Topic: 74 CB550 -no power

[Kenzo1979]

OK, a little more information that helps paint a picture. So the bike had power with the same exact type of battery. The battery has a decent charge on it. At this point I would say that you just need to make sure your battery is connected properly. If the only thing you did was take the old battery out and put a new battery in, and you had power when you left the keyswitch on, it would seem likely that you should have power now. Again, use the voltmeter and follow the 12 VDC. At this point you’re just going to have to use all the info that everybody posted and trace your electric. We could type new posts all day but until you do that,  you’re not gonna get anywhere. It’s either that or have somebody physically come over and do it. Do you have any friends that ride and take care of their own bikes? Do you know anybody who is handy with electronics or an electrician?   Not trying to be rude but the course of action has been laid out for you.  This isn’t even about getting the bike started at this point, from what you’re suggesting, you don’t even have power. That battery is delivering power to the initial points of the system. Trace the path.


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[Stev-o]

If i find that a fuse has blown, i would imagine this would happen again if the underlying issue isn't addressed. correct?

Yes. Do a visual inspection of all the wiring, look for damage to the insulation where the wiring may be grounding out, also check for bad connections and corrosion.  Good luck

[goodtryer]

Try the kickstart, with a spark plug removed & grounded to the engine, key on, kill switch set to run. Do you get spark?

[RAFster122s]

Kill switch will sometimes cause issues on a bike with inconsistent behavior causing no start. Disassemble the switch after slipping a large clear plastic bag over the switch... One large enough to work inside. If anything goes flying the bag catches it. The tiny ballbearing in the switch often likes to go mia when disassembling also...

[bustech51]

Like I  said a few messages ago and is being repeated by kenzo1979 GET A SCHEMATIC, A DMM as well as a small pick to help open up the various connectors and if necessary remove the wire, a small wire brush and fine sand paper.  Get all these things together and a bunch of time.  Trace the fault (there may just be more that 1 bad connection), remove, clean, reconnect and repeat. 

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[Honigsl]

Ok, so i have the schematic ...please bear with me, i am new at this but really want to figure this out for myself. I've used the multimeter on the battery and we are good on voltage.  I removed all 3 amps and checked for continuity and they all read close to 00.0. so the fuses are good.

turning the multimeter back to 20 DCV, I next checked the fuse relay box by connecting the negative wire on the multimeter to the negative terminal on the battery and touched the red wire to the fuse relay (key not in ignition). doing this gave me 00.0 of voltage running through the fuse relay...does that sound right or should i have had the key in the ignition?
i have attached pics of the fuse relay box in case it helps ...

[newday777]

yes, the PO rode the bike out to meet me...I checked the voltage on the current battery last night and read 12.4 V, so the battery isn't the issue. It's either the connections to the battery (because the F1 terminals are the worst) or a short in the circuit. If i find that a fuse has blown, i would imagine this would happen again if the underlying issue isn't addressed. correct?

Have you load tested the battery?

[Little_Phil]

I accidently left the ignition switch on when I took the key out and the battery died.

Only just reading this and scanned replies so apologies if already noted. Key can only be removed in off position which kills all circuits, including ignition, or P position in which case just rear light (in US).

[RAFster122s]

Aftermarket switch or badly worn original switch might let the key be removed, but as was said, should only be able to be removed with ignition switch turned to off or park positions.

[Honigsl]

OK, a little more information that helps paint a picture. So the bike had power with the same exact type of battery. The battery has a decent charge on it. At this point I would say that you just need to make sure your battery is connected properly. If the only thing you did was take the old battery out and put a new battery in, and you had power when you left the keyswitch on, it would seem likely that you should have power now. Again, use the voltmeter and follow the 12 VDC. At this point you’re just going to have to use all the info that everybody posted and trace your electric. We could type new posts all day but until you do that,  you’re not gonna get anywhere. It’s either that or have somebody physically come over and do it. Do you have any friends that ride and take care of their own bikes? Do you know anybody who is handy with electronics or an electrician?   Not trying to be rude but the course of action has been laid out for you.  This isn’t even about getting the bike started at this point, from what you’re suggesting, you don’t even have power. That battery is delivering power to the initial points of the system. Trace the path.


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Ok, so i tested with a DMM  at the first point and had a DCV reading of a little over 12 V. Next, I tested the fuse relay and the fuse with the arrow is the only one that had a reading of over 12 v. The other 2 fuses had no reading at all.  Is that good or bad?

[Kenzo1979]

Yeah that’s your main fuse. Should be a 15 amp fuse, when you turn the key in the ignition, the other two fuses should also get 12 V.  Again follow that wiring diagram that I included in one of the posts. And you can follow the path of the voltage.


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[bustech51]

I know that when I started working on my bikes the schematics were confusing.  To many lines and colours. 
What i did was take pencil to paper and draw out the circuit that needs to be worked out.  Make it simple and less confusing.
I also blew up the schematic to be 2 pages and then had them laminated in 1 sheet  so they stay clean organized and easier to read because of their size.

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[Honigsl]

Yeah that’s your main fuse. Should be a 15 amp fuse, when you turn the key in the ignition, the other two fuses should also get 12 V.  Again follow that wiring diagram that I included in one of the posts. And you can follow the path of the voltage.


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Ok, turned the ignition key 1 click and checked the battery voltage. It went to down to 11.3 v. Then checked the main fuse, and that went down to 10.5 v. There was no voltage for the remaining 2 fuses...
even with the the voltage dropping, i should still have some sort of power to headlight, correct?

[RAFster122s]

Well, you need to pull the ground terminal off the battery and then pull your fuses and clean the fuse box and fuses with a brass brush. There is visible corrosion on the fuse and fuse terminals in your photo.

Then clean the negative connection you pulled and then reassemble it.

Check your voltage on the red and black wires at the ignition switch.
The drop to 11.3v is an issue...lets figure out why you have that much drop.

[TwoTired]

The drop to 11.3v is an issue...lets figure out why you have that much drop.

If you are drawing more than 7 A out of a 7AH battery, it's going to drop voltage commensurate with the load applied.

Further, the battery should have 12.6 v after resting an hour after a charge.

An unloaded battery reading of 12.4 is only 75% charged.  And an unloaded battery at 11.4 is beyond fully discharged.  Probably going to need an off bike charger.  Consider using a car battery to provide power for long probing investigations.

I recommend you disconnect the headlight while you are troubleshooting.  That will eliminate a 3-5 amp load (depending on wattage).  That's easy with the stock bike by just removing the headlight fuse.  But, it seems certain that the bike builder didn't bother providing a schematic of his changes before making his profit.

The stock bike draws about 10 Amps with key switch and lighting on.  Which is likely why the stock battery is 12 AH and can provide about 200 cold cranking amps for the e start.  That 7AH battery is mostly for computer back up purposes and spends most of its normal life on float charge, only draining for power outages and allowing the computer to perform back ups and saving Data in progress before shutting down.  It's a silly choice for an SOHC4 that doesn't provide enough alternator power at idle to keep a battery charged.

Good luck!

[bryanj]

TT just emhasised what i said in that the battery you have is no good for running the bike you have

[Kenzo1979]

TT just emhasised what i said in that the battery you have is no good for running the bike you have

C’mon.  It’s good enough to get it over to the person you sell it too.

J/k!!!  You’ll get it going.  Listen to the people here.  Take the advice.  Probably going to want to get a beefier battery.  Something with lug terminals too. Who knows, you may want to undo many things that were altered to make the bike “cooler.”


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[RAFster122s]

The batter holder on the swing arm without any vibration dampening is going to punish your battery too. Time to pull out the grinder after pulling the swing arm and grind that holder off the swingarm.

[bryanj]

"Batter the swing arm" Huh?

[RAFster122s]

"Batter the swing arm" Huh?

Haha, battery mounted on swing arm...

[bryanj]

Hadnt noticed that, never a good idea imo

[Scott S]

This is the cover you want to look under for the starter motor BTW



 And you do know that the choke is ON in that pic, right? You're new to this bike and to the 550, and that's a common mistake.


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