Author Topic: Oh. So you've got a problem with the BLACK plugs?  (Read 1016 times)

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Offline SOHC4ever

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Oh. So you've got a problem with the BLACK plugs?
« on: July 17, 2009, 09:56:55 AM »
Bike is a 76 750F w/ a K3 motor, and BOY is it ever producing a pitiful spark.

I'm running the stock coils, points, and new DR8EA plugs. Now, I understand that these are colder plugs with a resister in them. I only run them because they were in the bike when I got it.

I'm running the stock carb settings, stock exhaust. I haven't done a proper plug chop, but whenever I pull them they're way too black.
The bike is properly timed, valves adjusted to spec. I'm thinking of switching to D7EA plugs and seeing how that goes before I start changing the needle positions. Thoughts? Any other 750 guys want to chime in on their plug choice for stock bikes?

The bike lives at sea level, in case that makes a difference.

Offline Gordon

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Re: Oh. So you've got a problem with the BLACK plugs?
« Reply #1 on: July 17, 2009, 10:02:49 AM »
Put in some new, non-resistor plugs and see what difference that makes before thinking about making other possibly unnecessary changes. 

Offline ev0lve

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Re: Oh. So you've got a problem with the BLACK plugs?
« Reply #2 on: July 17, 2009, 10:03:08 AM »
Same boat. Same question  ;D

Good tune, synced carbs, 1 1/4 turns on the air screws...

There was some talk of widening the gap (assuming you don't actually have pitiful spark) so as to get more burn with the D8EA's but if you decide to throw some 7s in there please report your results.

I'm coming up on my 1500 mile oil change sometime in August and I'll give the wider gap a shot then I think  ;D

Offline Cvillechopper

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Re: Oh. So you've got a problem with the BLACK plugs?
« Reply #3 on: July 17, 2009, 10:03:29 AM »
You need D8EA, not DR8EA.  You've got extra resistance in your current set-up.
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Offline mlinder

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Re: Oh. So you've got a problem with the BLACK plugs?
« Reply #4 on: July 17, 2009, 10:09:41 AM »
Bike is a 76 750F w/ a K3 motor, and BOY is it ever producing a pitiful spark.

I'm running the stock coils, points, and new DR8EA plugs. Now, I understand that these are colder plugs with a resister in them. I only run them because they were in the bike when I got it.

I'm running the stock carb settings, stock exhaust. I haven't done a proper plug chop, but whenever I pull them they're way too black.
The bike is properly timed, valves adjusted to spec. I'm thinking of switching to D7EA plugs and seeing how that goes before I start changing the needle positions. Thoughts? Any other 750 guys want to chime in on their plug choice for stock bikes?

The bike lives at sea level, in case that makes a difference.

You need d8ea. You are running resistor plugs. Hnce your poor spark.

/edit: beat me to it.
No.


Offline mystic_1

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Re: Oh. So you've got a problem with the BLACK plugs?
« Reply #5 on: July 17, 2009, 01:52:38 PM »
You need D8EA, not DR8EA.

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Offline hapakev

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Re: Oh. So you've got a problem with the BLACK plugs?
« Reply #6 on: July 17, 2009, 05:50:01 PM »
 :D LOLing.....Too Funny :D

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