Spark Plugs Recommended? - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
Electrical
Where does this wire go?
Includes Electrical mods, Lights, Stator,
Rectifier, Diagrams, etc

 
LinkBack Thread Tools Display Modes
post #1 of 6 (permalink) Old 05-21-2019, 04:19 PM Thread Starter
Senior Member
 
Jason Pittenger's Avatar
 
Join Date: Apr 2018
Location: Northern Illinois (Not Chicago)
Posts: 231
iTrader: (0)
 
Garage
Spark Plugs Recommended?

I'm considering a new set of plugs. I'm over 21,000 miles and no idea if these are the original plugs or not. I've heard the NGK Iridium IX plugs (DPR7EIX9) are an improvement over the stock plugs (DPR7EA9). Is there a noticeable improvement, or is it just the advantage of having lifetime plugs in the bike?

Has anyone tried Denso Iridium Power (IX22B) plugs? This was the cross-reference on the Denso website. They have a U-shaped ground electrode, claiming better flame kernel growth. https://www.denso.com/global/en/prod...wer/index.html

I'm also curious about Denso's TT plugs.
https://www.denso.com/global/en/prod...lug/iridiumtt/
They have Iridium tips on both the center and the ground electrode. The realistic advantage I could see here, is our two plugs fire in opposite electrical polarities. By that, I mean one plug has a very high positive voltage on the center electrode, and the other plug has a very high negative voltage on the center electrode. The spark travels in opposite directions in the two plugs. The TT claims to be designed for bi-directional spark travel, vs standard shaped plugs.

Regarding twin tip plugs in general, I found this on Advanced Auto's website https://shop.advanceautoparts.com/r/...en-spark-plugs

"Double platinum spark plugs were designed for 'waste spark' DIS. In a waste spark system, the spark jumps from the center electrode to the side electrode for the cylinder that’s on the compression stroke. To return the electrical pulse back to the ignition coil pack, the spark jumps backwards (side-to-center) on the partner cylinder. Since the partner cylinder is on its exhaust stroke, nothing ignites and the spark is 'wasted.' You can’t use single platinum spark plugs or traditional copper spark plugs in these systems because the side electrodes aren’t designed to handle the reverse spark. But double platinum spark plugs, with a platinum disc welded to their side electrode, work exceptionally well. Both the center and side platinum discs remain sharp, allowing sparks to fly easily in both directions without causing rapid electrode wear."

That seems like it would be an advantage here, but I don't know if it's just hype.

I don't have a part number for the Iridium TT plugs. The cross-reference only pointed me to the Iridium Power plugs.


'89 Vulcan 750 Bought 4/12/18 @ 17805.9 miles $800
Purchased stock. Wrecked once
22490.0+ miles

Completed modifications:
Removed mufflers, straight pipes out of GB
110/90 Front Tire
Pick-up coil re-gapped to .020"
Compufire 55402 r/r series regulator
USB Outlet + Voltmeter
Repainted Metallic Blue w/ new tank bages
Ear Shave (wo/ coasters) 40/140 NO shims 45MPG
MCCT conversion

Planned modifications:
Custom LED turn signals
Windshield
Highway Pegs
(Possible) ignition advance

Last edited by Jason Pittenger; 05-21-2019 at 04:23 PM. Reason: Added last two sentences
Jason Pittenger is offline  
Sponsored Links
Advertisement
 
post #2 of 6 (permalink) Old 05-21-2019, 09:12 PM Thread Starter
Senior Member
 
Jason Pittenger's Avatar
 
Join Date: Apr 2018
Location: Northern Illinois (Not Chicago)
Posts: 231
iTrader: (0)
 
Garage
I thought about this more on my way home. Both iridium and iridium TT spark plugs claim a faster flame growth. Basically and effectively, it seems like it advances the ignition slightly. Assuming it doesn't cause knock, that would provide more power and more fuel economy. Couldn't I get the same results with a manual ignition advance? I wonder if that is all of where the advantage comes from, is the faster start of the flame front.

They also claim that the plugs changed the shape of the flame, which could not be duplicated with an ignition Advance. The flame appears to travel downward better, based on their literature.

There is definitely also the lifetime advantage of iridium. And, the TT does have the bi-directional capability that no other plug does quite as well.


'89 Vulcan 750 Bought 4/12/18 @ 17805.9 miles $800
Purchased stock. Wrecked once
22490.0+ miles

Completed modifications:
Removed mufflers, straight pipes out of GB
110/90 Front Tire
Pick-up coil re-gapped to .020"
Compufire 55402 r/r series regulator
USB Outlet + Voltmeter
Repainted Metallic Blue w/ new tank bages
Ear Shave (wo/ coasters) 40/140 NO shims 45MPG
MCCT conversion

Planned modifications:
Custom LED turn signals
Windshield
Highway Pegs
(Possible) ignition advance
Jason Pittenger is offline  
post #3 of 6 (permalink) Old 05-21-2019, 11:28 PM
Retired USAF (IYAAYAS)
 
Chris and Shim's Avatar
 
Join Date: Mar 2010
Location: Fredrickson Wa
Posts: 604
iTrader: (0)
 
Garage
I never felt any difference with my plugs but that doesn't mean there's not an improvement. About the only thing I can report is my bike seems to crank pretty easily.

TOC MCCTs
Saddlebags, hard mounted
Fork mounted tool bag (now hard mounted)
Relocated rear turn signals
LED turn signals, brake lights and running lights
LED license plate frame
Engine Guard and Highway pegs
National Cycles Low Boy Heavy Duty windshield
Home made lowers (nice)
Custom seat (made by a local guy)
Iridium plugs (DPR7EIX-9)
Shenko 230 Tour Master tires at 11,123 miles
Splines lubed at 11,123 miles
Luggage rack
Light bar with LED lights
Chris and Shim is offline  
 
post #4 of 6 (permalink) Old 05-22-2019, 04:19 PM
Members who have donated towards server costs
 
flitecontrol's Avatar
 
Join Date: Dec 2008
Location: Monroe, LA
Posts: 4,696
iTrader: (14)
 
Advantages are the electrode doesn't wear much, if at all, meaning the plugs don't need to be periodically re-gapped or replaced, they are cheaper, over their lifetime, than regular plugs and they provide a consistently good spark. It's doubtful that they provide any significant performance enhancement over fresh, standard plugs, in spite of advertising hype to the contrary.

I'm keepin' all the left over parts. I'm gonna use 'em to build another bike!
_____________________________________________
"Black Beauty"
1989 VN750 acquired December, 2008, 6,711 miles
Currently 23,298 miles

Old Blue
2001 Honda CMX250 Rebel acquired July, 2008

1987 VN750 project bike, acquired August, 2009, 33,000 miles and balancer sticking out of the case, currently awaiting attention and parts
flitecontrol is offline  
post #5 of 6 (permalink) Old 05-22-2019, 09:22 PM
I'm a rider
 
One1's Avatar
 
Join Date: May 2014
Location: Signal Mountain, TN
Posts: 764
iTrader: (0)
 
Garage
Old simple bikes like old simple plugs. /end

I have a CJ7 that pretty much refuses to run on anything but cheap ac delco plugs. That’s what the 258 was designed for, that’s what it likes.


1981 KZ750
1988 Vulcan VN750 (red)
2005 Vulcan VN750 (silver)
(2) 1994 Vulcan VN750 (red)

Engineering solutions for the VN750 Community.
One1 is offline  
post #6 of 6 (permalink) Old 05-23-2019, 05:32 PM
Members who have donated towards server costs
 
Join Date: Nov 2007
Location: Chandler, Arizona
Posts: 2,841
iTrader: (0)
 
As far as starting, the Vulcan 750 has always been hard to start. I tried the expensive iridium plugs, and noticed no difference. I have noticed that the Vulcan engine turns over slower than on every other bike I've ever had. I did take the starter apart on one and it was filthy inside. I also replaced the brushes. But the cranking speed did not increase. I have connected it to a huge truck battery (12V) with way more amps than the Vulcan starter requires, it still turned over somewhat slowly. I noticed my Sportster does that too, but it has a really long stroke engine. The Vulcan has a short stroke engine, and it seems like it should turn over a lot faster than it does. Might be a design problem with the starter. Many inline fours turn over faster with the starter than they do when running at idle.

I am a motorcyclist, NOT a biker.


1997 Vulcan 750, purchased about a week ago
2006 Sportster 1200 Low
2013 Royal Enfield Bullet 500, converted to carb
2001 Yamaha XT225, heavily modified
2004 Honda Rebel 250
1979 Vespa P200E
2002 Vulcan 750 parts bike
1994 Yamaha XT225 parts bike
VN750Rider/Jerry is offline  
Sponsored Links
Advertisement
 
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Once registered, your User Name"cannot be changed". We can make exceptions within 7 days, but after that, it is set in stone.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome