BMW R1200RT/R1250RT Forum

Howdy everyone.

I've got an 2007 R1200RT (date on the plate says 0507) and I'm confused about the alternator belt.

Supposedly, a Contitech 4PK582 belt is the correct one, but I ordered a couple and installed one without checking too carefully. Went riding, and it appears the the belt walked off the pulley, got caught behind the crankshaft pulley and damaged the oil seal, as there is oil now in that space.

I looked at the other new belt more carefully and I realized that even though the package stated multi-V belt, the ribs are flat, not V like the oem belt that I took off.

So, annoyed that I didn't check carefully enough, I started looking for a replacement belt. According to the parts fiche, it's supposed to have a belt part # 11 31 8 528 385, but the belt I took off (which, as far as I know was original from the factory - the bike just turned 37000 miles, I bought it with 34000) is part # 12 31 7 690 571 (it's printed on the belt as 12.31-7690 571). It also has printed on it 4 PK 582, which just annoys me more.

I went looking for the belt using both part #s. I found an ebay seller with a BMW OEM belt # 12 31 7 681 841, which they claim is a match for 12 31 7 690 571 and 4PK592.

Wunderlichamerica.com claims that their 4PK592 is the correct fit for my bike, stating that the actual Contitech part # is 4PK592(582).

I'm just trying to find out which belt I should be using so I can get the right one.

TLDR; the belt apparently installed at the factory is 12 31 7 690 571, but the parts fiche says it should be 11 31 8 528 385.

Any help would be appreciated.

Max BMW Parts list # 11 31 8 528 385 for a Hexhead (2007) RT. (Photo from their website).



RealOEM BMW lists the same part # too.

Have a look at this thread, viewtopic.php?t=4305&hilit=4pk+582
The Hexhead and Camhead have the same alternator belt fitted.

What I've been able to find is that the 11 31 8 528 385 is a superseded part number for the original belt.

So I ordered a new belt fro Capital Cycle in Virginia.

What I got was the exact same flat 4PK582 belt.

Here's a picture of the 2 belts. You can see that the old belt has deep V ribs, but the new belt has flat, not so deep ribs. This is a picture of the old belt with the part #. Even Euro Motoelectrics shows the Contitech 4PK582 on their web site (https://www.euromotoelectrics.com/produ ... 582385.htm)

I guess I'm going to call the dealers around here and see what they have in stock. If one of them has it in stock, I'll have to go and compare.

David. wrote: ↑Sun Jun 23, 2024 6:34 pm Max BMW Parts list # 11 31 8 528 385 for a Hexhead (2007) RT. (Photo from their website).



RealOEM BMW lists the same part # too.

Have a look at this thread, viewtopic.php?t=4305&hilit=4pk+582
The Hexhead and Camhead have the same alternator belt fitted.

That's the one I fitted to my 07