Honda 1975 Honda CB500T DOHC won't hold charge.

Next Topic
 
classic Classic list List threaded Threaded
4 messages Options
Reply | Threaded
Open this post in threaded view
|

Honda 1975 Honda CB500T DOHC won't hold charge.

BrandonMurphy826
So i'm new to this forum and am seeking help/advise with my bike. I have a 1975 CB500t. it wouldn't idle when i got it so i rebuilt the carbs and it idles perfectly. I've even rode it around my street a good few times. Where the problem comes in is when you shut it off and then try to start it again.
It will randomly not start (turns over extremely slow as if the battery is dead). sometimes this happens if i stall out the bike. other times i'll park, go inside for water, come back out to ride it around again and it won't start(turning over extremely slow.) i have looked under the seat at the starter and no wires are exposed. Also i just bought a new maintence free battery for the bike. If anyone can just point me in the right direction it would be much appreciated. I have an original service manual to reference but there's a lot of things to check. so i'm trying to get more opinions before i go checking everything.
Reply | Threaded
Open this post in threaded view
|

Re: Honda 1975 Honda CB500T DOHC won't hold charge.

TOOLS1
Administrator
I would start with cleaning all the battery cable connections. Then I would check the charging system. After that would be the starter, especially if this is only happening after the engine gets hot.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
Reply | Threaded
Open this post in threaded view
|

Re: Honda 1975 Honda CB500T DOHC won't hold charge.

bohemiafens
In reply to this post by BrandonMurphy826
So the battery is new and off the correct amps, when it fails to start, try putting the battery on charge, to see if it is fully charged.
Reply | Threaded
Open this post in threaded view
|

Re: Honda 1975 Honda CB500T DOHC won't hold charge.

Re-run
Administrator
In reply to this post by BrandonMurphy826
I got a "brand new" battery once, had a short inside that read 12.6 volts on a meter but the second a load was placed on it, nothing. As Tools said, clean the battery connections, but also clean the connectors between the stator  and regulator/rectifier. Then, start the bike, hook up a meter and rev the bike to at least 2000 rpm, better to be at 2500 rpm. Your voltage should be 13-14 volts. If it is not, then if you have to stock regulator, try to adjust it and see if that helps.

Also, when you ride, keep in mind these bikes charge just about nothing below 2000 rpm, just the way they were made. Many of them also put out very few amps for charging, so short rides will really drain things. You should clean ALL connections, or replace them with new hardware. Changing to led bulbs can also help reduce load which helps with charging.

Anyways, if the charging checks out, then as Tools said, it could be the starter being hot and turning slowly.
Does the bike start fine with the kicker?
The ride IS the adventure. The destination is just to get gas!