Typical Voltage drop while cranking

[greimers]

I am discovering the quirks of my newly acquired '85. I recently experience the slow crank when hot.

I suspect the battery but will also check the crimp.
My levels are:
Ignition off - 12.4v
Ignition on - 11.6
Cranking - 9.5

I suspect 9.5 is too low as is 11.6 with the key on. I'll probably replace with an Odyssey and check the factory crimp.

What is the typical drop in voltage while cranking?

 

[sdt354]

I think it's battery time too. 10.6 for a few seconds is about minimum.

 

[davesax36]

I thought the pick-ups would tell the cdi to give up if the battery was below 10v? I'm gonna check mine when I get home in two weeks.

 

[jfeagins]

Like SDT says, anything below about 10.6V should be the minimum. Anything less, and the CDI box will not operate as desired. That is why so often, a bike will want to finally hit on a cylinder exactly as the start button is released. At that moment, the voltage goes back up while the motor is still not done spinning from the starter try.

 

[wildweasel_pt]

Battery is dead. It should read about 12.9v on rest

 

[Erikvb]

+10 dead battery. But do a bit more than just putting a gel battery in, there's an excellent write-up in the how-to section:

- crimp fix (but I would just wire directly r/r to battery with better gauge)
- r/r itself since you have an 85
- get your multimeter out and get a feel for where the power is going, I learned a lot from that.

Quick-fix before getting the new battery; pop the breaker on your headlight. It is better than walking home. If your charging is iffy, the headlamp sucks your battery empty. Without 55W of headlight you will be fine, no matter.

 

[greimers]

I plan on starting on this list tonight. What wire gauge is recommended for the R/R?

 

[sdt354]

I plan on starting on this list tonight. What wire gauge is recommended for the R/R?

12 ga. should do it.

 

[DMAN999]

Here's a link to the guide:
http://www.vmaxforum.net/showthread.php?t=19108

He used 14 ga. in the guide, so 12 ga. will work fine as well.
I believe I used 12 ga. when I did mine but I really can't remember because it been a few years.

 

[Redbone]

I used 12ga for updating my 92 R/R to a 04 Ranger R/R.

 

[greimers]

Soldered the crimp. Got an increase of .5v to 13.6 at idle. It's interesting to see such a difference just by soldering a connection. Still not high enough though so I'll be going ahead with the rectifier upgrade.

 

[jfeagins]

13.6V @ idle is great.

 

[jagco1]

Check your stator wiring to, volts across each leg should be the same.
mind had brake fluid that spilled from the clutch bleeding and made my stator short when riding


the bracket a made - the r/r mounts to it and go's behind the lift side cover and hangs on the bike rail and the side cover holds in place.

I have not mounted it there yet- I just tried to make sure it will fit. My volts at idle 14.57

I just seen your last post - I was looking for pictures on this computer.