1964 CA77 - dies at low rpm when headlight on!

ericmanuel · Post by **ericmanuel** » Wed Aug 31, 2016 8:14 pm

This has me a little puzzled. Dies at red light when headlight on. turn headlight on it starts first kick. Battery showing 12 volts when checked. Also will not start using electric start, seems like not enough juice.

Could this be my rectifier? Is there a way to test the rectifier?

Thanks min advance for your help.

Eric Manuel

ericmanuel · Post by **ericmanuel** » Wed Aug 31, 2016 9:21 pm

Used the following link to test the rectifier/regulator http://www.oregonmotorcycleparts.com/FAQ.html

According to this my rectifier/regulator is working... If I did it correctly.

Really stumped now. Maybe my rectifier/regulator is functioning properly now and later when it is hot and under load it is failing. May be worth $30 to find out.

Any thoughts would be helpful.

Eric Manuel

rrietman · Post by **rrietman** » Wed Aug 31, 2016 10:45 pm

first off, if your battery reads 12v, thats a discharged battery. how old is it? they seldom last two or three years. should be about 12.6-8v. at just 12v I would be surprised if it would start with the electric start. might start with kicking. you don't have a rectifier/regulator---just a rectifier, the battery is the regulator. charge your battery off the bike. give it a couple hours. if it still reads 12.6v, I'll bet you will start up just fine . if not you have a failed battery. if it does start and then after running just reads 12v (or so), you have a failed charging system. CLEAN ALL CONNECTIONS then you need to start changing parts, rectifier is the first thing. hope you don't need to go any further.
Good luck
Randy

ericmanuel · Post by **ericmanuel** » Fri Sep 02, 2016 11:00 pm

Update::

Replaced rectifier with one from Radio Shack. Here is the link to the one I got https://www.radioshack.com/products/50v ... 5717581317. Easy fix but battery still not holding a charge. Cost me 5 bucks to determine my battery was bad. ( I suspected as much)

Replaced battery today and rode at night with headlight on for about an hour with no problems.

Thanks for your help.

Eric Manuel

Nick · Post by **Nick** » Thu Sep 22, 2016 7:41 pm

Back when I was working as a bike mechanic (a long time ago, and not on Hondas) the local Honda distributor said that something like 90% of all electrical system warranty claims were the result of bad batteries.