Startup!!


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CBX1000FAN
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Startup!!

Post by CBX1000FAN »

I have a interesting situation and maybe someone can shed light??

I cold start my CBX (1979) without an issue. It has a new battery with even better specs than OEM - I bought it two months ago because I wanted to eliminate a battery issue (old battery did the same as described below!). Once warmed up I'd ride a few km and then return home. After switching off and turning the tank tap off I usually wait for a minute or so and then start up again (like one would do at a filling station for fuel or air)... however the bike then seems to have much more compression (or something??) as the battery struggles to start the bike. After about 5 minutes it just starts up normally again. I checked the voltage during cold start: I indicates 12.8V and drops off to about 12V during startup. However when hot (about minute after switch off) the battery indicates 12.8V but now during startup falls to 9.8V.... As I mentioned the "old" OEM 18A/H battery did the same.

The starter seems just fine and the battery is charged while the motor is running - The volt meter indicates about 13.5V.

Your guess / comment??

Regards!

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NobleHops
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Re: Startup!!

Post by NobleHops »

This sounds like a starter problem to me. Has it ever been serviced?
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

CBX1000FAN
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Re: Startup!!

Post by CBX1000FAN »

The starter was removed and inspected... I could not see issues there... After all it never has an issue apart from hot start up.... Regards!

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NobleHops
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Re: Startup!!

Post by NobleHops »

The voltage drop indicates either a faulty battery or high resistance in the starter/circuit, including the grounds. The easy one to check is the current path to the starter. Start with shorting the solenoid with a screwdriver when it's hot, and if it repeats the problem, then it isn't the solenoid. Check resistance on the starter hot lead. Check the ground. Check the starter lead terminals, are they clean and tight? Remove the starter, skin it, and verify that the brush plate is making good solid contact with the starter body via the little ears on its edge, as that's how it grounds. Some electrical connection in your starter circuit is becoming weak/poor as a result of things heating up and spreading apart.
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

CBX1000FAN
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Re: Startup!!

Post by CBX1000FAN »

Thanks! Will check asap.

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