Author Topic: Faulty Plug Leads  (Read 2227 times)

Offline basadia

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Faulty Plug Leads
« on: October 24, 2015, 02:10:36 PM »
I've noticed that I'm changing plugs about every 5000 k's as my bike is developing a low speed miss and I'm not sure why. When the motor gets above 1500 RPM the miss disapears and it does not show under load. I've read that plug lead caps have a resister inbuilt and that the resistance should be around 5000 ohms when on a multi meter, I've tested two and they both are within spec but the other two won't read on the multi meter so I'm guessing that the plugs are failing due to this. I've priced replacement caps and they are about $27, what I'd rather do is replace the resistors but am not sure where they could be sourced.
I am also thinking that I could just cover them with aluminium foil in the same way that you can cover fuses in an emergency to get you to the nearest supplier. I'm not sure if this could damage any of the electronics though.
Anyone able to advise?
TAI

Keith
Keith
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Offline Gadget

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Re: Faulty Plug Leads
« Reply #1 on: October 24, 2015, 02:31:51 PM »
The resistors are normally mpoulded into the leads.   Because of the high voltages you best just replace them, because any gaps in the insulation will cause sparks to jump across to the chassis and reduce speak effectiveness.
Cheers,
Gary
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Offline basadia

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Re: Faulty Plug Leads
« Reply #2 on: October 24, 2015, 02:55:30 PM »
You can pull the plug cap apart, it is a flat blade screw inside the plug side of the cap and the resister and the cap fitting come out. The resister is about the same shape as a glass fuse and is very easy to replace and probably would be much cheaper than replacing the full cap. Full set of plug caps would be about $120 4 resisters could not be more than about $20 if I could find someone to supply them.
Keith
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Re: Faulty Plug Leads
« Reply #3 on: October 24, 2015, 04:01:33 PM »
You can pull the plug cap apart, it is a flat blade screw inside the plug side of the cap and the resister and the cap fitting come out. The resister is about the same shape as a glass fuse and is very easy to replace and probably would be much cheaper than replacing the full cap. Full set of plug caps would be about $120 4 resisters could not be more than about $20 if I could find someone to supply them.
There you go. Handy to know.
Cheers,
Gary
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Offline basadia

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Re: Faulty Plug Leads
« Reply #4 on: November 05, 2015, 08:45:20 AM »
So I have changed the plug caps and I still have the miss which has now developed into a popping which is audible through the exhaust and the air box. I suspect that I have a faulty lead or maybe coil. I found a full set of leads and coil packs on Epray for $75 so I have ordered the set. I figure by the time I replace all the electrics genuine it's going to cost me a fortune.

Looking at the Clymer manual it sais to do a resistance test through the coil on the plug leads one with the caps on and one with them off but the referenced table is a bit vague on what the reading should be for both tests. Can anyone assist with what the resistance readings should be?

tks
Keith
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Online Brock

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Re: Faulty Plug Leads
« Reply #5 on: November 05, 2015, 05:28:30 PM »
Have you looked at the manual we have online. its the first topic in the 1100 section.
Brock
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Offline STeveo

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Re: Faulty Plug Leads
« Reply #6 on: November 05, 2015, 05:53:51 PM »
Have you checked your valve clearances lately?