[cafeGS450]

I'm trying to pinpoint an issue on my 87 GS450L.

When I press the start button all I get is a single click. If I put it in gear and rock it back and forth. Then I put it back in neutral and try to start it again about half the time it will turn over once and then back to the clicking. Am I right in assuming it would be the solenoid?

A side note, when it does turn over it dumps my battery from 75% charge down to 10%. I'm assuming my battery is on it's last leg but I've been using the engine start mode on my charger to avoid that issue. Thanks in advance!

 

[wadenelson]

How do you know it dumps your battery from 75% to 10%?

A fully charged battery is 12.6V or better. 50% discharged is 12.3. Are you seeing less than 12.1? On what? A multimeter? You can't trust a gauge.

If your charge claim holds up, then yes, you need a new batttery.

What you REALLY want to do is voltage drop your starter and solenoid.

Put red meter lead on B+
Put black lead first on solenoid start terminal, and then on starter + terminal

WHILE CRANKING observe the voltage drop indicated on the meter. It should be less than 1V or you have wiring problems, corrosion, loose connections, etc.

Now put the black lead on B-
Red lead on starter + terminal.

WHILE CRANKING battery should not drop below 9V or time for a new battery. This is just a poor man's battery load test.

If headlights dim considerably while cranking, another indication of a weak battery -- esp in a car.

Or just pull the battery out take it down to autoparts store and have 'em test it.

I am assuming you're hoping to put off battery replacement till spring, lol. We all do!

 

[cafeGS450]

Thanks wadenelson for the advice but I think you might be missing my main issue. The starter motor won't turn over and that's when I get a single click while holder the start button. (as if the starter is stuck) it's not until I rock the bike in gear that it sometimes will turn over.

I've tried to eliminate the battery from the equation by using a battery charger with an engine start setting. This is where I'm getting the % numbers from.

 

[wadenelson]

No, it's YOU that doesn't understand. I'm trying to lead you through correctly diagnosing it so you don't buy parts you don't need.

For starters, disconnect that 100 Amp "Engine Start" battery charger just in the hopes you haven't already fried your voltage regulator.

Next, confirm you've got a good battery.

Then do the voltage drop testing I suggested.

After you do that, THEN I'll lead you through testing the solenoid and the starter.

Assuming I'm in a good mood, feeling charitable to noobs coming here begging for help I charge customers $90 an hour for...

 

[Eye_m_no_angel]

Wade is giving you the right dope, cafe. In your situation you've got to make sure you don't have a bad battery or a wiring issue before you can diagnose the starter problem, and using a jump start feature on a charger is not a reliable substitute for a good battery.

The problem's you are describing do, in fact, sound like a weak battery, but it could also be the starter clutch, solenoid, or several other things. The first step is to eliminate the battery as a problem.

 

[Stablefull]

This is a recurring theme l read on these threads...it seems like many times when there is any kind of starting issue, the experienced mechanics always say this...make sure your battery is good before yopu look at anything else. Good to know

BTW, while we are on the subject, someone was talking about a really good battery that lasts like 5 years or more. Anyone know what it's called?

 

[Eye_m_no_angel]

There are a lot of contributing factors to battery life, so it's kind of hard to peg one brand as better then others. Sometimes it's a problem with the bike, or the owner, that causes a battery to fail before it should.

Deka makes the best larger sized motorcycle batteries that I have found so far. I haven't seen any battery that lasts as long in a larger bike with a healthy charging system as a Deka.

Yuasa also makes a good battery, and is very popular for metric bikes that have a smaller battery compartment.

 

[Stablefull]

Okay, l have heard of the Yuasa battery. That name always seems to come up in battery threads.

It seems to me, though, that there was one battery that was kind of the consensus best-battery-you-can-buy, that would last like 5 or 6 years as long as you kept them on a tender, and that they were fairly expensive but worth the money.

 

[Eye_m_no_angel]

Well, like I said, the Deka is the best battery I have ever found, and they routinely last 5-6 years. (They make the OEM Harley batteries.)

In fact, just before vacation this year the battery in my Roadking was just starting to act a little weak, so I thought, "better safe then sorry," and replaced it. After I got back and was taking it to the dump I looked at the date on the battery and realized it was 9 years old! And I'm very forgetful about putting it on the tender.

Deka also makes a battery labeled as "The Big Crank," but I've never used one under that name.

 

[MONI]

I'm surprised you ever use a tender Eye. I would have thought you were able to ride enough to not need one. We only use them in cold/winter months. At least it was that way until this year. We've already told the kids that we were taking a vacation next summer. We might also go with them on theirs but we want at least 1 week to ourselves and may end up wanting 2.

 

[Stablefull]

Thanks for the info eye. Does Deka make a battery for sport bikes, or just the big cruisers?

 

[Eye_m_no_angel]

You'd have to call them, or look at their website. I've never bought a sport bike battery.

 

[Stablefull]

Gotcha...okay, thanks for the tip