Whats the best spark plug???Does it really matter??
Seasoned HDF Member
Joined: Sep 2009
Posts: 25,310
Likes: 2,446
From: Eastern NE
If your bike's a '10 & doesn't have any problem(s) w/current plugs - no need to change. They last forever & HD's are just fine. Not going to see alot of performance increase w/plugs...
Road Master
Joined: Aug 2007
Posts: 1,049
Likes: 5
From: Emerald Coast, FL
As far as spark plug technology goes there is probably not much difference between a regular ol' plug and a new concept plug other than the metals used now in the more expensive plugs doesn't tend to pit out as fast if at all like it does in a regular plug.
If you don't want to or can't figure out how to "tune" your plugs... just don't. If it makes you feel better about yourself to criticize those that do "tune" 'em... great!
Road Master
Joined: Aug 2007
Posts: 1,049
Likes: 5
From: Emerald Coast, FL
Yep... I would know that I am getting a spark plug built to minimum specs by the lowest bidder. NO THANKS!
Road Master
Joined: Aug 2006
Posts: 1,148
Likes: 157
From: Banning, CA
NGK Iridium Plug
For late/ peanut plugs the number is DR7EIX for NGK Iridium plugs. Be forewarned
that their internal resistance is 5K ohms vs. 20K for HD plugs. If you have a carb
motor it makes no difference but injected HD's knock sensor will be inoperative if
you use them - google "harley ion sensing" for definative operational parameters.
BTW - Denso Iridiums are about 6K ohms so no difference there. IMHO.
that their internal resistance is 5K ohms vs. 20K for HD plugs. If you have a carb
motor it makes no difference but injected HD's knock sensor will be inoperative if
you use them - google "harley ion sensing" for definative operational parameters.
BTW - Denso Iridiums are about 6K ohms so no difference there. IMHO.
Elite HDF Member
Joined: Dec 2010
Posts: 4,501
Likes: 26
From: Sheboygan,Wi
These day it would have been a Pro Mod (70 Olds 442) but back when Dad and I had it running it ran IHRA Top Sportsman. After a rebuild and Nitros added the car made it's first ran as a Pro Mod in Fremont,Ca 1998 1/4 mile time was a 5.8 231 MPH second run hand granaded the engine and rolled the car. Dad still runs Outlaw Street but I have since moved on and can't afford that hobby.
Road Master
Joined: Aug 2006
Posts: 1,148
Likes: 157
From: Banning, CA
HD spark plugs
mechanics, makes all the MoCo plugs and quality control is all over the place.
Before posting about HD's unique 20k ohm plug, I went and physically measured
the resistance in 1) stock HD 6R12 2) NGK iridium DR7EIX 3) Denso iridium IXU22
and 4) new off the shelf HD 6R12PP double platinum @ $8 each. Results were
1) used stock 22k 2) used NGK 5k 3) used Denso 6k and NEW HD's - one was
20k and the other one 83k ohms / N*F*G - yep, brand new in the box and ya
can't return electrical. Yes, I'll go get another but will take my meter with me.
So much for MoCo's most expensive plug. BTW - HD sez this plug has antiseize
on it - not that I could tell.
Outstanding HDF Member
Joined: Jun 2007
Posts: 2,796
Likes: 36
From: Toronto, Ontario
Dude,
You are making sense ?.. that is not fun ..
to the Ops...
You are making sense ?.. that is not fun ..
to the Ops...
wow some guys go crazy with this stuff . seems like a lot of trouble on something that means so little. I guess if my pink slip was on the line i would take notice but in this case i would have to pass on the indexing i may go with the plugs but that's about it. I have a built motor and i like having a little extra power but its all about ego. I said this before and ill say it again it means nothing if you dont have the ***** to use it and if you cant handle it. there is really no where on the roads around here where i can feel safe really letting it go. i can be on a route and doing 100 mph and some jerk will fly out of a side road. or on the freeway coming out of third gear at close to 100mph and there is a big fat state police. like i said i like the extra power but some of it is just ego. I got a buddy who has an older bike softail its built to the max stroker and all its great for bar hoping and corner to corner but that is about it. he is not taking it on no 300 mile ride and if he really cracks that thing there is no telling what will happen.i guess i am getting old or maybe wise in my old age
Grand HDF Member
Joined: May 2008
Posts: 4,624
Likes: 189
From: Newcastle, Ca.
If your bike is properly tuned the exhaust 2 into 1 or 2 into 2 makes no difference... the back pressure and everything else concerning exhaust can be set to exactly the same specs. 2 into 1 is a look that is starting to come back around dating from the 60's. The exhaust manufacturers have run out of "unique" 2 into 2 looks so to pander to the market with a different look, they have retro marketed back to a 2 into 1 look.
Back to the plugs. Stock plugs work fine and are an important piece of the anti knock ion sensing built into the ecm. Another plug may or may not effect the system. Its your call, your bike, your pings
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Road Master
Joined: Aug 2006
Posts: 1,148
Likes: 157
From: Banning, CA
will not work with 5k ohm, the standard resistance for resistor spark plugs.
Seasoned HDF Member
Joined: Oct 2006
Posts: 5,977
Likes: 85
From: Nevada
I've never had an issue with NGK, Autolite, Champion. Also have used NGK Iridiums.
I wonder if a properly tuned motor even needs the knock detection.