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Over on the ADV Riders Forum there's like 54 pages of discussion on F stators over heating and burning up. Is this that bad a problem? From the photos on the thread, it appears the flywheel has been altered to furnish better oil flow & cooling to the stator. Anybody have any idea which models and years incorporated these modified flywheel/stator assembly?

We've got this guy in our local BMW Club that just seems to relish putting out anything negative about Beamers. I'd like to counter him.

Thanks,
Mike
 
Early stators burn up. BMW sold only whole alternators at about $1,000 a pop but didn't sell just replacement stators because apparently the new alternators (the rotors) had been revised or so I heard on the internet. Aftermarket stators are available from Rick's and others for $155. I installed a Rick's stator and it has lasted about 30,000 miles so far. Since I can do 6 aftermarket stators for the price of one BMW OEM alternator I'll probably wind up ahead. I am not big on spending $1,000 for replacement parts that were defective in design from the get-go, even if they do barely outlast the warranty. No ammo for you for your club member here!
 
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Thanks for your comments, Paul. Always good to get your input. You say "early stators fail". That's my point, has BMW revised the stators to correct the problem? Comparison photos show replacement flywheels with half moon slots in them. (sorry being an old cogger, I'm light on computer skills and can't post the photos). Seems to me BMW's problem isn't correcting problems, it's not admitting there is a problem and announcing the correction. Guess I'll have to pull the side case on the next oil change to find out if my F700GS has the "improved" flywheel/stator.
The 700 is still the best motorcycle I've had in my 42 years of biking.

Mike
 
I have a 2010 F650GS and have lived thru all this.

The early F800s have retrospectively, poorly designed rotor/stator design. It is an oil cooled design...the original rotor did not fling enough oil to cool the stator. The stator overheated and "coked" /burn/ toasted the oil on the stator...this effectively thermally insulate the stator more...so eventually it overheated and fails.

The BMW fix is a redesign rotor which flings the oil "better" so there is better cooling. About $1000 for this fix.

I too went the cheaper route and at 20,000 miles I preemptively (before a trip to alaska) replaced my Stock stator (yes coking was present but it had not yet failed) with an Electrosport after market one
.
I also went to full synthetic oil, on the premise that it will endure high temperatures better than standard oil.

I have over 45,000 miles now with out failure....but if I open the stator up...I expect i will see over heated oil residue.

If it was to do a long trip..id replace it with a Rick's or Electro sport after market stator...$200 and about 1 hr work.

I think the 2013 F800 model have the new rotor...I'm sure some one else on this list have the fact on the true date.
 
Here is a simple summary of the replacement. I'm sure if you search the web you will find a more detailed one.

Remove the stator case cover....about 10 bolts.

break gasket seal...try not to damage gasket or have a new one.

Slide case straight out....note strong magnets are involves so you will feel that.

Unplug stator from Regulator.

You will see the stator bolted to the case. Likely see cokeing as well. remove bolts and stator.

Bolt in new stator

replace gasket..have a tube of gasket seal..apply some especially around the grommet where the wires come thru the case.

The strong magnet makes placing the case properly with out moving the gasket a bit tricky.

Bolt up the side case.

Plug in the new stator to the Regulator. Electro sport coms with the right plug on the wires....with Rick's you have to splice the wires.

you are done
 
Your 700GS should be just fine. I believe that the redesigned stator came out prior to that model's release.
My '09 GS ate its rotor early last summer, at about 35K miles. My local dealer helped me get coverage from BMW on the replacement parts, which were the new redesigned items, even tho my bike was out of warranty.
I was happily surprised to get that resolution; I did not expect it at all.
 
Your 700GS should be just fine. I believe that the redesigned stator came out prior to that model's release.
My '09 GS ate its rotor early last summer, at about 35K miles. My local dealer helped me get coverage from BMW on the replacement parts, which were the new redesigned items, even tho my bike was out of warranty.
I was happily surprised to get that resolution; I did not expect it at all.
By "ate it's rotor", could you elaborate? I was thinking they just stopped working. I sorts thought it was the stators that were going bad...Here is the one, from Ricks for my F800gs-
T_21-023.jpg

And, again from Rick's, "How to test a stator".
https://www.youtube.com/watch?v=5v2LtHlvcqI
I am curious as maybe I have this to look forward to?
OM
 
By "ate it's rotor", could you elaborate? I was thinking they just stopped working. I sorts thought it was the stators that were going bad...Here is the one, from Ricks for my F800gs-
T_21-023.jpg

And, again from Rick's, "How to test a stator".
https://www.youtube.com/watch?v=5v2LtHlvcqI
I am curious as maybe I have this to look forward to?
OM

my bad. should have been stated that my stator up and died, not the rotor.

Again- the original stator had insufficient oil (and air) distribution, due to too few open passages. New stator resolved that design issue.
 
my bad. should have been stated that my stator up and died, not the rotor.

Again- the original stator had insufficient oil (and air) distribution, due to too few open passages. New stator resolved that design issue.
Yeah, no problemo wus just wondering ;) I think I ran through the ADV thread a while back and some guy rewound his own :eek That's hardcore.
When I get time I hope to put together a sticky with some of the F-Twin wisdom, this will be a good one to include.
OM
 
Stator overheating on the pre-2013 F bikes can be mitigated somewhat by replacing the OEM shunt type regulator with a series type. I have opted for the Shindegen SH775 regulator. It has a different form factor that the OEM (which is unique) so some minor fabrication is required as well as some assembly of connectors to adapt the Furukawa connectors on the regulator to the BMW harness. FWIW here is a photo of the SH775 and the aluminum plate I fabricated to adapt it to the existing bracket on the GS so as to move it up and over such that the connectors and wires are well away from the sprocket cover.

SH775 Bracket.jpg

And here it is installed.

SH775 with cover 1.jpg
 
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It’s good to see helpful posting in F-Twins. :thumb

One of the suggestions (ADV thread) suggested that the owner may try to machine extra holes in the rotor. Fairly sure that they are balanced, probably difficult to do without a specific machine that I don’t have access to.
OM
 
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