Cops/ plug type / gap

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Ost85vmax

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I know all this info is out there but...

Can anyone help me with the recommended plug and gap when using cops with no resistors on an 85 electrical setup. Thanks.
 
It should be .035. Normally it's the resistors in place that make the plug gap to have to shrink.

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Yeah sounds like stock plugs are the answer. I know I have iridium plugs now but going to go with stock next. I seem to be having some mpg issues. Only getting 26 so I am starting with some new properly gapped plugs to start.
 
'85. Unresistored COPS. Plugs at least 5 years old, set to whatever the manual told me to set them at. At least 40mpg, and it runs like a bear. To my way of thinking, fuel consumption is ( assuming no carb changes made..) determined by throttle position and RPM. Unless a gap change causes the engine to run with less power, necessitating more throttle for the same power output I can't see why the motor would need more or less fuel.
 
Did you mean 147.5?

Nope- 157.5 I am almost below sea level.
I just pulled out 152.5 and put in 155 with iridiums- then went to stock plugs with 157.5
I have gone 88 miles 3 times now and can only get 2 gallons on fill up each time.
 
My 2000 with COPs (88vmx12 leads with resistors and Denso 129700-4400 COPs) and stock NGK's gapped at .026 have consistently given me 36-38 mpg unless I am really getting on the throttle, then I get about 25-28 mpg.
I've put about 8-10k miles on my Vmax since I installed the COPs mod.
 
My 2000 with COPs (88vmx12 leads with resistors and Denso 129700-4400 COPs) and stock NGK's gapped at .026 have consistently given me 36-38 mpg unless I am really getting on the throttle, then I get about 25-28 mpg.
I've put about 8-10k miles on my Vmax since I installed the COPs mod.

Exact same same cops i have 05-06 gsxr 750 with 07-08 R1 harness. Same denso numbers.
When i did the cops myself i put iridiums gapped at .027 and got 41mpg- changed to stock ngk's that were factory .032 and got 42mpg
Gapped a new set at .038 and now 44mpg.
Bike has 12,000 total miles on it.
 
I read somewhere that they should be gapped at .026 when using COPs but must have missed the resistor part.

First off, I assume I dont have resistors as I dont see them on the wire connector. (Bought from Gannon but this was before I added the Dynatek 3000)
Second, should I be running with resistors if I have the Dynatek 3000? Its a 1994 bike.
Lastly, whats the effect on the bike being gapped at .026 versus .035 for non-resistor COPs?

Thanks
 
Well theoretically the bigger plug gap will help with burning fuel. Yes....I have been told to always run resistors with the dyna 3000. Some people have burned theirs up in just a couple hundred miles.

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