Separate names with a comma.
Discussion in 'Airheads' started by 685, Feb 27, 2014.
What's the difference in current draw between the two starters?
According to the sales pitch on EME's website, Valeo starters draw 270 amps, and Bosch starters draw 20% more.
The quality control printout that came with my Valeo clone says it draws 240 amps at 6 nm and it draws 297 amps at maximum power.
I just noticed that the relay EME sells is a 30 amp relay. https://www.euromotoelectrics.com/Relay-BMW-61-31-1-243-207-p/rel-207.htm
The 30 Amp relay drives the starter motors solenoid, the solenoid drives the starter motor. So the solenoid takes the 200+ amps of the starter motor not the relay.
So does the Valeo draw more current than the Bosch? Just trying to understand the need to change the relay.
The Valeo solenoid draws more current than the Bosch solenoid. Thus the relay needs to handle more current for a Valeo system.
The overall draw by the Valeo starter system is less than the Bosh system.
The 'system' comprises, in electrical order (sequential power and time activation wise);
the starter motor
Physically the starter motor and solenoid are combined into one housing.
It is the Valeo solenoid which takes more amps, the actual motor might take less.
I did refer to a factory notice which states that if the Valeo is used with the Bosch relay there is the danger that the contacts will weld together and the starter will be on until you disconnect the battery.
The later bikes which had a Valeo as a standard fitment had a different relay to the Bosch, presumably higher rated and they would seem to be a safe bet, assuming that pin locations are the same as your bike. But if not they are easily swapped.
I found an answer to my question in the Snobum compendium. Snobum's article #15 says:
"BMW has an SI on retrofitting the Valeo starter to certain bikes that came with Bosch starters (1985-1988 bikes). BMW thinks that the old starter relay contacts are not up to the larger current draw of the Valeo solenoid coil. Better contacts and a stiffer spring also helps the contacts to break cleanly. It is my belief that the original relay will usually be OK, but if you want to install one with larger current capacity, and less chance of the contacts welding and the starter running constantly, see this document, which I have here in pdf format for you: https://bmwmotorcycletech.info/Retrofitting Valeo Starter-2383.pdf"
The SI says you need to upgrade the relay when you are retrofitting a Valeo to an '85 - '88 airhead. So it looks like it would be OK to use my stock ('76 R90) starter relay with my new Valeo-type starter.
Not necessarily - read the BMW notice again and check the number of the existing relay, but the new, correct relay is cheap enough and the existing is over 40 years old!
Didn't notice 'welded' relay contacts and rode 'bout 150miles at sixty-five or so; starter spinning along with the engine. Starter survived and continued unfazed. '84 GPz750
First motorcycle "hybrid"?
All well and good Jim, but how far before he had to "Recharge"?
The SI says if you have a starter relay with a diode (it specifically mentions '88 and '89 model year bikes, and relay part number 61311244019), and you want to retrofit a Valeo starter, you should replace your relay with part number 61361391397. It also says: "Only starter relays with diodes are affected. No relay change is required to retrofit the [Valeo] starter to 1977 - 84 R80/100, T, S, RS, or RT models (relays without diode)." I assumed that the relay on my '76 R90/6 would be OK, because it does not have a diode. But I could be very wrong about that: the SI, and Snowbum's comments on it, do not specifically say whether my '76 R90/6 relay will do the job. They don't mention pre-'77 models at all.
So, I still don't know if my relay will handle the Valeo starter. The relay recommended in the SI costs about $100, so I'd like to know if I really need it. I'm hoping one of you has fitted a Valeo starter to a R90/6, and lived to tell about it.
For reference: my stock R90/6 relay is part number 61311357104: https://www.euromotoelectrics.com/product-p/rel-104.htmhttps://www.euromotoelectrics.com/product-p/rel-104.htm. It looks like this:
The relay recommended in the SI is part # 61361391397, which looks like this: https://www.fcpeuro.com/products/bmw-diode-relay-61361391397
^^^ It is an "8 diode relay" according to this seller: https://www.ecstuning.com/b-genuine-bmw-parts/8-diode-relay/61361391397, which may be why it costs $100!
Motobins in England has the --397 relay at a sensible price - EME once had them at a similar price but they no longer seem to have them.
I fitted mine years ago and they were $12- then, didnt realize they were now $100-!
EME lists a ------105 relay for $18.50, Motorworks in England list the same one as being suitable for Valeo equipped bikes - go figure!
These 2 relays are not interchangeable
The SI clearly states that bikes with the DIODE type relay are the only ones effected and yours it not one of them
Your original relay should work just fine if it is in good working order
It would not be a bad idea to replace it with the relay that your bike calls for
"R90/6 relay is part number 61311357104"
If it has never been replaced and you are worried about the contacts welding
During High amp low battery voltage conditions it is common for relay contacts to weld
Here is what is on EME site about the K bike relays
I have seen this many times
Thanks Mrclubike! Seems like you always save my sorry ass whenever I get in over my head with electrical stuff. Speaking of replacing my 44 year old relay, I can get one of these for only a few bucks:
It's a NAPA Echlin AR152. https://www.napaonline.com/en/p/ECHAR152
Is there any reason I can't use it? Here is the schematic for it:
And here is an article from a guy who used one on his stock R90 (presumably with Bosch starter, not a Valeo): http://www.ibmwr.org/original/r-tech/airheads/relay.shtml
I am sure it can be used but depending on exactly what relay you have you may loose the anti restart feature
What numbers are on the original relay
SR9572 or SR9570
The numbers on my relay are SR9572.
I think the SR9570 was used on the /5's and it had the anti restart feature /6 and on didn't so the relay was just a plain relay with junction terminals
I think you will be Okay to use it as long as it gets connected correctly
But i don't think the AR152 is going to be very common like it was in 1995 when the article was written
It was used on late 80's Mopar vehicles
Are you me? Because this sounds exactly like my experiences and response.