This is strange

[Auggie_1970]

So trying to go through the bike to eliminate why I'm haveing hot start issues. Battery is at 12.6 when bike is off. 13.71 @ 1,200 rpms, then 13.67 @ 4,000 rpms..

Did the crimp fix and got 13.89 @ 1,200 rpms, and 13.86 @4,000 rpm's.

Cleaned the ground on the frame and by the oil fill.. No change..

Then as I was syncing the carbs, I sill had the voltometer on the bike I noticed all of a sudden it drops to low 12's. What changed? This is odd. How can you go from 13.86 @ 4k to low 12's without doing anything.

Whats the possiblitiy that the regulator gets hot from the exhuast being so close to it that it overheats the regulator and messes things up. I'm going to have to do the electrical flow chart thing and hope to find this...Bike's a 2004 with 4800 miles..Would a bad battery cause something like this. Very strange

 

[spyder13]

I had a 86 vmax that had a bad stator. Would check ok until it was fully warmed up then it would short internaly

 

[mr.maxx]

how old is yure battery? the max NEEDS a strong one. a weak battery can cause issues. if its more than 2yrs old maybe yu can have it tested??

and double check to see that it has the correct amp rating.

a lot of max owners have hot start issues...in fact my o7 would crank hard when i 1st got it until the battery got fully charged.

also... a weak battery will put extra load on the regulator and make it hot.

start with a known good battery and work yure way thru.....u will get it sortedunk:

 

[Auggie_1970]

I would have to say that the battery could be suspect. Its a parts unlimited one. It died when I went to go buy the bike a few weeks ago. I pulled it and the fluid levels were really low. If I put a meter on it , I get about 12.4-12.5. When I hit the starter it seems to drop down to 9.90.
I hope its not the stator, thats expensive. I started to do the electricl flow chart thing and so far the stator ohms are .5-.6 on all three white wires. I'll try more tonight. If it was the battery would that cuase it to have good changing volts for the first 5-10 minutes then drop to low 12's..
Does anyone know how to make sense of that test for the regulator. I dont think my meter has a diode tester on it. Bit confusing

 

[naughtyG]

I would say your battery is on its way out. Change it ASAP - you can get a lot of much more expensive issues from running a weak battery.

I just got one of these
Panasonic LC-X1220P U-D5745 $ 47.95

from www.apexbattery.com

and I'm happy with it so far. Can't go wrong at $48 for a brand new battery.
I also bought a spare phone battery as over $50 shipping is free!

 

[Auggie_1970]

Thanks for the link. Cant tell from the picture but how are the terminals on the battery , same as stock? or do you have to route wires differently

 

[naughtyG]

the terminals are slightly different - vertical rather than horizontal. It comes with bolts nuts and washers though. I just bent the cable and connectors a little and they fit just fine.

 

[Auggie_1970]

Had a long day at work today , came home and ran out to the garage to do a few test. Thinking and hoping that all I need is a new battery. I did four test, not very consitant with checking at various rpms. But what I see is that the battery originally read 12.44 with nothing on. Then as the test progressed it increased a little each time. So it will be interesting t see how much it drops by tomorrow evening without charging it. Most importantly it really drops low when cranking it over..Lowest reading was on test 4 at 9.05V. I think from what I read if it goes that low, battery is shot or very weak...Can anyone confirm.. Also what kind of voltage drop do you guys see when you just turn the key on without starting it. Do my voltage drops seem the norm. What do you guys think about the state of my battery, time for a new one? Got a quote for and odessey for 115 shipped today from West Coast Battery. I'm going to do a little more reading about which is better between Yuasa, Panasonic, Odessey, etc.

The ? mark means I failed to observe the voltage at those readings.

 

[naughtyG]

check out this thread on batteries - plenty of info.

http://www.vmaxforum.net/showthread.php?t=7115&highlight=battery

Just don't spend too much time cranking with low power - it can do a lot of expensive damage to the starter clutch from what I've read.

 

[gamorg02]

check out this thread on batteries - plenty of info.

http://www.vmaxforum.net/showthread.php?t=7115&highlight=battery

Just don't spend too much time cranking with low power - it can do a lot of expensive damage to the starter clutch from what I've read.

yea +1 to that, i've heard that as well.....

i'll stick with OEM for what its worth.. my $0.02

 

[naughtyG]

I'll be sure to give a full report on the cheapo one I bought from Apex.

I know Uncle P's been running one of these for a while, and the acid test is coming right up - my bike will be parked from tomorrow until early July in the Florida heat.

We'll see how it cranks when I get home, and how long it lasts - I believe it came with a 2-year warranty, which is about all I expect a battery to last on average.

 

[Dan David]

The voltage on the battery usually drops when cranking the engine. However, the voltage should go up to at least 14+ volts at rpm over 3000. If it does not the rectifier/regulator is suspect. You could get a reading of 13 volts out of newly charge battery but it will not crank the motor because the amperage is well below what is needed to crank the motor. It is not voltage that cranks the starter, its the amperage.
Then again it could be your stator. Easy test. Start your motor, remove the + terminal from the battery. If the motor dies, your stator is suspect. A good stator should be able to keep the motor running.