Another alternator hits the dust and not under warranty

I tend to agree with Lujo.

The original stator design by BWM has proven unreliable over the long haul. BMW has opted not to address by warrenttee for those of us who are "lucky"??? enough to get beyond 36k miles/3 years. BMW does seem to have a cooling fix in the new stator/rotor replacement part for $900...but candidly it too, has not been proven over the long haul in the field yet.

I agree there is no reason at all to think that Ricks or Electro sport replacements are in any way inferior to the original BMW stator, and some reason to believe that they have to attempted to improve their stator performance.

I will be opening up my 3 year old, 30+ k mile F650 (stator has not failed to date) to see how toastie it is. Unless it shows no signs of over heating, I will replace it with either Ricks or Elctrosport...so I can ride this year with more confidence than I could have with the inferior OEM BMW stator in place.

Just waiting for a day above freezing to get in to the garage to check it out.

ps There has been a pretty thorought thread on this topic last year, and several knowledgable people could NOT come up with the epoxy potting that would have significantly higher temp rating....that is why BMW has opted for complex oil throwing mechanical design and the after market guys have tried to reduce the heat generated in the stator

BTW:

Does anyone have one of the old style flywheels laying around they don't need????

I have a stupid idea I'd like to try ... but not with my "real" flywheel ....

I have entertained those same thoughts...

As I mentioned earlier..... I have epoxy that will hold up to 500. F......But no broken stator........ Yet.....

Google search "electrosport stator problems" and you will find more results on their quality.

Now lets here from real world electrosport installs on our BMW F800gs and the mileage they are getting before failure????? Anyone have any miles on Electrosport or Rickys?

The stock BMW stator is actually very high quality but the lack of oil splash or air movement in that compartment has made its life very difficult.

I might have the stock flywheel in my parts bin it would be available for free plus shipping. I got a brand new Electrosport stator in the box and some 500 degree epoxy ready to do what they do not provide. Make me an offer I will ship you the new Electrosport Stator.

I bit the bullet and spent $900 on the new parts and sent the old stator to Custom Rewind for back up.
The Electrosport makes for a great door stop.

PM-ing you now

Ebrabaek:

I like the idea, but how viscous is your epoxy?

Unless it is very low (watery ... and maybe not even then...) it would seem that a vacuum chamber might be needed to get the expoxy in past the first couple layers of windings?

I would guess that after dipping the epoxy would have to be cleaned off the ends of the poles as the I wouldn't think there is enough clearance between the pole tips and the inside of the flywheel to allow it to remain?

I also wonder how much "insulating value" the epoxy adds? Insulation being a bad thing here....

It is great that you have a 500F epoxy....some questions you might want to think about if you have not already

what is it coefficient of expansion over temp? need to be very stable so the stator coils don't loosen up and have vibration failure

what is it's dielectric coefficient? voltage break down, etc

what is it's immunity of oil and oil additives?

how well does it age over time?


the reason I am skeptical there is an adequate epoxy for this environment, if there was BMW would have just changed that and not done the more expensive elaborate mechanical design to facilitate better oil cooling

just my 2 cents

After my F800GS alternator died last Summer while on a trip, my wife started to get paranoid about her F650GS which has virtually the same mileage as mine. So she asked me to open her alternator cover to have a look and this is what I found:

The one on the left (or upper, depending on your screen resolution) is here, and the one on the right, or below, is my failed one.



Hers looks better, for sure. Should I just buy a gasket, close it up and forget about it or should we change it now?

Decisions, decisions. I'd be tempted to close it up and buy a Rick's stator to keep as a spare, just in case.

Emm, it looks almost as bad as yours!! :eek1 Lets change it!

I will be the first to admit.... that I am clueless as to how to dip stators. Have never done it, and perhaps never will . But I do know alot about the epoxy it self, but that hardly makes me an expert on dipping. A few thing do apply, however. Putting the whole stator under a vacuum will not do anything to facilitate more penetrating, as the polymers moves towards the vacuum source, in doing so, it will take the path of least resistance. Only way to get it in really good, is to thin the epoxy. You can do this mechanically, by heating it up, while dipping. I thought it would be fun to experiment, with taking a stator and using the good epoxy, but perhaps as I have no experience with it, I better stay away.....

You could be right about BMW. But I was of the same conclusion early on as a 8GS owner, but have since come to the conclusion, that BMW really don't use the best stuff. The 8GS is full of compromises, that should not have been.
That is just my opinion, but I have lost faith in their support...... Still love the bike though, and will keep it for many moons to come.

Ok guys, we're planning a big trip on our twins and it seems I'm due for an alt failure. Just starting to go thru the 650+ posts so I hope I'm not 205 here.

Research shows RMSTATOR.COM close to me. If you look under "Also Fits" it lists 40+ applications. Could this be true? If so, it'll give you more options when you break down in BF nowhere and you need to McGyver something.

http://www.rmstator.com/en/motorcycle/bmw/f650gs/2009/stator-rm01040

It lists the 650 Single as "Also". Seeing this, I checked my parts pile and found...........






It's from a basket case engine I picked up for free. Measures up ok. Can anyone confirm this will work? If so I've used up all my luck for the week. A 650 single stator should be easy to find used. Like mine hiding in plain sight!

Emmbeedee, RM stator is pretty close to you.........just sayin'.

Very interesting! Coaticook (Quebec) - Might be a good destination for a weekend drive to "La Belle Province"!

Thanks for posting!

Emmbeedee

If mine looks like your wife's...I'll be changing it our for a new one

Yeah, I think you're right. And if it only costs $100, I can buy a dozen for the price on one new style BMW stator. I wish I'd known about the alternatives at the time.

I expect I'll also keep my bike a good long time ...
but I am likewise depressed about my stator, second cracked gas tank, and my burned headlight reflector.
Oh well...

One other question: what is the thermal conductivity of the epoxy ... if it's low then we've "insulated" our stator ... not a good thing.

Many years back I got a tour of a Westinghouse Electric plant where they made small transformers.
All of the transformers,after being wound went through a "potting" station where the transformer was submerged in potting compound and a vacuum pulled on it ... this made the air contained in the windings expand in volume greatly ... when you looked in the view window it appears the potting fluid was boiling, but it was just the air in the transformer windings expanding in volume as the pressure was reduced.

Once some vacuum level was reached (~28" I think...) the vacuum was slowly released and potting fluid got "sucked in" to the windings or pushed in by ambient pressure depending how you look at it....
not sure it would work here, or even it it's a good idea, but it was a really amazing plant tour!

I've got about 7k miles on a ricks stator right now. Keepin an eye on the voltmeter for any drops in charging voltage for a burned phase.

I'm wonder if an ammeter would be a better choice.


Sent from my iPhone

Epoxy is not a good conductor. I was under the impression that the insulation on the wire itself was the baked on shellack. And the epoxy added strength, and stability....... At least the copper coil wires I worked with.... That was the case. But again..... I know nothing about winding a stator.....

Ordered a stator from RM today. Should be here early next week.