New postby Gerrit » Sat Feb 12, 2011 8:14 pm
Replace the Spark Plug caps
"I was battling with a intermittent misfire for months, and eventually, I found the problem in the Spark Plug Caps.
There is a resistor in the cap, that fails, and causes all the drama.
I replaced mine with NGK caps, and the bike has never been better.
Have a look at the photo below...if you remove the rubber sheath, you can unscrew the cap, to reveal the resistor and the spring that conducts the current down to the plug.
The spring was corroded and the resistor was dead.
me thinks this is a fix to many peoples problems."
The problem with the standard plug caps is removing them after say 8000 miles when you want to replace the plugs. I used a pair of pliers in desperation and in so doing I split the rubber - I didn't notice this at the time - however I think some water does get in especially after pressure washing - it misfires for a short time after until it warms up. I'd be inclined to fit new standard caps/leads just to keep the seals as I ride in all weather, with a dab of grease -silicon grease possibly - applied to the socket where the plug connects - this might make it easier to remove the cap when required.
methinks the resistor is there for a reason - it's part of the circuit.
taking it out will no doubt give a fatter spark but could possible damage the coil as that is then the only resistance in the circuit.
like you cant short out a mains wire, but you can if you put a light bulb between the wires, if you get what i mean....
You do not have to say anything. But it may harm your defence if you do not mention when posting something which you later rely on in quote. Anything you do say may be ripped to sh*t.
Benny lad,when you say "check for rust where the coil bolts to the frame" whats this mean then? one of my coils has never been bolted to the frame.Just wondering.