Author Topic: Can I use 650 coils on a 550?  (Read 1055 times)

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Offline mono

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Can I use 650 coils on a 550?
« on: June 26, 2013, 04:07:08 PM »
Yes, no?   Pretty sure I've got a dead/dying coil on the 550. :(

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Offline ckreb

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Re: Can I use 650 coils on a 550?
« Reply #1 on: June 26, 2013, 04:29:47 PM »
Depends on the vintage of both bikes. Grab a multi-meter and check the ohms. If they're the same you're golden.

Offline Tews19

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Re: Can I use 650 coils on a 550?
« Reply #2 on: June 26, 2013, 04:34:29 PM »
I have a nice set for sale. Pm if you are interested
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Offline mono

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Re: Can I use 650 coils on a 550?
« Reply #3 on: June 26, 2013, 05:39:51 PM »
Thanks ckreb, I'll do that.   Just the resistance is important?

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Offline Bootlegger56

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Re: Can I use 650 coils on a 550?
« Reply #4 on: June 26, 2013, 08:27:33 PM »
If my feeble mind serves me correctly the 650 coils are @ 2.2~2.4 ohms.  I think I had this conversation with Hondaman when I got my last transistorized ignition system from him.  If I remember correctly he commented that with the limited power resources available from the 550 charging system that the 650 coils put too much of a load on the system even with his resistor pack installed.  Again I am working from memory and maybe someone else can verify this.
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Offline ckreb

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Re: Can I use 650 coils on a 550?
« Reply #5 on: June 26, 2013, 10:22:54 PM »
Duh wasn't thinking. 650 came with EI. And put out around 10k more volts. So no they will not sorry.

Offline Deltarider

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Re: Can I use 650 coils on a 550?
« Reply #6 on: June 27, 2013, 12:23:46 AM »
The CB650 has a CDI ignition, so no.
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Offline dave500

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Re: Can I use 650 coils on a 550?
« Reply #7 on: June 27, 2013, 02:39:00 AM »
its not an actual cdi type ignition but thats a common name for any of the factory electronic types.

Offline mono

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Re: Can I use 650 coils on a 550?
« Reply #8 on: June 27, 2013, 07:25:08 AM »
OK thanks guys!  it was worth a shot, as i have a 650 with no keys just laying around my garage lol.  well, it's on the kickstand, but you get it.

Offline mono

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Re: Can I use 650 coils on a 550?
« Reply #9 on: June 29, 2013, 01:07:31 PM »
Good news- found the problem isn't in the coil.  The female bullet connector for the ground wire on my 2-3 coil is broken!  Didn't even notice till probably the 3rd time I looked at it.  The female connector was cracked and kind of "hinging", so it was getting a good connection some of the time.   Cheap fix, but I don't have any connectors on hand :(

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Offline Bootlegger56

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Re: Can I use 650 coils on a 550?
« Reply #10 on: June 29, 2013, 02:54:53 PM »
That sure beats having to get a replacement set of coils or coil.  I usually don't get that lucky and by the time I find my power issues they have that "electrical death smell" if you know what I mean.
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