Starter stuck on

[aces928]

I started my 1990 K75RT and the starter would not stop. I shut off the kill switch and ignition. I could not get it to stop until I disconnected the battery. Any ideas?

[rdalland]

http://www.bmwmoa.org/forum/showthread.php?t=25882

[cjack]

I started my 1990 K75RT and the starter would not stop. I shut off the kill switch and ignition. I could not get it to stop until I disconnected the battery. Any ideas?

The starter relay is welded due to probably a low battery. Sometimes you can, after you make sure your battery is fully charged...before you hook up the battery ground, turn on the ignition, etc. and just after hooking up the rest of the battery...the ground wire, push the starter button sharply several times. Often that will cause the starter relay to release saving lifting the tank and tapping on the relay or having to replace it.
Worth a try.

[manybikes]

Had the same thing happen to my K75s.
It was a stuck relay.
Very inexpensive fix.

[deilenberger]

I believe I'm going to "Stickie" this - since it comes up about weekly..

[CustomSarge]

Took 3 tries, built my own solid state version. Been running V3 since '02 & never looked back. It's considered an "unconventional" answer :stick , oh well... <<<)))

[aces928]

I took the advice, charged the battery and tapped on the relay. It fired right up and is working fine. Thanks to everyone who gave their advice an opinion. :clap

[cjack]

Took 3 tries, built my own solid state version. Been running V3 since '02 & never looked back. It's considered an "unconventional" answer :stick , oh well... <<<)))

BMW built an update for the relay as well. In the form of a kit which has a circuit to not allow the relay to function if the battery voltage is too low. The update was specified for the K1200LT, but of course could be adapted to any K bike with this same relay. The kit was a little pricy...I think maybe just under $175 a while ago. It consisted of a socket with wiring harness and a new relay...and instructions.

[CustomSarge]

While good that BMW addressed the problem, the relay won't even try to start the engine on a weakened battery.

Solid state drivers will feed whatever power the battery has, the trick is in protecting the drivers from heat damage. Anyone interested can email me, I'll send them schematic & description. L8R <<<)))

[cjack]

While good that BMW addressed the problem, the relay won't even try to start the engine on a weakened battery.

Solid state drivers will feed whatever power the battery has, the trick is in protecting the drivers from heat damage. Anyone interested can email me, I'll send them schematic & description. L8R <<<)))

Interesting. But, I guess the relay is much cheaper and easier to implement...anyway, on the newest bikes they still use a relay. With some circuit in it to prevent low battery starts.
I won't be changing over on the K12Ses, but would be interested in the schematic and will email you. Thanks very much.

[BuddingGeezer]

1/2 price relay http://www.texasindustrialelectric.com/relays_0332002150.asp

Ralph Sims

[jrcklbstr]

Sounds like the same problem I'm having. I have heard that when you try to start the bike with the battery not fully charged, the starter relay does not properly engage and the relay might stick "on". I am told the only fix is to replace the starter relay.

[Bobmws]

Sounds like the same problem I'm having. I have heard that when you try to start the bike with the battery not fully charged, the starter relay does not properly engage and the relay might stick "on". I am told the only fix is to replace the starter relay.

You can remove the cover from the relay and file the contacts smooth again. Be sure to charge or replace your battery before trying to restart the bike.

[moeman34]

You guys are GREAT.

I bought my first BMW (00 K1200lt-c) at an insurance salvage auction. It had a stuck starter and I was afraid it had major electrical issues. Nope. After reading your repley and a new $90 relay, she is on the road.

Thanks a million.

Moeman34.....Idaho

[boxerr]

My 1st experience with a K bike:cry
Bloke needed help with his K75RT with ignition problem, wrongly diagnosed, and he bought a new ignition switch thinking that was the problem.
Turned out to be the relay stuck. I dismantled it, cleaned the contacts, and presto, it now starts, and stops as it should.:D

Thanks to this thread, helped me save him some money.:bow

[vectorprime27]

First of all, I really appreciate the tips for getting this fixed. I also ran the battery down (all the way, no less) and suffered the ill-fated stuck starter. I charged the battery, and tried again, but none of the tricks worked. I thought I was going to be resigned to hunting down that darn relay to bang on it or pry it open, when the local BMW mechanic gave me this routine. He said it works EVERY time. He was right, as it worked first try for me.


1. With negative cable disconnected charge battery to full. If it's an old or bad battery that won't take a full charge, replace it before going to the next step.
2. After battery is fully charged, with key on, hold starter button down, and then reconnect the neg. battery.
3. As soon as you connect the battery, the bike should start. After the bike starts, release the starter button.
4. With the bike running, tap the starter button once or twice QUICKLY.
5. Turn the bike off, and she's all fixed.


I hope this helps!

[cjack]

First of all, I really appreciate the tips for getting this fixed. I also ran the battery down (all the way, no less) and suffered the ill-fated stuck starter. I charged the battery, and tried again, but none of the tricks worked. I thought I was going to be resigned to hunting down that darn relay to bang on it or pry it open, when the local BMW mechanic gave me this routine. He said it works EVERY time. He was right, as it worked first try for me.


1. With negative cable disconnected charge battery to full. If it's an old or bad battery that won't take a full charge, replace it before going to the next step.
2. After battery is fully charged, with key on, hold starter button down, and then reconnect the neg. battery.
3. As soon as you connect the battery, the bike should start. After the bike starts, release the starter button.
4. With the bike running, tap the starter button once or twice QUICKLY.
5. Turn the bike off, and she's all fixed.


I hope this helps!


That does work sometimes. I have done it by having everything ready, ign on, connecting the ground cable and just tapping the starter button then. Seems to pull on the contacts and free them.

[138622]

Sometimes my starter on my 87LT gives me cause for worry. It occasionally sounds like it is ready to stall out before it decides to spin the engine. Almost like it has to do a half revolution before it is ready to put out max torque. Anybody have a similar complaint? What could be the cause? And does the fuel pump always whine a little?

[cjack]

Could be you need to clean the brush/commutator area. Or new brushes.

[JHGilbert]

Locating the relay and giving it a rap was the fix for mine. Even with a just filled tank. Although, I'm not sure why my relay stuck with a year old battery at the end of a hour ride. Battery should have been fully charged. Better check the electrolyte level.

[timmyd]

Charge /replace the battery, with batt disconnected, remove starter relay and relay cover. Use a points file to square the contacts and recheck the gap. It only happens with old or discharged battery.(long drain,low output). Your other's diamond nail file works great 'til they catch you. Maintain your batt.

[SueK75]

I started my 1990 K75RT and the starter would not stop. I shut off the kill switch and ignition. I could not get it to stop until I disconnected the battery. Any ideas?

Most likely your starter relay welded. Usual cause is a low or failing battery. The only thing to do is disconnect the battery ground. Sometimes a sharp knock with a hammer handle will free it. You are not trying to crush the relay, just a sharp but not powerful blow. Personally, I always carry a spare starter relay in case it won't free. Best defense is scrupulous battery maintenance and always keeping it charged.
Sue