[Dennis Peacock]

Yesterday my son tried to start up his 1995 VT1100 to go to work, the motor tried to turn over once or twice but that was it. It never cranked up until he put a battery charger on it and started it with the battery hooked up to the charger. It never does that in the spring, summer, or fall. In those months it usually starts right up when you choke it. But when the outside temps drop to below 40 degrees, the bike doesn't like to start unless the motor is warm. Could it be that there is a slow power drain somewhere that's causing the plugs to not spark properly? Besides a battery tender attachment so he can plug the battery up to a battery tender, there isn't anything else hooked up to the battery.

 

[7xclm]

If the key is off no power is available for the bikes electrical system. 2 questions. 1. What is the battery voltage with the key off. 2. How low does the battery voltage drop when trying to start the bike.

 

[TenDollarBill]

It sounds like a weak battery. Check the battery voltage based on the procedures in the technical section. Check all the electrical connection to make sure they are clean and tight.

 

[smilie]

How old it the battery? I'd charge and load test it. May just be time for a new one.

 

[GB6049]

Older battery, or one with lower cold cranking amp rating in cold weather makes it harder to start as does a thicker viscosity oil. With no accessories, you are not likely having anything draining the battery. Keep it on a trickle charger over night to ensure you have a fully charged battery in the morning.

 

[Dennis Peacock]

I have put 2 batteries on this bike since we bought it 3 years ago. The first battery got to where it wouldn't start the bike. I bought a battery and put on it and that resolved the issue. The issue showed up again last spring when we were getting ready to take a motorcycle senior trip for his graduation. I replaced the battery again last spring and now it's doing it again.

The bike stays in my shop with my bike and my other son's bike. Joe's bike is the only bike that we are going through batteries on. I just don't know where the power drain is coming from......to me...it just doesn't seem like a battery issue.

 

[vito]

Check the battery with a volt meter. You'll be able to see if there is a drain on it somewhere.

Check the connections, check the ground to the frame

 

[7xclm]

That is a strange one for sure. Been to Conway several times, it is not like it gets severely cold during the winter months. Do you keep the bike on a battery tender when it is not ridden.

 

[h13man]

What kind/style of battery are you using? Wet cell, AGM, etc.

 

[jpr1968]

If you have a multimeter with D.C. amps, disconnect the negative battery cable and put the meter between the negative battery post and the negative cable. If there is key off battery lose, your meter will show an amp reading. If there is start pulling fuses until there is no amp leakage and then troubleshoot that circuit for a grounded wire. Have you ever troubleshot your charging circuit to make sure it's properly working?

 

[RONW]

Ditto, something like this (ignore the amp number). Per manual, the allowable leakage is very minimum .... 1 milliamp max for older bikes, .1 milli amp max for newer.

if you don't have aftermarket gadgets tapped into your electrical system, it might be a faulty RR. Besides, regulating and rectifying, the RR's diodes prevents the battery from back feeding into the stator's ground when the key is turned OFF. There's a direct path from the battery's positive (+) to the stator. Thus, the diode, a one way check valve, so forth.

 

[Dennis Peacock]

OK. I will do the checks recommended. I have a good meter to check with, I just needed to be pointed in the right direction.

Thanks and I'll post an update once I get the checks done.

 

[Flying Greg]

Mine left me stranded three times, each with a low battery. finally decided it was the RR so I bought the mosfet unit from roadstercyles.com and have not had a battery problem since.

If you do a search under mosfet rr you will get lots of info. I think I have a thread ind there somewhere as well.

 

[John Hopkins]

jpr1968 has given good advice there.. the only thing I can add is, If you are not familiar with digital multimeters before doing the above test make sure you remove the red lead from the V ohms mA socket and plug it into the 10A socket for your first reading, If the electrical circuit has a large current drain the lower socket will destroy the meter... You can always move back down to the lower socket for fine work after the initial reading.

John.

 

[adlowe]

it just doesn't seem like a battery issue.

Then you need to get yourself turned around. There is no doubt it's a battery issue. None. What you need to do is conduct some testing to identify the cause then correct the problem.

For me, the solution to buying two new batteries inside of three years was to stop wasting money on f-ing T-shaped POS and buy a high-quality, Yuasa AGM. It lasted me eight nearly trouble-free years. (It struggled to get me through the lasy September, October and November of riding before I bought a replacement.)

 

["Captain D"]

Question for our Gurus
With the key in the OFF position, the charging system is still hooked up, ain`t it???
As in a diode gone bad in the rectifier can drain the battery, can`t it???
I know > That`s 2 questions ain`t it?
D

 

[RONW]

If you think of the stator/RR as being hardwired to the battery's positive (+) terminal, then a healthy diode (one-way valve) is needed to stop the battery from bleeding back to the stator since the stator is internally grounded (-) and electricity does flow from positive to any negative. If the key was stationed anywhere on those wires, then turning OFF the key would prevent the backfeed. The RR is wired to the battery via the R/W wire that plugs into the starter-relay. The adjacent Red wire on the starter relay is the wire the key is stationed on. The Red wire feeds the fusebox.

 

[adlowe]

With the key in the OFF position, the charging system is still hooked up, ain`t it???
As in a diode gone bad in the rectifier can drain the battery, can`t it???

Yes.

No. R/R diodes aren't doing a thing when the stator is not running. (R/R converts ~150 VAC to ~14 VDC.) The stator is not doing a thing when the engine is not running.

It is possible, in the wildest stretch of the imagination, to have a charging system sufficiently horsed up that it would drain the battery with the key off. (This is true because the charging system is connected to the battery without going through the key.) But it would take something like malicious intent to get it wired this way -- far harder than getting it wired correctly. Of course, you *might* be able to spin the engine backwards through the stator with the key off if you put enough time into figuring out how.

 

[jpr1968]

If you think of the stator/RR as being hardwired to the battery's positive (+) terminal, then a healthy diode (one-way valve) is needed to stop the battery from bleeding back to the stator since the stator is internally grounded (-) and electricity does flow from positive to any negative. If the key was stationed anywhere on those wires, then turning OFF the key would prevent the backfeed. The RR is wired to the battery via the R/W wire that plugs into the starter-relay. The adjacent Red wire on the starter relay is the wire the key is stationed on. The Red wire feeds the fusebox.

If you have a grounded(no such thing as internally grounded) stator, you have a problem. Battery is not going to backffed to the stator.

 

[John Hopkins]

Question for our Gurus
With the key in the OFF position, the charging system is still hooked up, ain`t it???
As in a diode gone bad in the rectifier can drain the battery, can`t it???
I know > That`s 2 questions ain`t it?
D

Forget about whether the key is on or off..the main thick + lead from the battery joins directly to the RW wire as RONW says and this connects to the rec/reg.. now remove every other part of the electrical circuit...the reg/rec is grounded so a fault in the reg/rec could cause a leak straight to ground because the rec part is a simple four diode bridge with capacitors across each diode and a link to ground..that is the easiest path to ground in a fault situation, then the regulator in it's simplest form is a three pin 14 .8 volt regulator which is another pathway to ground, and between them is usually a reservoir capacitor..None of that really matters.. what matters is that in answer to your question..a fault in the rec/reg can drain the battery with the key in the off position.

Edit as jpr1968 said only the casing of the stator is grounded, if the coils were grounded there would be no ac voltage generated.

John.