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murty

New member
When I went to start my 1994 R100R that has not run in a month or so and has been on a battery tender the entire time, I turned the key on and the indicator lights all came on as normal but when I pressed the start button the starter motor engaged for a fraction of a second then everything went dead.

  • None of the dashboard indicator lights illuminate when the key is turned on.
  • Battery connections are clean and tight.
  • I put it back on the battery tender and it is flashing green indicating ok.
  • Also with the ignition on sometimes the tach needle with rise and fall slightly.
  • And with the ignition on and kill switch moved from run to off, the bike makes a faint buzzing noise from the general vicinity of the battery.
  • Prior to this episode the bike has been starting and running great.

    Any troubleshooting suggestions are welcome.

    Thanks in advance.
 
Doesn’t really make much difference if tender was attached if the battery is old enough to be at the end of its life.

It’s almost always the battery. The only other likely thing is the starter relay.

Here’s how my recently failed battery acted ... could start the bike no problem. Could turn motor off and try to restart ... nothing. Just one example. They usually go quick, no warning.
 
Agree on the battery. In 30 years of being a service advisor when I heard your description the battery was bad probably 95% if the time. I'm personally sold on the Odyssey agm batteries-have had great experience with them & have Odysseys on both of my airheads (one is a '94 R100RT).
 
I would first look at the starter relay. If the terminals have some corrosion, the starter solenoid might not get power.
 
Summer heat must be really hard on batteries. I've had two instances lately. Different days, when a friend had ridden the bike then shut it down. And the bike would not restart. No lights, nothing. Neither battery would take a charge. In both cases a new battery fixed the problem. The interesting thing for me is that there was absolutely no warning in either case.
 
Summer heat must be really hard on batteries. I've had two instances lately. Different days, when a friend had ridden the bike then shut it down. And the bike would not restart. No lights, nothing. Neither battery would take a charge. In both cases a new battery fixed the problem. The interesting thing for me is that there was absolutely no warning in either case.

That is typical of today's fragile AGM batteries.
 
Whenever I get a click but no go situation and I am fairly certain it should be in a fully charged state the very first thing I do is load test the battery. It doesn't matter what the volt meter tells me in the event that I check voltage first. If it is over 12V great but that only means it _might_ be OK. If I load test it and the voltage drops below 10V the battery needs to be replaced.

If the battery tests OK then I start with pulling the starter relay and cleaning the terminals along with tightening them up with a gentle squeeze of the pliers on the female spade connectors to insure a good fit.

If that is all OK I remove the starter cover and check the voltage on the black wire to the solenoid while pressing the starter button. If there is 12V there you may have a solenoid connection issue, solenoid issue or starter motor issue assuming the connection is good.

Make sure the heavy gauge starter cable and your ground cable have good connections as well. Do all these things before you start swapping expensive parts.
 
Update

Thanks for all the helpful advice - much appreciated! I just got the bike back home where I can work on it. The battery voltage is 12.78v. When I turn the ignition key to ON none of the dash indicator lights illuminate. Also nothing else works - horn, signals etc.

I read somewhere that there is a relay that switches power to the entire electrical system - is that true? Where is it located? Any other troubleshooting advice?

Thanks,
Paul
 
There is not a power-all-on relay. But there's the small starter relay under the tank. It turns off the headlight when you push the starter button. But this relay would not power off the dash lights nor the horn when you push the starter button.

Did you check the three - and only -fuses?

/Guenther
 
I would check that starter relay, and the wires going to and from it. Even though the relay doesn't control those other electrics, I believe the main power wire goes to the starter relay and then branches back to the rest of the bike. Known problem that sometimes the main power wire gets separated at the relay.
 
The symptoms continue to be those of a bad connection. How did you ascertain the battery connections are "clean and tight?" Just looking isn't enough.

The only way to know that the connections are good is to remove all the connections, at both ends of every wire or cable connected to the battery and the starter. Clean the connectors and their posts. Reassemble.
 
I was talking about the small relay which sits under the tank together with the other relays. It gets its power straight from the battery and is not fused(!) and always hot. It only prevents you from starting the motor when neither in neutral nor the clutch pulled.

The relay/solenoid attached to the starter gets its power straight from the battery via the thick red wire.

All other electrics get their power from the ignition switch passing through either of 4(!) fuses. Easy to check without even looking at the fuses.

With ignition on...
- does the break light come on? (fuse #1)
- is the tail light on? (fuse #2)
- does the clock work or do you measure ~12 volts at the accessory socket? (fuse #3)
- does the horn work? (fuse #4)

If none works then have the battery tested at an auto parts store.

If the battery is ok then it might be problem with the ignition switch.

/Guenther
 
There is not a power-all-on relay. But there's the small starter relay under the tank. It turns off the headlight when you push the starter button. But this relay would not power off the dash lights nor the horn when you push the starter button.

Did you check the three - and only -fuses?

/Guenther

Yes, this bike has four fuses. One was blown, and I replaced it but the condition is unchanged.
 
Fuse

If you replaced the blown fuse with another and it too blows, you have a short in the system somewhere.

A blown fuse can also mean an overload or draw of current in a system.

Have you found a wiring diagram for the bike?

Short circuits can happen in a lot of places. Over draw of current in a starter system can be one of two things, a poor connection or dirty connection in the system or a bad starter.

I don't remember much from my early days as a mechanic but I remember in some cases a bad battery when the starter is cranked, will cause a spike in amperage and drop in voltage.

A load test of the battery is the only proper way to test it. It can have 12 volts while sitting with no load, When a load is put on it, it can drop too as much as 2 volts depending on how many cells are still good. St.
 
murty, it seems you expect others to have a spiritual connection with your bike...I don't have that! :scratch

One was blown

It would definitely help to know which one blew by the numbers I gave in an earlier reply. :wave

So all four circuits protected by fuses work (according to the tests I gave in my earlier reply)?

With ignition on, is the low beam on?

/Guenther
 
Number 3 fuse

murty, it seems you expect others to have a spiritual connection with your bike...I don't have that! :scratch


It would definitely help to know which one blew by the numbers I gave in an earlier reply. :wave

So all four circuits protected by fuses work (according to the tests I gave in my earlier reply)?

With ignition on, is the low beam on?

/Guenther


Hello Guenther, counting from left to right it was number 3 that was blown.

Best,
Murty
 
With ignition on...

murty, it seems you expect others to have a spiritual connection with your bike...I don't have that! :scratch



It would definitely help to know which one blew by the numbers I gave in an earlier reply. :wave

So all four circuits protected by fuses work (according to the tests I gave in my earlier reply)?

With ignition on, is the low beam on?

/Guenther

With ignition on there are no lights, no dash indicator lights, horn, turn signals don't work.
 
Problem solved

I had the battery load tested, it failed and I replaced it with a new one - problem solved. Thanks for all the helpful advice!
 
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