• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

  • Beginning April 1st, and running through April 30th, there is a new 2024 BMW MOA Election discussion area within The Club section of the forum. Within this forum area is also a sticky post that provides the ground rules for participating in the Election forum area. Also, the candidates statements are provided. Please read before joining the conversation, because the rules are very specific to maintain civility.

    The Election forum is here: Election Forum

99R1100RT starting electrical gremlins

K

khfranck

Member
I’d appreciate your help troubleshooting.

Bike has ~80k miles with the last ~10k mine.

Battery (approx 2 years old) kept getting weak but it would strong up on the battery tender. I’d hear the squeaks of the alternator belt on starting. So early this past week I changed the alternator belt. Didn’t help so I replaced the battery, too. (Yay Beemer Boneyard)

Ran great for the rest of the week local to build trust. Then took it a couple hours away on Thursday for a little trip. Super! Good stops and starts. But then this AM weak battery no start. Dash lights strong and the fan for the LED headlight string. I was far from my battery tender so I bump started it and got home. Tried to start after all that alternator charging and the starter motor engages but no crank.

Voltage on the battery when sitting is 12.3. When the starter is attempted voltage drops to 6 V.

Reckon bad starter wiring / connectors or starter itself?

Thanks for your collective wisdom.


Sent from my iPhone using Tapatalk
 
I should say previous owner reportedly changed Hall sensor. And I believe it since it was well maintained and it’s only a start problem.


Sent from my iPhone using Tapatalk
 
khfranck said:
I’d appreciate your help troubleshooting.

Bike has ~80k miles with the last ~10k mine.

Battery (approx 2 years old) kept getting weak but it would strong up on the battery tender. I’d hear the squeaks of the alternator belt on starting. So early this past week I changed the alternator belt. Didn’t help so I replaced the battery, too. (Yay Beemer Boneyard)

Ran great for the rest of the week local to build trust. Then took it a couple hours away on Thursday for a little trip. Super! Good stops and starts. But then this AM weak battery no start. Dash lights strong and the fan for the LED headlight string. I was far from my battery tender so I bump started it and got home. Tried to start after all that alternator charging and the starter motor engages but no crank.

Voltage on the battery when sitting is 12.3. When the starter is attempted voltage drops to 6 V.

Reckon bad starter wiring / connectors or starter itself?

Thanks for your collective wisdom.


Sent from my iPhone using Tapatalk
Click to expand...

Sounds like it’s time for a battery. Voltage dropping below around 9.2 volts while cranking is a no-start condition.
You can verify this by jumping the bike as you would a car. The Battery Tender won’t do it and it isn’t good and may ruin the BT.
OM
 
I suspect starter drag - either because the nose bushing is worn or because a magnet has come loose. Does attempting to start the bike cause an ABS fault?

With a fully charged battery what is the voltage key off?

What is the voltage key on?

What is the voltage with the starter cranking or otherwise with the start button depressed?
 
khfranck said:
Voltage key on 12.3. Starter engaged 6 something. New battery this week.


Sent from my iPhone using Tapatalk
Click to expand...

You almost certainly have a defective starter. If it was a bad connection it would not pull the voltage down that far. I suspect a loose magnet.
 
Great video. Tested it like the video and the starter failed. New one on order!!

92e51090235348e4f9342c399622bbe2.jpg



Sent from my iPhone using Tapatalk
 
Great!
That "squeak" during starting may not have been the alternator belt - it's also a sign that the inside of the starter's nose is dry and/or dirty.
 
You must log in or register to reply here.

Similar threads

A
2004 R1150R No Start - Has spark, fuel, turns over, and replaced HES
Replies
5
Views
1K
gsaddict
gsaddict
VIEJO
2003 K1200RS Electrical Mystery
Replies
6
Views
1K
VIEJO
VIEJO
1
R1200RT Won't Start
Replies
4
Views
1K
brownie0486
brownie0486
A
2004 R1150RT: iABS issues, Bubbles in the Funnel tool...
Replies
6
Views
2K
adriancw
A
Pasta_Mouse
New guy from the PNW, San Juan County.
Replies
5
Views
655
langoptc
langoptc
Back
Top