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can any one tell me if the 2 mounting points on each of the coils witch bolt it to the frame do any thing electrical. They do look like some kind of earth points iam trying to get to the bottom of my running problem and ive been looking tonight and some of the mounting points where really rusty ive cleaned them up but was wondering if these could have any thing to do with it running bad its got a miss fire or something like that ? and iam trying to eliminate as many possable problems before rebuiling ive allso changed a few male connections that looked rusty
thnks kev

No they don't the earths are on the back of the engine near the crankcase breather and onto where the frame is at the rear shock area.

However, i would make sure your HT leads are not cracked and the caps are screwed in properly. Whats the running problems?

its spluttering around 5000rpm its not to bad if your riding it like you stole it but when you try to ride it normal it just splutters its hard to tell if its miss firing or what. how do you know if its miss firing can you use them light things that go on the plug cap lol ive no idea thanks

hehehe "light things "

if you watch the flashes you can usually notice a miss realy clearley, also are you running std airbox/carbs?

Unless you have already done it - I would start with a good clean of the carbs - make sure no toad in the float bowls etc - blow thorugh the jets and make sure the spluttering isnt to do with the carbs.

has the problem always been there? i.e. a fueling flat spot.

Changed the spark plugs recently? Serviced it recently?

Coils do ground onto the frame so make sure where they bolt onto is clean !

No harm in running an additional earth lead from the mounting posts down to the earth on your battery - done this on my ZRX and will be doing it on the ZXR too.

Check your carb's like Dave said too

MM!

Coils do not ground to the frame. The coil has a +12v common ign feed and the ground of the coil is what is switched by the igniter. The only ground return for the coil is through the PLUG to the head and back through the earth strap on the block. So no the two bolts definately have no electrical connection to the frame....cheers

kind regards TK400

Tell you what mate,

Undo your coils and zip tie them "floating" seeing as they are only bolted to your frame "pretty"

Kind Regards,

Drew.

i thoought they earthed through the frame too, hence where the bolt goes through the coil its metal!! mine are anyway

No the coils are definately not earthed to the frame. The bike would not run as the negative side of the coil is the side which the Igniter switches to charge the coil. It is the 12V side that is held at a constant voltage. You can test this by earthing your negative side of the COIL. this will kill the ignition just like on a dirt bike. cheers

regards TK400

@Drew, etc...

a) My bike runs fine with the coils just sat loose on top of the engine.

b) Take a closer look where they screw into the frame, they are actually screwed into rubber bushes. That's going to provide really good earthing

might have rubber bushes but the threads of the bolt actually screw into the frame

No.

They screw into brass inserts which are moulded into rubber bushes. Except on my bike, where the inserts have fallen out of the bushes, which is why one of the coils is just sat on top of the head at the mo.

And it still runs.

mine bolts straight to the frame, not disputing youre runs fine,
answer me this though,
how come the whole outside of the coil is plastic, but, the bit the bolt goes through is metal?