electrical issues...

[hoopcatjc]

I'm the proud owner of a GS450T and I'm trying to be my own mechanic but my electrical system still confounds me. Here's what is at issue...fresh battery, lights and horn all work when ignition is on. There is a loud click when thumbing the starter button but nothing else. I've removed the component behind the left side panel that the battery cable goes into
(alternator?)....I noticed that the cable leaving this device and disappearing into the engine case was warm to the touch. Is this a bad alternator? or starter maybe? Thanks in advance for the help, the weather is getting warm and I'm anxious to ride....

 

[adamgagne]

Your alternator has nothing to do with the bike starting, only keeping the battery charged.
Try tapping on the starter with a screwdriver while holding the starter button for a few seconds, if it begins to turn even slowly, the starter is your problem.
Also put a voltmeter lead on the electrical terminal going into the starter, and a lead on some bare metal on the frame and what voltage you get, you should get pretty close to 12V, regardless of the starter motors condition.
The starter may have to be rebuilt, or at least get new brushes. I got a rebuilt starter for my gs850 for $100 (compared to $350 for a new one).
If you take out the starter and open it up you can usually look at the brushes and tell pretty quick if it is bad.

 

[Steve]

That "thing behind the left panel" is the starter relay or solenoid. All it is is a remote-control heavy-duty switch. When you push the starter button, it activates the relay to send a LOT of current to the starter.

If the starter cable is getting warm, it tells me that the connections might be good, and the starter itself might be bad. Open the cover over the starter, locate a couple of bolts you will find under there and make sure they are tight first. If they are loose, that might be your problem as that is how the starter is grounded. If they are already tight, remove them, remove the starter and check to see if it spins freely.

You can also apply power directly to the starter, but make sure you hang on to it as it will try to twist out of your grip. If you are real adventurous, you can take the starter apart to check the brushes and bearings. Parts are available for most of these items.

By the way, SOME of these starters are interchangeable. I used an extra starter from a 450 on a 650. Comparing the number stamped on the housing showed no difference, so if you decide to just replace the starter, you might have more options.

Happy wrenching.

 

[DimitriT]

Have you been able to bump start it?

 

[hoopcatjc]

thanks for all the valuable info....A friend of mine suggested removing the starter, putting it on the ground with a foot on it, and using battery cables....neg to the starter body and pos to the pos battery terminal to check starter integrity......anyone have any luck with this procedure?

 

[odl777]

ive tried it but i think you have to make sure the starter is grounded. My starter was out because once i got it grounded it barley turned. good luck

 

[Boondocks]

...Here's what is at issue...fresh battery, lights and horn all work when ignition is on. There is a loud click when thumbing the starter button but nothing else....

I had the same problem. The click is the starter solenoid switch contacts engaging. I had lots of clicking but no (or very weak) starter action. In my case, the brushes in the starter were sticking in their holders and not making solid contact with the commutator. I removed the starter cover and lightly tapped on the starter with a small ball peen hammer (with the starter button pressed and the clutch lever tied back). I was relieved to find that this would activate the starter. It gradually got better although I had to repeat the tapping a few times. I never did take the starter apart and it works great now with no problems at all for over a year. I have a backup starter in case I want to replace it, or I may just put new brushes in if required at some point. It's working like new now, so I prefer to let a sleeping dog lie.

You may not be so lucky, but as adamgagne has suggested, at least you will have identified the starter as the culprit if the tapping activates it.

 

[hoopcatjc]

During a little pre-planning, it's apparent that to get to the starter, you've got to remove the tank, carbs, and cam chain tensioner to get to the starter.
Is there an easier method? Thanks again for all the replies and good advice.