coil stick

Kevinh61

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Nov 29, 2016
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High Wycombe , bucks, uk
so I went to have my rear brake pedal height adjusted , went to pick my bike up and had trouble starting it , coughed and spluttered and stunk of fuel , and stalled on way home , managed to get it back to the bike shop , he said it could be a fouled spark plug , so a few hours later they found out it was two of the coils sticking , they were in a right old state , so had all four changed along with the spark plugs , now running fine , but ouch not a cheap fix
 

Thrasherg

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Oct 16, 2017
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Location
Dallas, TX
Sorry to be stupid, but how does a coil stick? Are you referring to the ignition coils that create the high voltage for the spark plugs? Or some other coil? I can see an ignition coil going bad, but I can’t understand how it sticks or what that would mean? Just trying to understand.

Gary
 

Sierra1

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Nov 7, 2016
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Joshua TX
The coil is not sticking. It is referred to as a "coil stick". Or a coil-on-plug. The cost ranges from "not bad" to "holy s**t!".
 

Boris

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Dec 21, 2013
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midlands. UK
Kevinh61 said:
so I went to have my rear brake pedal height adjusted , went to pick my bike up and had trouble starting it , coughed and spluttered and stunk of fuel , and stalled on way home , managed to get it back to the bike shop , he said it could be a fouled spark plug , so a few hours later they found out it was two of the coils sticking , they were in a right old state , so had all four changed along with the spark plugs , now running fine , but ouch not a cheap fix
Hi Kevin

Which shop did the work?
 

Don in Lodi

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Ran fine when you took it in, and the coils went bad before you took it home? Strange.
 

worncog

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Aug 19, 2016
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Florida Panhandle
Not discounting all of the previous comments, cuz I was thinking the same thing, but stick coils do go bad occasionally. Two at one time though...hhmmm.

Had one go out on my C10 in the middle of a rally at a bonus stop. In-line four firing on three is a rough ride. Was fine cold, but once it warmed up the bad stick coil would misfire. Took a little head scratching to figure it out, since I had just refueled and initial indicators pointed toward fuel.
 

MIKE R

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Feb 5, 2012
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722
Location
Lancashire, UK
How old is your bike, what is the mileage and who serviced it?

The reason I ask is that I've found a very good local independent mechanic after not being impressed with 2 local authorised Yamaha dealers.

Although the Yam dealers had 'serviced' my bike at 12k (spark plug check) and 18k (spark plug replacement......became suspicious when he invoiced for 2 plugs) the ind was of the opinion when conducting the 18k service that the pugs had never been out and the coil sticks were starting to corrode. He cleaned them up as best he could and coated them in a protective grease.

Your failing coil stick could be down to poor servicing

Mike
 

stutrump

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Jul 25, 2013
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london uk
Handy tip from my mechanic friend. When you put new coild in remove the metal sleeve from around the coil. This is what corrodes on the S10 often resulting in the coil seizing in the s.plug hole area. We removed all the metal sleeves on my bike and its run fine for over 50,000 miles (since removing them). MUCH easier to get the coils out next time too!
Coils are available a bit cheaper from a shop in Cardiff on ebay. Think I paid about £50 each for mine
 

BelfastTen

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Jun 1, 2022
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3
Location
Northern Ireland
Handy tip from my mechanic friend. When you put new coild in remove the metal sleeve from around the coil. This is what corrodes on the S10 often resulting in the coil seizing in the s.plug hole area. We removed all the metal sleeves on my bike and its run fine for over 50,000 miles (since removing them). MUCH easier to get the coils out next time too!
Coils are available a bit cheaper from a shop in Cardiff on ebay. Think I paid about £50 each for mine
Does the shop you mention do online ordering?
 
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