Alternator Belt Replacement

[tobes]

Has anyone replaced their alternator belt? I just did my 30k service and now need to change the alt belt. I know there is a special tool BMW sells for this but the Jim VonBaden method of spinning the pulley with a large wrench looks pretty easy. He did this on a GSA though, so I'm wondering if there would be any more difficulty on our R1200R. Thanks!

[ContraMoto]

I did the replacement on a 12GS. Looking at the R, I can't imagine it would be any different. Simple enough job for a wintry day...

[tobes]

What method did you use to get the new belt on? I tried both JVB methods: holding the new belt while bumping the rear tire & using a large wrench to spin the bottom pulley. Problem with the R1200R is that the oil cooler is in the way being right in front of the belt. Tough to get a wrench in there. Holding the belt didn't work either. Think I'm going to need to get another pair of hands to help with this.

[tobes]

It took three people, one bumping the rear wheel, and two holding the belt onto the pulley, but the alt belt is now on. That was a PITA. The old belt looked fine at 31K. Getting the plastic alt belt cover off was a PITA too. Had to pull the oil cooler out as far as possible by unfastening the metal hose from the engine, turn the handlebars to the right, then pull the cover all the way down and out from under the bike. Good for another 30K.

[tobes]

No good video of the belt install but here is a short clip of the belt cover install. Removal would just be the opposite.

http://www.youtube.com/watch?v=fAC7f-S0pDo

Here is a photo of the old alternator belt being removed using a cut up Coke can.


R1200R Alternator Belt by mikeburawski, on Flickr

[deilenberger]

The hardest part of doing the belt is removing the cover over it. Take the two screws that hold the oil cooler in place out and let it dangle off the hoses. After removing the screws for the cover, you can just about wiggle it around and down the opening in the telelever leg. This is much easier IF once you get it off you throw away the foam insulating insert in it (BMW discontinued using this on later models since it trapped water behind it and caused bubbling of the paint on the front engine cover - it's there for sound insulation, not a huge concern for most of us..)

I then used a cut-up plastic Coke bottle to slip under the bottom of the bottom pully as I turned it using the crankshaft nut. Once the plastic was between the pully and belt - the belt just slid right out. Installation was about the opposite, I used the plastic to walk the new one on as I rotated the engine with the big nut.

If you only have 30k miles on your bike, you're not "due" for another 6k.. and in reality - the belts seem to last about forever now - they're elastic so there isn't a problem with under or over-tightening them and people have reported changing them at 60,000 miles and having them look just fine. I did mine at 36k miles because the service schedule said to - next time I will be more like 42 or 50k miles. I kept the perfect one that came off as a spare.

BTW - while it took a while to figure out how to wiggle it out - NOTHING was disconnected to remove the plastic cover on my bike. The big trick part was the inner foam crap hanging up as I was moving the cover around. I seem to recall keeping it IN the cover was the hot setup..

On a scale of 1-10 wrenchs, this one is no worse then a 3..

[Lost Rider]

If you only have 30k miles on your bike, you're not "due" for another 6k.. and in reality - the belts seem to last about forever now - they're elastic so there isn't a problem with under or over-tightening them and people have reported changing them at 60,000 miles and having them look just fine. I did mine at 36k miles because the service schedule said to - next time I will be more like 42 or 50k miles. I kept the perfect one that came off as a spare.

I still have the original belt on at 63,000 miles... and carry a spare.
I'll change it when it breaks, but this is all great info to have for that time.

cheers

[ContraMoto]

Good tip above about pulling out the foam block and tossing it. It holds moisture and dribbles it out onto the case cover for days and days after it gets wet. Corrosion and chipping paint inevitably results.

This job is also easier without the plastic scoop thingy around the oil cooler. I pulled that off and tossed it in the box that also holds the carbon canister, the wings from the sides of the forks and the reflectors from the sides of the forks. Naked bikes like to be naked.

Come summertime (ie, the no-rain season), the front fender also goes in that box.

[tinytrains]

Here you go:

http://www.youtube.com/watch?v=YzPTPN98x40

The Guy uses a crescent wrench to slip it right on.

Scott

[tobes]

I believe that is a GS. I tried that method and ran into a problem with the oil cooler being in the way of the wrench. In searching MOA & ADV it seems riders have experienced varying degrees of difficulty and come up with different methods to get the belt on: guiding the belt with a palm while bumping the rear wheel, using a wrench, using a punch or shim to guide the belt, and getting the BMW tool.

[deilenberger]

Uhhh.. Mike,

Drop the oil cooler. It's two bolts, leave it hanging by the hoses (they can take it for the time it takes to change the belt).. then you have all the space in the world to get a big-ass-socket on there or a large adjustable wrench (I have the socket - bought for a swing-arm nut on an airhead a few decades ago..)

[tobes]

Thanks for the tips. A socket would have been the way to go. What size socket is that? I'd like to get one for next time. I swear I dropped the oil cooler and tried rotating the engine with a large crescent wrench, couldn't get it that way. But this is why I'm not a mechanic. Hopefully this info will be helpful for someone else planning this job.

[yim4]

I was able to replace the belt pretty easily with the pin punch method that is described on advrider.com. Essentially you stick a pin punch or something similar in a hole to keep the pulley from walking off the lower pulley, while you rotate the crank with your wrench. The belt pops right on.

There's a more detailed thread somewhere on the site but here is what I am talking about:
http://www.advrider.com/forums/showthread.php?t=494249

I also dropped the oiler cooler per the BMW repair dvd and everything was accessible to rotate the crank/etc.

[R12RnHouston]

My turn to change the generator belt today. Got the cover and old belt off with no problem and dealt with the corrosion that had accumulated behind that bloody foam plug.

Read recently that the new 592 is a PITA so I was all set for a struggle installing it, but did a little more poking around and came across this post that mentions the “pin punch method” which I followed over to ADV (http://www.advrider.com/forums/showthread.php?t=494249) for a little more detail. So, I also gave it a try with a 5/32” punch and a big crescent wrench and the belt was on in about 45 seconds! Yes indeed it's easy peasy!