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Discussion Starter #1
Hi. I looked in the forum for this, and i found that G54V gives some problems with stalling. I have a F4 1000s. Days ago my bike was misfiring and was a spark. I changed CR9eix for G54V (i had a set at home). Bike runs ok, but cold start its very longer (here we have now around 7C in the morning). Next start ups are fast an normal, but first in the morning only possible in 3/4 attempts with full choke handle. Its normal with this surface gap sparks? Thanks to all.

Fernando.
 

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Surface gap plugs require a much higher voltage to fire cleanly. When cranking a cold engine the available voltage at the coil primary may be low causing intermittent spark.
I suspect that is the cause of your starting difficulty with cold engine/air temps compared to the iridium plugs you replaced.
 

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Discussion Starter #3
Thanks esq'z for your reply. Its possible that. I have a set of racing coil from a Fiat with 40k V output (same type coils). Its possible that coils will help or its better to go back to Iridiums? I will aprecciate your feedback. (Its easyer change coil that spark plugs). Regards.
 

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Is your bike a Maba? If so, kit or factory?
 

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Very nice bit of kit. What year is the 1000S donor?
 

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NIce. So, you have the early coil packs. Easy to check their operation.
 

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Discussion Starter #11
Coil are Marellis new. But maybe i will swap to racing ones. Only tank off. Plugs are a headache...
 

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Discussion Starter #12
Other thing im thinking its the Lithium Ballistic. I warm up with lights. Now i will try leaving the tender on until tomorrow morning and see if battery cold could be the cause. I Will update
 

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A very thin walled socket helps with the plugs, but you do have to get the airbox off, too. A bit more complicated.
You are thinking a more powerful coil will help with spark?
I would be tempted to go back to original plugs.
 

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Discussion Starter #14
A very thin walled socket helps with the plugs, but you do have to get the airbox off, too. A bit more complicated.
You are thinking a more powerful coil will help with spark?
I would be tempted to go back to original plugs.
Its a first thinking. I need to take off airbox, ducts and nose to change sparkplugs. First i will try with tender to check if cold lithium battery difficults starting. Then coil...and finally sparks. I wanted to know if anyone had problems with G54V in cold starting because it was option in SPR and Senna.
 

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Ah. Thanks for the explanation.
 

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A hotter coil will certainly provide more voltage to the plugs....but not if he battery can't supply the primary windings with adequate voltage.
We frequently upgraded to hotter coils on our race bikes in the 70's...stock coils on the Japanese bikes we raced were notoriously weak.
Cold LiPo battery ...or weak battery in general will reduce reserve voltage while starter is engaged.
Check voltage drop at battery during starting.
 
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Peluka;
Stop trying stupid stuff, go back to the CR-9EIX plugs
It's all about spark plug gap and the REAL energy the coils produce,
not the advertised energy
Ed, American cars used to use ballast resistors, the only time the coil
saw battery voltage was while starting.....you're right about motorcycle
coils being junk......$6.66 K Mart coils would jump a 31mm gap
After that the spark went through the phenolic top of the coil and the
rubber boot to jump to the coil ground terminal
Biggest spark gap I ever saw was a Joe Hunt Scintilla Vertex magneto @ 10,000rpm
jumping 8 INCHES the sparks made a deafening roar
Chuck, you don't need a thinwall plug wrench if you cut the valve cover
out of the way, I posted pictures years ago with wrench dimensions
 

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Discussion Starter #18
Thanks Knurl. Update: Today i tried with the tender all night. Now 3C . Started in a second after 20hs. So i presume lithium battery needs to be warm. Next change i Will put again NGKs. Btw i have a thin wall socket. I si mantenaine staff my self. Thanks to all. Kind regards.
 
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