Coils - Wrist Twisters
 
Thread Tools Display Modes
post #1 of 8 Old 08-11-2007, 09:19 PM Thread Starter
Discen
 
jclong74's Avatar
 
Join Date: Aug 2006
Location: St Louis, MO
Posts: 264
Rep Power: 1
 

Awards Showcase
Veteran 
Total Awards: 1

Coils

Has any one thought about &/or changed out the coils on the 919? It was a pretty popular when I had my 750. Would there be any benefits to doing it?

2006 919 (Sold)
2011 Cb1000r

"oh no there ain't no rest for the wicked, until we close our eyes for good." - Cage The Elephant
jclong74 is offline  
Sponsored Links
Advertisement
 
post #2 of 8 Old 08-12-2007, 08:51 AM
Old, Bold rider
 
robtharalson's Avatar
 
Join Date: Jan 2007
Location: Aurora, Colorado
Posts: 2,350
Rep Power: 1
 
Garage

Awards Showcase
Donation Veteran Community Leadership 
Total Awards: 3

Quote:
Originally Posted by jclong74 View Post
Has any one thought about &/or changed out the coils on the 919? It was a pretty popular when I had my 750. Would there be any benefits to doing it?
No benefit whatever. Ten years ago, sure: coils were so weak as to be laughable, especially considering that automotive coils of the same era were the equivalent of God's own lightning, able to jump the minor gap in the distributor and plug gaps in excess of .080". The ignitions in motorcycles have come a long way since then, so unless you are running a heavily modified engine or exotic fuels the stock coils are perfectly adequate.

Rob

robtharalson is offline  
post #3 of 8 Old 08-12-2007, 04:44 PM Thread Starter
Discen
 
jclong74's Avatar
 
Join Date: Aug 2006
Location: St Louis, MO
Posts: 264
Rep Power: 1
 

Awards Showcase
Veteran 
Total Awards: 1

Thanks

2006 919 (Sold)
2011 Cb1000r

"oh no there ain't no rest for the wicked, until we close our eyes for good." - Cage The Elephant
jclong74 is offline  
post #4 of 8 Old 08-12-2007, 06:24 PM
Cornicen
 
drivit's Avatar
 
Join Date: Apr 2006
Location: toronto
Posts: 530
Rep Power: 1
 
i installed the 4 individual coils from a 929.
it was hard to start, ran well momentarily, and stalled.
lots off gas smell from the exhaust. the spark is obviously weak.
i would really like to get this working right.
if anybody knows how or knows someone, that be cool.

drivit is offline  
post #5 of 8 Old 08-12-2007, 09:20 PM Thread Starter
Discen
 
jclong74's Avatar
 
Join Date: Aug 2006
Location: St Louis, MO
Posts: 264
Rep Power: 1
 

Awards Showcase
Veteran 
Total Awards: 1

Quote:
Originally Posted by drivit View Post
i installed the 4 individual coils from a 929.
it was hard to start, ran well momentarily, and stalled.
lots off gas smell from the exhaust. the spark is obviously weak.
i would really like to get this working right.
if anybody knows how or knows someone, that be cool.
I believe this is because the 919 uses a duel coil system. One is for cylinders 1&4 and the other is for 2&3. I a duel coil system the coil sends spark to both cylinders at the same time. This might be the cause of your problem

2006 919 (Sold)
2011 Cb1000r

"oh no there ain't no rest for the wicked, until we close our eyes for good." - Cage The Elephant
jclong74 is offline  
post #6 of 8 Old 08-13-2007, 04:24 PM
Old, Bold rider
 
robtharalson's Avatar
 
Join Date: Jan 2007
Location: Aurora, Colorado
Posts: 2,350
Rep Power: 1
 
Garage

Awards Showcase
Donation Veteran Community Leadership 
Total Awards: 3

Quote:
Originally Posted by drivit View Post
i installed the 4 individual coils from a 929.
it was hard to start, ran well momentarily, and stalled.
lots off gas smell from the exhaust. the spark is obviously weak.
i would really like to get this working right.
if anybody knows how or knows someone, that be cool.
Unless your control unit is specifically designed for individual coils (as the 929 obviously is) you will either overload the driver transistors in the control unit (coil primary windings connected in parallel), or provide only half the voltage the coils need (primaries in series). If the coils were connected in series the spark will be too weak to keep the fires lit for long and you may foul the plugs, but that will be the end of your problems. If connected in parallel, the ECU coil driver transistors may burn out in short order, and since they are encapsulated within the ECU it will be trashed (worst case scenario). Hopefully the driver circuit is current limited to prevent this, but I'm disinclined to short one of the coil leads on mine to test it.
Ideally, the igniter transistors in the ECU should be connected to external coil driver transistors (one for each coil) which can handle the load, but you will still have a waste spark.
My advice: remount the stock coils, ignoring the fact that they aren't trick, and ride the silly thing!

Rob

robtharalson is offline  
post #7 of 8 Old 08-13-2007, 05:14 PM
Cornicen
 
drivit's Avatar
 
Join Date: Apr 2006
Location: toronto
Posts: 530
Rep Power: 1
 
thanks for the helpful details, no damage, i'm riding it.
gonna hunt down a 929 ECU this winter.
try and swap out just the ignition side.
with a hacksaw....................

drivit is offline  
post #8 of 8 Old 09-10-2007, 01:34 PM
Tribuni Angusticlavii
 
Join Date: Nov 2006
Location: NJ
Posts: 3,704
Rep Power: 1
 

Awards Showcase
Trackday Recognition Donation 
Total Awards: 2

If you crank up the boost high enough on the gpz, you'll eventually blow out the spark.
We use a pair of Dyna's configured similarly to the stockers (direct swap) but stronger. If you really had the need for more spark that would probably the way to go.

gpzTurbo is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Wrist Twisters forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

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 Off
Pingbacks are Off
Refbacks are Off

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