Honda Rebel Forum - Reply to Topic
Thread: Ignition problem. One spark ! Reply to Thread
Post Icons
You may choose an icon for your message from the following list:

Register Now

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

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


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

Email Address:


  Additional Options
Miscellaneous Options

  Topic Review (Newest First)
02-16-2020 06:17 PM
miyami While this shows that there are differences in the CDIs, it also shows that all of them are not functioning, since I do not get the 100V minimum peak at the ignition coil. And to be sure for these tests, I disconnected all b/w (nanny wires) in the handle bar to guarantee the run/stop switch and the ignition switch are not at fault, and also grounded the green/white wire to exclude the side stand switch from being the culprit.

With this, I went through all the trouble shouting items in the rebel 250 official repair manual (page 16-3), and it points to a faulty CDI.

This leaves me puzzled. Unless all 3 CDIs are toast, or there is a special version needed for this bike, it stops making sense to me.

I am almost at the end of my wisdom and am thinking of bringing the bike to a Honda shop this week, unless somebody has some last advice.
02-16-2020 06:07 PM
miyami My original CDI - image 2: input from the exciter coil; image 1: output to the ignition coil
02-16-2020 06:06 PM
miyami With installed CDI I get this:
Red CDI (Argentinian, from Rick's motorcycle electric) - image 1: input from the exciter coil; image 2: output to the ignition coil
Chinese? CDI (cheap from ebay) - image 3: input from the exciter coil; image 4: output to the ignition coil
02-16-2020 06:01 PM
miyami Some more tests:
I did verify all connections in the harness. Everything looks good and is connected as it should. No groundings or open connections as far as I can see.

- I did pull the stator and it looks nice and clean (image 1). Not bad for a 29000 mile bike.

- I took a strong magnet and moved it in front of both exciter windings individually, and could see responses in the oscilloscope, so I assume the exciter coil is ok.
- I did some more measurements of the exciter coil and pulse coil after putting everything back together and it looks in spec (exciter coil: image 2 and 3, pulse coil: image 3; all with CDI not connected.
- Then I had a closer look again at the 3 CDI boxes I have. I installed the CDI one after the other and got some kind of weird readings.
02-14-2020 07:20 PM
miyami Sorry, SoakedKarma. I just saw your post right after posting my previous one....
02-14-2020 07:18 PM
Originally Posted by bweighmaster View Post
Remove every component , clean all grounding contacts ... re install , run and check .... grounding of cdi , coil , stator , and pickup coil is most important ....

The wiring harness only shows one grounding point (top middle) that attaches to the Rectifier mount. Is this the only point where a cable is attached to the frame (ground) ? SoakedKarma's ignition system wiring has 2 Ground points.

Originally Posted by SoakedKarma View Post
The wiring diagram at end of manual is for 85-87 1st generation Rebel and doesn't apply to your year bike..

One for the ignition coils, and one for the CDI - or is this just the diagram ?
02-13-2020 10:01 AM
SoakedKarma Green harness ground has 1 connection point, bolted to frame above and aft of spark plug coils..
02-12-2020 11:41 PM
miyami Are there any particular grounding points to look for other than the green wire at the CDI and at the ignition coils primary side ? I thought the rest is all grounded through chassis attachment screws (e.g. stator, spark plugs, etc.)?
02-11-2020 03:29 PM
bweighmaster Remove every component , clean all grounding contacts ... re install , run and check .... grounding of cdi , coil , stator , and pickup coil is most important ....
02-08-2020 09:01 PM
SoakedKarma danged if I know, anything is possible.
Very strange output signal though..
(GRN/WHT) = GND, BLK/WHT = open at CDI is correct in my book

below is a generic schematic of an AC Cdi to give you an idea what's inside
This thread has more than 10 replies. Click here to review the whole thread.

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

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