Hi all,

Having issues with the 400, seemingly no spark. Manifested itself earlier in the year, but I have only just got around to looking at it.

Problem started one evening heading home, noticed a loss of power and had to increase throttle input to get any power out of the motor. This got worse and worse, so I pulled to the side of the road to investigate. Bike stank of petrol as I had effectively been trundling along with WoT. Eventually coaxed the bike home with a lot of clutch slip, threw the cover on it in disgust and forgot about it.

Fast forward to Saturday, I strip her down to check the plugs (New set in hand), and before fitting them test a new plug on the HT leads. Absolutely no spark at all. This is with a brand new battery which I installed beforehand. I plan to start trouble shooting by investigating the;

Kill Switch
Coils
CDI
(Checked all fuses and connectors, seem fine, but not put a meter on them yet)

Now with the initial symptoms of the rough running (Which I am assuming was the spark getting weaker and weaker), can you suggest the best place to start or any known issues? Bike turns over fine, and other electrical systems seem fine.

Cheers

i would first check the regulator as it kills easily and gives the symptoms you describe,could be coils breaking down as well (as they do when hot).if you need any of those parts i have them for sale,so good luck and let us know how you get on.

you dont need to have the regulator connected to get the bike running but a test of the electrical system should be in order when you do get it running as what was stated above can happen, if your reg/rec fails then it can over-charge the system and cook the ignition box etc.

Were you connecting the plug to the engine when testing for a spark? If you remove the plug and stick a long nail or bolt in the cap and hold it close to the frame you can check for a spark that way.

If still no go next port of call would be to check you have power to the coils with a multimter.

since you hav ea new fully charged battery its unlikely to be suspect but check all fuses and connections too, especially from the pickup coils to the loom / ecu.

side-stand switch / kill swith can also cause no spark.. were you testing it with side-stand down?

the acuall running issue is odd.. it could be electircal, it could be vaccum hose / fuel tap failure cutting the fuell off.

rough plan of action should it be my bike were.

1. check obviousl kill switch / side stand.
2. check for sprak with / without plugs
3. check for power at coils
4. check connection from coils to ecu / check coils resistance as per service manual.
5. swap ecu if coils have power and everythign in check.
6. fire it up without reg/rec and test output from genny. then connect reg/rec and check output from that too.
7. insepct vaccum pipe / fuel tap

or something like that.. sure youl get it going again.

sounds like when my stator burnt out - check the voltage across the battery with the bike running should be around 14.5V when revved, if it's much less or much more you've got some reg/rec (e.g. 19V) or stator issues (< 10V)

Thanks chaps.

As soon as it stops raining, I'll try and get some time to troubleshoot.

To rule out the charging system, simply easier to disconnect the Reg/Rec? Battery is brand new and fully charged so I'll have amps to play with.

sounds like a good idea.

assume you have lights on the dash with the ignition on? (main 30A fuse went when my reg/rec had an issue)

Badgerboy wrote:Thanks chaps.

As soon as it stops raining, I'll try and get some time to troubleshoot.

To rule out the charging system, simply easier to disconnect the Reg/Rec? Battery is brand new and fully charged so I'll have amps to play with.

Neosophist wrote:you dont need to have the regulator connected to get the bike running but a test of the electrical system should be in order when you do get it running as what was stated above can happen, if your reg/rec fails then it can over-charge the system and cook the ignition box etc.

as per my first line.

You dont need it connected to get it running, it will also isolate the charging system from the bike.. a fresh battery without headlights on should run the bike for at least 30 mins probably longer.

Check your coils. I'm replacing mine and wires since i got a jolt yesterday. Same symptoms as yours found out i was getting arc off the frame.