Intermittant starter switch

Oy. Someone tell me there's an easy fix for this. My starter button has become intermittant. I'll get on the bike, flip the kill switch to on, turn the key, grab the clutch, hit the starter button, and.... nothing. This will happen a few times, then all of the sudden it will work. It doesn't appear to be a battery issue or anything, because once it works, there seems to be plenty of juice available to turn the engine over.

Please, let it be just a dirty contact or something I can clean or tweak easily.

Could be any of the electrical contacts...from a grungy clutch switch to worn contacts in the keyed switch. Isn't there a relay under the tank too?

Good luck hunting them down, maybe slow down on selling the 650?

Very few things about fixing bikes are as aggravating as an intermittant electrical gremlin.

Steve

sgborgstrom said:

Good luck hunting them down, maybe slow down on selling the 650?

Click to expand...

Couldn't be any slower.

Sometimes a wire will have an open in it from where it was zip tied too tight, folded over, or pinched. While holding down your starter button, move your handle bars back and forth. I'd also actually grab some of the wiring harness going up to your handle bars and wiggle it around where ever you can get to it, again while holding the starter button down, anticipating it to turn over. Good luck, hopefully its an easier fix than that.

You have several "switches" in play, as well as several connections.

If it fails to crank in gear with the clutch pulled try neutral. That may identify ithe problem as the clutch switch.

If it fails to crank, try flicking the kill switch back and forth a few times. If that seems to work then that switch needs cleaning.

Also try the ignition switch (key) on off on off and see if that changes anything.

Then use a good electrical cleaner to clean what you can get to.

Okay, I tried all of these things, and nothing makes much of a difference. (I didn't try grabbing the harness or moving the bars yet, though.)

When I hit the starter button, I can hear the relay clicking.

One thing that did seem to make a difference was snapping the throttle all the way shut. Is there a switch on the throttle that's supposed to know when it's shut?

Hello; My guess would be the starter relay under the tank. The hold in coil doesn't have enough power to make the connection to the starter. It's an easy fix, about $14, just pull out the old one and stick in the new one.

I currently have the same problem with my VW Van.

jmerlino said:

Okay, I tried all of these things, and nothing makes much of a difference. (I didn't try grabbing the harness or moving the bars yet, though.)

When I hit the starter button, I can hear the relay clicking.

One thing that did seem to make a difference was snapping the throttle all the way shut. Is there a switch on the throttle that's supposed to know when it's shut?

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I think you have isolated the problem. If you hear the relay clicking then all of the switches are working and the signal current is getting to the relay. So, either a relay connection or battery connection is bad, battery is weak, or the relay is bad.

PGlaves said:

I think you have isolated the problem. If you hear the relay clicking then all of the switches are working and the signal current is getting to the relay. So, either a relay connection or battery connection is bad, battery is weak, or the relay is bad.

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Well, I'm starting to think the battery was the problem. I put it on the charger last night in anticipation of a ride this morning, and it started right up. If the problem reappears when I know the battery is fully charged, I'll replace the relay.

But this raises an interesting question: In as much as this was happening post-ride, could I have a problem with the charging system? Or could my battery just have been so low that even a good long ride wasn't able to fully charge it? OR, could it have been a combination of a somewhat depleted battery AND a flaky relay combining to make the problem intermittent - then when the battery was fully charged, it had enough juice to overcome whatever the problem was with the battery?

I had a similar problem...

...and got a lot of great suggestions from the folks here. My starter didn't want to go when the bike was warm. You could hear the relay kick in, but the starter sometimes wouldn't go, just like it wasn't getting enough juice.

Cold, no problem. My bike is an incredibly easy starter, if the engine turns over, it will go. I ended up cleaning as many electrical connections as I could, I replaced the battery (it was 5 years old, lead/acid type), and voila! No more problems. I suspect that the new battery is probably masking the problem for now, but no issues at all.

Braddog said:

...and got a lot of great suggestions from the folks here. My starter didn't want to go when the bike was warm. You could hear the relay kick in, but the starter sometimes wouldn't go, just like it wasn't getting enough juice.

Cold, no problem. My bike is an incredibly easy starter, if the engine turns over, it will go. I ended up cleaning as many electrical connections as I could, I replaced the battery (it was 5 years old, lead/acid type), and voila! No more problems. I suspect that the new battery is probably masking the problem for now, but no issues at all.

Click to expand...

Well, my bike started fine all day today - warm or cold. It's got a Westco AGM battery in it. Don't know how old it is.

Airheads have some notorious problems. We learn to live with some of them, and others need a permanent fix. I've discovered that what appears to be a bad switch may be a poor relay connection or loose connection inside the headlight shell.

Note the starter protection relay (under the tank, left side, above timing case) is a plug-in relay (small black box). The female terminals on the wire harness where the relay plugs in can easily collect water and grit, and can corrode just from salt air. The temporary fix is to pull the relay and carefully clean each contact, then grease the terminals with some non-conductive grease (Vaseline works fine) to prevent more corrosion.

The relays don't last forever, and when the internal contacts get worn or burned, the relay will do funny things--such as only dim the headlight when starting, but not turn it off, or not allow the starter solenoid to function. The best reason for just installing a new relay is clean contacts.

I got so frustrated with intermittent starting that I completely removed the stock relay and connector plug and hard wired in a more reliable relay. Sorry, don't have the number anymore.

Depending on model, the neutral switch and the clutch switch must be working to allow the starter relay to function. Sometimes the neutral switch fails, but if you always squeeze the clutch anyway when starting, you don't realize it has failed. Then one day the clutch switch starts to fail too, and nothing works.

Relays depend upon adequate voltage. If the battery is low, there may not be enough current to hold the relay closed and also crank the engine. Airhead charging systems are (we're all embarrassed to say) not very powerful, and not very reliable. Even if the alternator and regulator are working like new, a failing battery will cause problems. If you sit at a traffic light on your way home with headlight and brakelight on, the battery can discharge enough to cause problems. Best practice to maintain a battery is to plug in an automatic charger whenever the bike isn't being used. That keeps the battery fully charged for maximum voltage and long life. My favorite charger is the Battery Doc.

When you get frustrated enough with the stock charging system, you'll spend the big bucks to install an Omega 400W system, similar to the K bikes.

The connections inside the headlight shell can also become corroded or loose and cause intermittent opens. So, consult a good wiring diagram, figure out which connections are related to the starting circuits, and make sure the connections are good. Pull the connectors one at a time (a pair of small needle nose pliars is helpful. If any connector is easy to pull off, detach it and VERY care fully close up the female contacts with pliars, so that the connector takes a bit of a shove to get it inserted.

Don't forget to check the fuse contacts, which are at the top of the rows of connectors. Remove each fuse, and clean the contacts. Fine sandpaper is acceptable--just be sure and clean out any grit (spraying WD 40 will work) Apply a light coat of lubricant (Vaseline is OK) to prevent future corrosion.

Been there, done that.

pmdave

Starter

It may well be a gummed-up bendix assembly. The German grease they use turns to cement in several years. With a Bosch, I believe you can take the bendix apart easily; with a Valeo, you have to drill out a couple of rivets to disassemble the bendix. Clean out the old gunk, re-grease and re-install. I believe I have used small machine screws where the rivets went. When the affliction occurs, you can hit the starter button, hear the relay clicking, but no action. It's 'cause the bendix is frozen. (The bendix assembly is the solenoid that pulls the starter gear into mesh with the flywheel. It's a big-ass solenoid with some mechanical partz)

Before disassembling the starter check to isolate that unit by directly powering the starter. I f it is in the starter when you open it you might find it's the contacts. These are in the rear of the starter and over the years they "corrode" after having years of service. Clean the face with an eraser and it won't act up for another twenty years. I've done this as soon as the first relay click, click,click on all three bikes. Two geese and one BMW.