to prevent radio interference. Radio interference (noise) can cause more complex electronic circuits like radios and computers to malfunction.

Our Micro Digital and Micro Power ignition systems contain a small computer operating at high speed that can be adversely affected by radio frequency interference. Symptoms can range from refusal to start to intermittent engine stalling symptoms. Use of non-suppressed plug caps has been known to cause permanent damage to the ignition unit”


Im not sure what caps I have on. I don’t think the Xs has resistor caps stock does it?