wont accelerate, coughs and stops...?

[benlawlor85]

Hi barry,
thats what i was thinking, im pretty sure its staying engaged. any idea where to get parts to rebuild it? as in the washer. im assuming the hall sensor etc is fine.

Also i have just found the connector that  the wires from the startermotor/soilnoid to the coil (LT circuit) was quite corroded. think ill just buy a new connector and put  that one. is with worth replacing the wiring too?

[tvrla]

It's highly likely something changed with the recent work, so that's the first and best place to look.

By the way - I can't really tell what changed between the time it was starting to when it didn't?

Most immediate problem is the HT end. Those are normally soldered on, so that's easy. Dig the clip out of the coil socket, whittle back a little of the insulation and solder it back onto the lead. Make sure the socket is bright and shiny copper for the best connection.

If you have a multimeter, take an ohm reading from one lead to the other straight through the spark plug caps - should be somewhere around fifteen to twenty thousand ohms.

Do the spark plugs spark when cranking the engine?

I doubt the carburetors suddenly stopped working - unless they're not getting any fuel. So rather than getting upset, tearing your hair out, and pulling the bike apart looking for something obviously broken, it's best to routinely walk through troubleshooting steps to locate the problem. Gotta be smart about this - the shotgun approach is kind of crude and may work sometimes, but not enough to give any real satisfaction. And besides, it can be really expensive buying un-needed new parts.

I don't follow you on the black washer around the prongs. But there is a test for the bean can, but it does require constructing a simple circuit with a light bulb and resistor. Or it can be tested when installed. One of the easiest methods is to disconnect the plug to the bean can and then with the ignition on, ground the center terminal. If the spark plugs spark, when they didn't before, the bean can is bad.

[montmil]

... One of the easiest methods is to disconnect the plug to the bean can and then with the ignition on, ground the center terminal. If the spark plugs spark, when they didn't before, the bean can is bad.

Use the terminal block coming from the engine area, not the three-pronger from the ITU.

Pull and securely ground the plugs to the cylinders. A paperclip can be used as a jumper. With ignition on, touch the end to a ground point on the chassis and each time you touch, the plug should spark. No worries, it's won't shock you. Also, confirm the handlebar ignition toggle switch is in the run position.

Mongo

[benlawlor85]

Hi all.
 no spark,
did the test still no spark.
Will order coil and HT leads tomorrow.
and fingers crossed the Timing sensor is ok.


Ben

[tvrla]

Whoah... we still haven't determined the coil is bad - so let's not jump to conclusions!

What we determined was that the bean can isn't necessarily bad. Sometimes more than one thing can fail, and until it's proven good, it's suspect. Anyway, the test showed you're not getting a spark when the ignition is told to spark (that's what the bean can does).

The ignition system contains the control unit (really just an amplifier) and the coil. The coil is easier to test so...

Let's test the coil. Ok?

Make sure the coil has +12V coming to it.

The other coil terminal goes to the control, and when the bean can says "SPARK!" the control until gives the command to the coil.

To make this all as simple as possible to explain, the spark plugs spark when the coil is grounded. The bean can makes a ground connection at the right time, the amplifier magnifies that ground and gives it to the coil - and you have  S P A R K !!!!

So, all you have to do is ground the other terminal (the one that doesn't have +12V, and the plugs should S P A R K !!!

Do that and let us know what you find.

You see - it's just possible you'd install a new coil and still not have a spark because the real fault is somewhere else - like the kill switch or the wiring somewhere.

[benlawlor85]

The coil is known to be bad. its where the original problem started.
The bean can issue was just me being stupid and not refitting it properly!

thanks for the info tho its interesting to know whats going on in there!!.
Ill try what you have suggested that tomorrow.

Ben

[Sergeant_Joe]

Have you looked at the two fuses under the rear of the tank? you may have shorted one out when you was fixing stuff.

[tvrla]

But the ignition isn't fused... at least that's my recollection.

[Bob_Roller]

The ignition is on a circuit protected with a fuse .

I think the only circuit that doesn't go through a fuse, is the headlight .

[Sergeant_Joe]

I would be starting at the Battery and checking the live feed from there all the way to the spark plugs, find out at what point does the live 12 volt feed stop. If you have power right up too the coil but not after you can then say it's the coil, if power only up till the been can then problem may be here ect ect. but always look at the little things like fusses, batteries and earth grounds first. I had a mate bring me his bike out of frustraition once, he had replaced most of the big expensive stuff and still it would not run, I looked it over and found that his main earth was not good in contact. I resolderd it and turned the key and away it went . in Auto electricks the villan is the earthing 95% of the time.

[tvrla]

Definitely! Don't ignore the grounds. It's really common to assume the hot side is the important one and so only pay attention to them. But the ground is every bit as important, so neglect at your own risk!

[benlawlor85]

Hi,
thanks for all the responses. Fuses are blade type and in a housing and are fine. battery earth is fine (i think) bike turns over nice and fast. a few of the corroded contacts is what is troubling me at the moment. I think the best way maybe to just replace them with euro style connectors while replacing most of the LT circuit at the same time.
One thing that i have always found strange is how small the wires are in these bikes yet have a relatively powerful electrical system.

Will give an update later.
off to work now.



ON THE BUS!!!!!

:-(

[benlawlor85]

OK. so this gets a little odder. i came home to try the same test as i did last night, ground the centre pin that goes to the timing sensor, and she sparked away! So i decided to try and start her, and she started! great i think.... quick turn of teh timing sensor and she was running ok...

I then notice the GEN light is on!!! Great! one problem to another.

The tests i have done so far.  regulator off and blue/black wires jumped, light comes on. also tried a spare regulator i had from my old R80, same thing.

Short the two slip rings on the rotor, light stays on.

Ground the DF brush on stator, stays on. (but goes off when its not connected or grounded)

Im a little confused now. I swapped the diode board with the spare, again from the R80 no change.

also there is no charge going to battery when bike runs. stays at about 12.5v

any help as always would be greatly appreciated.

oh i have also cleaned many contacts that were corroded and squirted battery terminal stuff on them.

Ben

[Sergeant_Joe]

OK so the problem in my mind seems to realy be low battery charge.
Your stock system is having trouble keeping it up .
1) How long are your alt brushes (if in doubt swap em out).
2) The earth from diaod board too engine case is bad on these bikes (to overcome low charge on mine I ran an earth wire from Neg side of dioad board too the little bolt that holds the starter motor in).
3) I also put a earth wire from the Neg battery termanal up to a bolt on the rear frame, all charging issues fixed.
4) For it not to work one day and then work the next is telling me you have a loose or intermitant earth conection ie the curcuit is being inturupted by the bike being moved ect.
5) One more thing that can help is to fit an adjustable regulator and set it by hand to 14 volt.
6) Allso remember that these bikes don't start putting out charge till they reach 2 or 3thousand RPM, so low revs in the shed will slowly kill battery charge.

[benlawlor85]

Hi Joe,
Battery is on order should be hear tomorrow, the old one has been on a C-tek which is why im assuming the bike started today!

I replaced the Brushes and springs the other day as a matter of course.

I will double check the earthing on the diode board.
Is there anyway to check if there is any power coming from the alternator?
Im just very confused on this problem as everything with the charging system was fine before!

Ben