Topic: Cb550 has no spark. Help please

[Jimsun]

Hello guys. My bike was running fine last night and today the bike did not want to start at all. Heres some info and stuff ive done

1. 3k tune up done less than 1,000 miles
2. There is spark at the plugs
3. With kill switch on, there is no sparks at the plugs
4. There more than a half tank of gas
5. There is gas in the plugs. Its wet
6. I tried using a starter spray
7. I tried to crank with varying throttle
8. I tried bump starting it. It didnt budge too like it felt like it the ks was on

[MoMo]

Three things a motorcycle needs to run:  good compression, spark at the right time and fuel in the correct mixture.  eliminate one by one.  Are the plugs black?

[Jimsun]

Hi and thank you for the reply.

I rebuilt the engine last year and the compression is about 120 across all four.

I have overhauled my carbs  at the start of this season and its been running great. Everything is stock. Pipes. Airbox.

Spark plugs are wet.
Plugs are black because it was idling before i turned it off last night (if rpm is over 3-4k the plugs are bronze). I placed a new set and theyre just wet.

[MoMo]

Hi and thank you for the reply.

I rebuilt the engine last year and the compression is about 120 across all four.

I have overhauled my carbs  at the start of this season and its been running great. Everything is stock. Pipes. Airbox.

Spark plugs are wet.
Plugs are black because it was idling before i turned it off last night (if rpm is over 3-4k the plugs are bronze). I placed a new set and theyre just wet.

If you have gas and spark , I'd check compression.  Try turning the petcock off, drain the carbs, petcock back on and see what happens

[Jimsun]

Hi and thank you for the reply.

I rebuilt the engine last year and the compression is about 120 across all four.

I have overhauled my carbs  at the start of this season and its been running great. Everything is stock. Pipes. Airbox.

Spark plugs are wet.
Plugs are black because it was idling before i turned it off last night (if rpm is over 3-4k the plugs are bronze). I placed a new set and theyre just wet.

If you have gas and spark , I'd check compression.  Try turning the petcock off, drain the carbs, petcock back on and see what happens

My compression is great all 125-130 across.

Dumped the fuel off the bowl. Didnt work

[harisuluv]

Just because you can see spark, doesn't mean that you have GOOD spark or that your plugs aren't fouled/too wet. 

I doubt you lost compression across the board and since you tried starting fluid, my guess is your plugs are bad/fouled.  Try new plugs, once they are fouled they are done.

[Jimsun]

Just because you can see spark, doesn't mean that you have GOOD spark or that your plugs aren't fouled/too wet. 

I doubt you lost compression across the board and since you tried starting fluid, my guess is your plugs are bad/fouled.  Try new plugs, once they are fouled they are done.

Thanks for the reply. It WAS good spark yesterday blueish colour. This morning was blueish- orange now theres no spark. I have a feeling the no spark is connected to the kill switch as i have opened it. I have replaced the plugs and gaps are to spec

What else would cause a no spark at the plugs?

I rechecked compression again and theyre around 140-150 across with WOT and using the starter to crank the engine.

Voltage is steady as i have a 12v car battery connected in parallel with my 12v motorcycle battery.

I havent ridden it in the rain at all. Connections are pretty solid green.

[harisuluv]

So what changed?  You opened up the kill switch and messed with it, fix it and try again.

[Jimsun]

So what changed?  You opened up the kill switch and messed with it, fix it and try again.

I opened it up to check and see if its operating. With continuity test and the wires unplugged on both ends, it should beep when its in the right position

[harisuluv]

I thought you said before it has spark when it should with the kill switch on/off?

[Jimsun]

I thought you said before it has spark when it should with the kill switch on/off?

Yes but when i bumped started it the response i got was as if there the ks was engaged. So i double checked if its working correctly.

If you don't have spark with the KILL set to RUN! Check the BLK/WHT wire from the RH switch to the coils. It should have 12v in this position. Use a meter, and probe the connection point at the coils, where the BLK/WHT wires exit the bars and connect to the harness, and by switching from KILL to RUN.

Are all other electrical functions working?

Thanks i will recheck. Maybe i unplugged and created a bypass.

[Gene]

I just replaced my kill/run switch which, as it turns out, was exactly the problem. I had the same thing - ran fine the night before, next day no spark at all.

http://forums.sohc4.net/index.php/topic,150294.msg1714966.html#msg1714966

[Jimsun]

Thanks gene. I have replaced my kill switch and its still not giving me spark.

I have replaced the condensers as per manual advise but no cigar

[Restoration Fan]

Do the 550's have the kickstand switch?  Also, is it possible the clutch switch has gone bad?

[Jimsun]

Do the 550's have the kickstand switch?  Also, is it possible the clutch switch has gone bad?

Thanks i dont think so. I have gone and even do a bypass and still nothing.

[MoMo]

I thought you said before it has spark when it should with the kill switch on/off?

Yes but when i bumped started it the response i got was as if there the ks was engaged. So i double checked if its working correctly.

If you don't have spark with the KILL set to RUN! Check the BLK/WHT wire from the RH switch to the coils. It should have 12v in this position. Use a meter, and probe the connection point at the coils, where the BLK/WHT wires exit the bars and connect to the harness, and by switching from KILL to RUN.

Are all other electrical functions working?

Thanks i will recheck. Maybe i unplugged and created a bypass.

have you done this??? ...Larry

[Jimsun]

I thought you said before it has spark when it should with the kill switch on/off?

Yes but when i bumped started it the response i got was as if there the ks was engaged. So i double checked if its working correctly.

If you don't have spark with the KILL set to RUN! Check the BLK/WHT wire from the RH switch to the coils. It should have 12v in this position. Use a meter, and probe the connection point at the coils, where the BLK/WHT wires exit the bars and connect to the harness, and by switching from KILL to RUN.

Are all other electrical functions working?

Thanks i will recheck. Maybe i unplugged and created a bypass.

have you done this??? ...Larry

which part are you referring to?

[MoMo]

I thought you said before it has spark when it should with the kill switch on/off?

Yes but when i bumped started it the response i got was as if there the ks was engaged. So i double checked if its working correctly.

If you don't have spark with the KILL set to RUN! Check the BLK/WHT wire from the RH switch to the coils. It should have 12v in this position. Use a meter, and probe the connection point at the coils, where the BLK/WHT wires exit the bars and connect to the harness, and by switching from KILL to RUN.

Are all other electrical functions working?

Thanks i will recheck. Maybe i unplugged and created a bypass.

have you done this??? ...Larry

which part are you referring to?

checking for  12 v at the black/white wires to the coils...Larry

[Jimsun]

I thought you said before it has spark when it should with the kill switch on/off?

Yes but when i bumped started it the response i got was as if there the ks was engaged. So i double checked if its working correctly.

If you don't have spark with the KILL set to RUN! Check the BLK/WHT wire from the RH switch to the coils. It should have 12v in this position. Use a meter, and probe the connection point at the coils, where the BLK/WHT wires exit the bars and connect to the harness, and by switching from KILL to RUN.

Are all other electrical functions working?

Thanks i will recheck. Maybe i unplugged and created a bypass.

have you done this??? ...Larry

which part are you referring to?

checking for  12 v at the black/white wires to the coils...Larry

Yes i have. So i figured out the problem. I had her running after changing numerous parts and when shes running, i decided to slowly put together all my old parts back to find out the real cause. it turned out being both my coils 1/4 2/3 are not firing.. which is extremely odd for both to go bad

[MoMo]

Both coils going bad is something I've never seen in 40 or so years...Larry

[Vinhead1957]

More likely the feed from the kill switch

[Stev-o]

Both coils going bad is something I've never seen in 40 or so years...Larry

And I would place a wager against it. How much do you want to lose?

[MoMo]

Both coils going bad is something I've never seen in 40 or so years...Larry

And I would place a wager against it. How much do you want to lose?

I'd put up a million space bucks against it....Larry

[MoMo]

I'm in for $250,000 (why be greedy at someones naivety?)

You're a better man than me cal

[Jimsun]

Its not the kill switch. Ive done many types of bypass and tests and i'm an electrician by profession.

I do have power on both coils have power feeding them.