1987 nc23 no spark

[Savagealmond]

Hi all
I have an nc23 was running lumpy so I stripped carbs and rebuilt them hoping that it would run fine...
After i rebuilt them fitted them fuel ect no spark I've tried new plugs spare set of coils I know to be working no spark
The fuel pump works but only if I power it up with a power probe it does not prime when I switch the ignition on (if it's supposed to) I've got a car battery on a set of jump leads with bike battery removed. Kill switch is working correctly.
Power to the coils and getting a pulse.
I've checked the fuel pump relay but not sure if it's working do they click? Does the fuel pump relay have something todo with the spark? I really don't know much about Hondas more of a Suzuki man myself bought it off a mate as a non runner manged to get it running but now it's no good really need help with it!!

[gullarm]

As the only parts you removed are the coils, plugs and carbs I would suggest you wired the coils back up wrong! Or possibly one of the connectors has broke, internal wire fault, check continuity from end to the other, check the wires you have removed.

Fuel pump is irrelevant, as long as there is fuel in the carbs ( which there wont be as you have rebuilt them ) it will fire up. Gravity feed fuel into the carbs, ensure the float bowls are full of fuel.

If you get a pulse to the coils they should spark the plugs, you have 4 plugs and 2 coils to work from so at least one set of coils should work.

[Savagealmond]

I've wired them back correctly I'm sure I've checked all connections would the cdi regulator be anything todo with it? Tried removing the connector and it seems to be stuck could be melted I don't know.

What your saying about the fuel pump is that it only works with the engine running or turning over on the starter? Because if so its not happening

Is there any wiring under the carbs that I could have knocked? Was about a year ago I stripped and rebuilt them

I know there's not much to these bikes
Cheers

[dunkenb]

Have you checked the fuse on the starter relay? Could be a dodgy ignition lead? Id also use the correct battery.

[Savagealmond]

i have put a good battery on it no joy by passed the kill switch no spark! really starting to come to a loose end gonna check the loom for breaks in the wires but thats the only thing it could be!

there is one thing that it could be... the plug on the rectifier regulator has melted not 100% sure it works either could a faulty reg cause a sparking issue?

[jamishs14]

Hey dude I had exactly the same problem with a 1988 cbr400rrj and it was as cdi fault. From what I have found on the net its quite a common fault for the nc23's and the best fix is replacement. I have replaced with a hong kong version but it only lasted 3 starts and died. My recomendation would be either a genuine honda cdi or an hrc ignitech cdi from www.gfracinguk.com . Good luck and I hope you get it sorted.

[Savagealmond]

beginning to think it was cdi but no way of telling! i do know a place that can fix them gonna see how much it will cost!

[tr8theshape]

It might be worth checking the connectors to the cdi first.

I found that the red connector was quite loose and the bike would only fire when the cdi and connector were in a certain position relative to each other therefore making the connection.

The bike would turn over like a good in but showed no sign of firing at all. It was easily fixed by taking the pins out of the connector, cleaning them a squeezing the terminals closed slightly.

Probably not the case with yours if you haven't been in that area but a quick easy and cheap thing to check.

[Savagealmond]

from what i can remember the bike was charging at 16 volts which could cause the cdi to fry

spoke to a mate of mine ex honda mechanic he said i could be buggered

[dunkenb]

Are any of the windings on the alternator/stator burnt? Honda reg/recs are notorious for failing ,use one from a different model that has a finned heat sink on it ( cbr900) . Check the wiring from and to the reg/rec too.