New to me 1971 r50/5. Starter wasn’t working when I bought it. Kick start is fine. Bike runs just fine. I didn’t do a very good job of trouble shooting and at this point I have bought and installed new Valeo starter, replaced starter relay, and replaced battery. When I push the starter button I just get a “clunk”. Same clunk I got when I purchased the bike. Any input would be very much appreciated.
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Help with starter
- Thread starter dmulac
- Start date
Welcome to the forum and the world of Airheads! I'm not very good with these either, but I wonder if something on the old starter like the solenoid was defective. I think you can take the old starter to motorcycle shop and ask them to put voltage across the starter...or do it yourself if you know how. As for the new starter, is it the proper number of teeth to mesh with the flywheel? There are 8- and 9-tooth starters...the early bikes should have an 8-tooth starter bendix drive.
RPGR90s
Active member
Its best to start at the starter itself. Remove the starter cover and jumper the two big terminals together TEMPORARILY. If the starter spins normally, you then know your problems are upstream. Starter solenoid, Starter relay, Starter relay wire to the starter, Starter button on the right handlebar, etc.
stevenrankin
Well-known member
Before the starter can do its job, it needs voltage and amperage from the battery. First rule of troubleshooting a no start is to check the battery. Is it fully charged? Do you have 11.6 volts at rest?
There is a Load test a battery shop can do that will determine the condition of the battery. They apply a controlled load to the battery to see if it can deliver the proper voltage.
You can do about the same thing by fully charging the battery. Then, if the battery is at 11.5 or so volts, hit the starter button and notice the drop in voltage while the button is engaged. If the battery drops down past 10 volts, either one of two things is going on. One, the battery is shot and not delivering the voltage or two, the starter is binding or shot drawing more than the normal load from the battery. Since you have a new starter, I would assume the battery is shot. LOL, I am sorry if my instructions aren't that clear, it is easier to do than to write about.
Best bet is to take the battery to a shop and have it checked. Good luck, St.
There is a Load test a battery shop can do that will determine the condition of the battery. They apply a controlled load to the battery to see if it can deliver the proper voltage.
You can do about the same thing by fully charging the battery. Then, if the battery is at 11.5 or so volts, hit the starter button and notice the drop in voltage while the button is engaged. If the battery drops down past 10 volts, either one of two things is going on. One, the battery is shot and not delivering the voltage or two, the starter is binding or shot drawing more than the normal load from the battery. Since you have a new starter, I would assume the battery is shot. LOL, I am sorry if my instructions aren't that clear, it is easier to do than to write about.
Best bet is to take the battery to a shop and have it checked. Good luck, St.
RPGR90s
Active member
Remove the small black wire from the starter solenoid. Not the starter relay under the tank, but from the starter solenoid itself. Use your meter and set it to DC volts. Probe the positive meter lead to the black wire (removed) and the black meter lead to frame ground.
Ignition on
Press the starter button
Verify the voltage rises to 12.6vdc or higher.
This verifies that you are getting voltage to pull in the large starter solenoid.
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stevenrankin
Well-known member
Sorry, as usual of late, I didn't see you had replaced the battery. Not to be a bigger nut but did the old starter do the same thing? What made you replace the old starter? They are pretty bullet proof and reliable.
Sadly, there are such things as defective new parts out there. St.
Sadly, there are such things as defective new parts out there. St.
PGlaves
#13338
So the two main components - the starter and the battery are new. So what is between them. The starter relay and cables. If you get a clunk then power is getting to the starter solenoid so it would seem the relay is OK. I vote for high resistance in one or more of the cables for some reason.
stevenrankin
Well-known member
A few years back, Matt of Keep em flying fame had an issue with a starter that fit the bike but was for an oil head and turned in the opposite direction. Are you sure you have the right replacement starter? St.
pauls1150
MOA #24991, south of Los Angeles
Certainly a valid question, but if I recall correctly, that particular starter had been rebuilt with the wrong motor.
If that was the case here - per that article - the engine could still turn over (not just the infamous "clunk"), but it wouldn't start because the timing of the valve action and ignition action would be all wrong.
forums.bmwmoa.org
If that was the case here - per that article - the engine could still turn over (not just the infamous "clunk"), but it wouldn't start because the timing of the valve action and ignition action would be all wrong.
Matt P's Flywheel Issue
In the November ON, Matt talks about a strange alignment (or lack thereof...) of the timing mark on a '92 R100GS. QUESTION: It's been a long time since I've been inside an airhead, so - Is it possible that the factory (or somebody) installed that flywheel "backwards", that is, with the wrong...
forums.bmwmoa.org
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Make sure you check your ground wire and its connections! A bad ground will mess things up every time, you will think its a "positive" problem only to find out later it was on the ground side of the electrical system. That's why most ground tabs and connections are larger than the positive connections.
stevenrankin
Well-known member
Lots of ideas as to what is possibly wrong, any updates?
