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71 R75/5 Starter Relay - should I retrofit a new one?

H

htwashere

New member
Greetings MOA mates, I currently have a starter issue on my R75/5: When I click the starter switch, the starter will start cranking but will not stop until I pull the battery. I am still in troubleshooting phase and have done my usual web research (I am new at Airheads maintenance). A lot of advice has mentioned the modifying to the relay as per Snowbum's advice: http://bmwmotorcycletech.info/slash5cricket.htm.

I just purchased this bike not too long ago and both the starter relay and starter switch have been replaced. I have inspected these parts and both look to be OEM equipment. The relay is SR9570 (1-350775) as per specs, it even says manufactured in 2016, made in Germany! The wiring colour code appears to match everything I can find on the internet, so I am not sure yet what the problem might be.

My first question is, since it is so new, should I still crack it open and do the retrofitting? As soon as time permits, I will still go ahead to check all the testing on the relay, wiring and starter switch etc first but I am just wondering if Snowbum's recommendation is applicable to older relays only?

Thanks first.
Henry
 
I'm not sure if the SR9570 is an OEM relay (ie, big $$) or if it's aftermarket. If aftermarket it might not cost much to play with. Snowbum has some suggestions on that page where he says that any 12v relay can be used with some modifications.

Also, on that page, at the very bottom, he indicates there is a test for the anti-start feature. Maybe you could do the test to convince yourself that the relay is or is not the problem.

---Update---

Turns out the SR9570 may be OEM. But EME sells this kit which contains what is needed to convert the original relay:

http://www.euromotoelectrics.com/Relay-12411350775-modification-p/rel-775mod.htm
 
From my dealer quoting the KTM notice:

“Due to market feedback, KTM North America, Inc. has found that on the select models listed above there is a possibility that the fuel filters and/or fuel pump motor could cause a lower than recommended fuel pressure which could decrease the performance of the engine. To aid in preventing a fuel pressure decrease, a replacement kit for the fuel pump has been specially developed consisting of new seals, gaskets, filters and pump motor to stabilize and maintain recommended operating fuel pressure.



KTM North America, Inc. is recommending that the fuel pump motor is replaced on all affected motorcycles including the current inventory prior to PDI following the procedures given later in this document. Please contact all of your customers who own affected motorcycles to have the fuel pump motor replacement kit installed as soon as possible.”

The dealer also noted there was no reason to stop riding as there is no safety issue.
 
Looks to me that Snobum's article is not about the condition you are describing. The starter has a solenoid on it I would pull the unit and open and clean the solenoid and inspect the contacts. On an auto the bendix gear throws the solenoid back disengaging the current source when it starts. There is linkage between the solenoid and starter gear, that could be gummed up, pivot pin worn, etc.

When you first described the problem sticking or pitted contacts came to mind
 
Hi all, thanks for your advice. Here is an update. I found this very useful journal: http://www.bmbikes.org.uk/Forum/viewtopic.php?t=25219 and has a test for me to check if my relay is in working order. So I removed the lead #87 (to the solenoid), connect to a test lamp instead and there is a 3-step test there and my relay has passed all those test steps. I can also stop/start with my starter switch at will (connected to test lamp). But, as soon as I connect back to the solenoid, then the condition occurs again - I basically cannot stop the starter until I remove the battery terminal :(. Snowbum's article did explain that mystery can occur when the battery is either weakened or, the bike is being started in cold climate. Well both currently applies to me: I live in Eastern Canada (10 Celsius currently) and my battery has been drained due to all the starting these days. I am trickle charging it now. I will re-read Snowbum's journal to see what else I might have missed.

I am thinking of two options: either I crack open the relay, go ahead with the surgery and retry or, go get a cheap relay, rewire and test it again.

@200774: the relay looks very much like genuine part or at a minimum: it looks just like the one in Euro MotorElectric: http://www.euromotoelectrics.com/product-p/rel-775.htm

I will update you all if I make any progress. Thanks.
 
htwashere said:
Hi all, thanks for your advice. Here is an update. I found this very useful journal: http://www.bmbikes.org.uk/Forum/viewtopic.php?t=25219 and has a test for me to check if my relay is in working order. So I removed the lead #87 (to the solenoid), connect to a test lamp instead and there is a 3-step test there and my relay has passed all those test steps. I can also stop/start with my starter switch at will (connected to test lamp). But, as soon as I connect back to the solenoid, then the condition occurs again - I basically cannot stop the starter until I remove the battery terminal :(. Snowbum's article did explain that mystery can occur when the battery is either weakened or, the bike is being started in cold climate. Well both currently applies to me: I live in Eastern Canada (10 Celsius currently) and my battery has been drained due to all the starting these days. I am trickle charging it now. I will re-read Snowbum's journal to see what else I might have missed.

I am thinking of two options: either I crack open the relay, go ahead with the surgery and retry or, go get a cheap relay, rewire and test it again.

@200774: the relay looks very much like genuine part or at a minimum: it looks just like the one in Euro MotorElectric: http://www.euromotoelectrics.com/product-p/rel-775.htm

I will update you all if I make any progress. Thanks.
Click to expand...

I am fairly sure the issue is a sticking solenoid on the starter and not a sticking relay. The relay simply triggers the solenoid which when pulled serves as the switch that delivers the high current path to run the starter motor. It also pushes the nose gear but that is not the issuee here. Since bench testing indicates proper relay action until connected to the solenoid it appears to me the solenoid itself is sticking in the "on" position.
 
PGlaves said:
I am fairly sure the issue is a sticking solenoid on the starter and not a sticking relay. The relay simply triggers the solenoid which when pulled serves as the switch that delivers the high current path to run the starter motor. It also pushes the nose gear but that is not the issuee here. Since bench testing indicates proper relay action until connected to the solenoid it appears to me the solenoid itself is sticking in the "on" position.
Click to expand...

Thanks @PGlaves. I'll research on how to troubleshoot the solenoid then. I'll also find a way to bypass the relay to provide current to the solenoid from the starter switch to see if condition occurs. Will keep you folks updated.
 
htwashere said:
Thanks @PGlaves. I'll research on how to troubleshoot the solenoid then. I'll also find a way to bypass the relay to provide current to the solenoid from the starter switch to see if condition occurs. Will keep you folks updated.
Click to expand...

Bike on centerstand, out of gear, ground cable easy to disconnect.

Take a jumper wire from the battery positive post and just touch it to the spade on the starter solenoid. That will energize the solenoid and thus the starter motor. If it sticks and keeps cranking disconnect the battery ground ASAP, but you will have confirmed a sticking solenoid.
 
Hello there, I just wanted to give you an update. I went to pick up a standard $4.00 relay and followed Snowbum's instruction in http://bmwmotorcycletech.info/slash5cricket.htm, and I am able to correct the problem. That is, to start and stop the starter at will. Luckily, my cheap relay has very similar numbering system as the original BMW one, so figuring out the wiring was not too bad. I am going to rule out the solenoid as an issue (for now).

For next step, I will modify the BMW relay per his instruction to see if I can reuse this really expensive OEM part, so that I will have the starter protection feature. Thanks to those who have chimed in for help.
 
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