Hello.

I picked up a 1990 CBR 600 last week for real cheap because the motor would not run. After I got it back to my house I diagnosed it as having no spark on all four cylinders. I downloaded a manual for it and ran through the checklist of electrical tests to pin point the problem. All switches are working fine, all wiring to the CDI is good, the pulse generator resistance is in spec, and the resistance at the coils is in spec. This seems to leave the CDI box as the only item left that could be the cause of the problem.

I have not been able to find any way to test the CDI box to make sure that is the problem before I buy another one. Is there a way to check it? like resistance between specific pins or continuity when power is switched on? If I do have to replace it, are there any other years of CBR's that have compatible CDI boxes? Finding another box from a 1990 may be possible, but I would rather have a wider range of years to search for.

Thanks in advance for any help.

-Price

 

I read the post and wanted to know if you checked all of these...
1.30A main fuse
2. ignition switch
3. 10A sub fuse
4. engine kill switch
5. side stand switch
6. neutral switch
7. main ground points in general
8. connectors for all of the above
You may be able to use a CDI from an '89 but not '87 or '88.
On the 6 pin CDI connector measure voltage with the key on and engine kill switch in run. Measure between the black/white and green and then the blue/yellow and green. You should get battery voltage. If you get battery voltage, check pulse generator resistance ( which you did ) = bad CDI. If you do NOT get battery voltage then start rechecking items 1 - 8.
CDI problems, from my limited forum knowledge, are uncommon. I would suspect something else first.

 

I checked all of the above mentioned and everything was checked out fine, no fises blown and all switches function as they should. I also checked both coils using some spare wire and a battery and both of them spark. It would appear that everything before the CDI box and after is working as it should.

Will a CDI box from a later year CBR work? say an F2 or F3? They look similar if not identical from the outside and appear to have the same 16 pin connector as mine does. Is there a fundamental difference in the control sensors in the later year bikes?

Thanks for the response Billistic

 

As far as I know, only a 1990 CDI box will work as a direct swap. If you do a search you will find others that have tried putting a 1990 motor into 1989 frames (and vice versa) and can explain what works/doesn't work.

Make sure that the battery you are using is fully charged.

KongBastard