2004 R1150 GS Alternator Pulley Belt

[coach785]

I am looking at putting the pulley belt my self. Does any one have any Suggestions.
Thanks
Fro the help

[BubbaZanetti]

just did this on my S last week for the first time.

pretty straight forward after you get the tank off or sufficiently moved back. loosen the three bolts, move the alternator down, remove the belt, put the new one on and move the alternator back into position, checking tension on the belt. i couldn't get the alternator to move up "the proper way" (using the pivot bolt on the left with properly set torque wrench) so i just levered the alternator up from underneath using a screwdriver. 1/4" defelection or the ability to turn the belt 90 degrees when properly tensioned is what you're looking for.

i'm not sure, but your 04 might use a slightly different belt than my 99.

[glwestcott]

Just helped another guy do his 1150 GS alternator belt. You don't need to remove the tank. You can take the cover off from the front and reach all three bolts with wrenches. Can't get a torque on the top one, but you can on the others and just do the top one with a box wrench. Prying up with a large screwdriver until the belt will only twist 90 degrees give you appropriate tension. There is a cable there, but very easy to see and to avoid. All in all its a short and easy job. I have done my 1100 RT the same way and no problem with slipping or squealing belt. Charges fine. Think about a car alternator, if you have ever done one of those, prying up until the tension feels about right is just what you do - torque wrench and special tool - me thinks that is nice, but really just a bit of money you don't need to spend.

[coach785]

Thanks I will give it a try

[GlobalRider]

Have a look at these FREE downloadable 1150 Service Videos (http://www.advrider.com/forums/showthread.php?t=143063&highlight=service+videos).

See the second post.

[AntonLargiader]

Hopefully you haven't started yet. The alternator belt on your bike should be an ELAST type which doesn't get tensioned conventionally. There's a tool at the dealer for setting the distance between the pulleys. Most people find that they can walk the old belt off and walk the new belt on without moving the alternator. If you have loosened the mounting bolts, you will not get the correct tension without the BMW tool or something that provies the same result.

[GlobalRider]

If you have loosened the mounting bolts, you will not get the correct tension without the BMW tool or something that provides the same result.

Anton, I haven't had the need to look at mine yet, but OMG, why do they overcomplicate things unnecessarily. Its an alternator belt, not a timing belt.

[AntonLargiader]

...why do they overcomplicate things unnecessarily. Its an alternator belt, not a timing belt.
It's simpler than it was; you just need to know that you have that system and not the old system. No question about how much tension is correct. The complication is that they use the parts from the old system so someone who is looking for them will not necessarily know. And people assume things all the time. BMW never said to adjust that belt with the tensioner.

I wish my bikes had the ELAST belt. Much easier.

[coach785]

Where can I get the special tool from

[GlobalRider]

It's simpler than it was; you just need to know that you have that system and not the old system.

So what are the differences (are pulleys different and is the belt different) and when did they implement them? Did they switch over partway through a model range?



No question about how much tension is correct. The complication is that they use the parts from the old system so someone who is looking for them will not necessarily know.

Well adjusting tension according to the BMW Service Manual is a no-brainer. Apply 8 N.m. torque to the tension adjusting bolt.

I'm not clear on your other sentence. Owners are using parts with the old system with parts of the new system?


BMW never said to adjust that belt with the tensioner.

The BMW Service Manual CD that I have does. Is there a Service Bulletin out and if so, does someone have it in PDF?


I wish my bikes had the ELAST belt. Much easier.

So what exactly IS an ELAST belt and how does it differ from the previous design used?

[glwestcott]

Hopefully you haven't started yet. The alternator belt on your bike should be an ELAST type which doesn't get tensioned conventionally. There's a tool at the dealer for setting the distance between the pulleys. Most people find that they can walk the old belt off and walk the new belt on without moving the alternator. If you have loosened the mounting bolts, you will not get the correct tension without the BMW tool or something that provies the same result.

Anton, again I disagree with the need for the tool. The Elast belt is simply a belt that is made out of material that lasts longer. You can easily get the right tension by using a large screwdriver. The tool is nice and you can get it from your dealer, but there is no need for it. You can do a simple pry, in my case with a large old screwdriver, by twisting the screwdriver until the belt is tight enough that you can turn it about 90 degrees, but no more. If you fire it up and there is no squeal and the charge light goes out, your in business. You would really have to torque on there to get it tight enough to damage the belt. There really isn't any problem prying to set the tension any more than there would be with a car.

[coach785]

about how often do I need to change the belt? I know BMW say's every 36000 can it go longer.

[AntonLargiader]

Sounds like a good topic for a tech article.

As for the 90 degree test, pardon my french but it's total crap. People who don't know what tension they are actually looking for can convince themselves that just about any tension will seem to get tighter at 90 degrees. I've seen it on other types of belts as well. Does any manufacturer specify a 90 degree twist as a method of establishing correct belt tension? I mean, Chang Jiang might if they used a flat belt, but how about a mainstream producer of cars and motorcycles?

All is OK as long as the belt doesn't squeal and the charge light goes out? I'm not even going to go there.

[glwestcott]

Sounds like a good topic for a tech article.

As for the 90 degree test, pardon my french but it's total crap. People who don't know what tension they are actually looking for can convince themselves that just about any tension will seem to get tighter at 90 degrees. I've seen it on other types of belts as well. Does any manufacturer specify a 90 degree twist as a method of establishing correct belt tension? I mean, Chang Jiang might if they used a flat belt, but how about a mainstream producer of cars and motorcycles?

All is OK as long as the belt doesn't squeal and the charge light goes out? I'm not even going to go there.

Good grief! Ok, here's a response from personal history so we can "go there."

I have a 34 foot sailboat that has a high output alternator that I installed prior to sailing it to Hawaii. It was the only way we had to replace electricity used on the trip. The higher output alternator than the one that came standard for the boat was sized to be the maximum size I could use without slipping the belt when she was really being drawn on. Guess what, no torque wrench to set it. Two weeks over and three weeks back, depending all the way on that alternator and belt combination and no problems. Several years later and the belt is still doing its job.

Many, many cars and several bikes later and I have never used a set torque on any of the machines to set alternator belt tension. Guess what, never had a problem with any of the belts dying prematurely, bmw included. I suspect that the strain on the belt on my boat, given the switch to a much higher output alternator with same old drive pulley, is much more stressful on the belt than what is happening on my bmw.

I still believe that changing an alternator belt on a bmw is simple, easy, and there is no downside to not purchasing a special tool to get belt tension exactly right. I have almost 74,000 miles on my R1100RT and when I changed the belt out at 72,000 miles, I could see no discernable wear. I carry the belt as a spare just in case in my toolkit. By the way, the belt was also changed at 36,000 miles by prying, not using a special tool and torque wrench.

[BubbaZanetti]

I still believe that changing an alternator belt on a bmw is simple, easy, and there is no downside to not purchasing a special tool to get belt tension exactly right. I have almost 74,000 miles on my R1100RT and when I changed the belt out at 72,000 miles, I could see no discernable wear. I carry the belt as a spare just in case in my toolkit. By the way, the belt was also changed at 36,000 miles by prying, not using a special tool and torque wrench.

i think what anton was aluding to was the possiblity of damaging the internals of the alternator. stress on the bearings, etc, is going to increase with excess pressure from the belt if it is over torqued. you have probably been lucky and had a good feel for how the belt should be set. if you were to just pry up on the alternator as hard as possible, and tighten it down, i bet alternator failure would occur pretty quickly, regarless of belt condition.

but that's just my own conclusions:laugh

[AntonLargiader]

GL, I'm glad what you did worked for you. I've done some ocean sailing and having electricity available sure makes things a bit easier.

However, none of what you wrote is relevant to my comments and this this discussion, which are about the ELAST belt (which is not just a longer lasting belt) and the ability of an inexperienced person to gauge proper belt tension by someone else's description a 90 degree twist or similar means.

If someone wants to tighten their ELAST belt based on how you tightened a different kind of belt, that's up to him. I'm just presenting the information that I know.

[glwestcott]

Antoine - consider this. There is no optimum torque for tightening belts. There is a range of acceptable torques from too loose where the belt slips, i.e. squeals, to too tight, where it is so tight it may damage the alternator shaft or shorten the life of the belt. The manufacturer's listed torque to tighten is likely simply the mid-point of that range. The question is can one get not to the exact recommended torque, but within the acceptable range by hand. Since the range is defined as from too loose, i.e. slip - which can be identified by squeal, to too tight, which can be guarded against by insuring the belt can be deflected to some degree, but not enought to lead to squeal, I think it can easily be reached by hand.

As to the ELAST itself, it was introduced as a belt that allowed longer intervals between changes based most likely on mean time to failure stats. I would bet that the reason it can extend these intervals over the PolyV belt is that it is more durable, i.e. stronger, less degradation under heat, etc.

If those two things are true, then I think the tool is superfluous and we can happily avoid spending our too hard to come by and keep bucks.:nod

[AntonLargiader]

As to the ELAST itself, it was introduced as a belt that allowed longer intervals between changes based most likely on mean time to failure stats.
Hey, maybe you should be writing the article instead! What was it extended from, and what was it extended to?
:lurk

[jdiaz]

i think what anton was aluding to was the possiblity of damaging the internals of the alternator. stress on the bearings, etc, is going to increase with excess pressure from the belt if it is over torqued. you have probably been lucky and had a good feel for how the belt should be set. if you were to just pry up on the alternator as hard as possible, and tighten it down, i bet alternator failure would occur pretty quickly, regarless of belt condition.


Actually, a guy on IBMWR used to tighten the alternator belt on his R1100RSL way beyond normal spec, because he felt the bike ran smoother over 5K rpm. He put over 110K miles on that bike without an alternator problem, although he changed belts more frequently than most folks.

[coach785]

Well I tried t put the pulley belt on and broke the bolt that the special tool fits on.
I can see on the other side of the bolt there is a hex head can I take the broken bolt out the way or do I have to drill it out Or do I need to take it to a dealer.

[AntonLargiader]

Bolt that what special tool fits on? Are you still listening to the people telling you to tension this the old way?

[coach785]

So How Do I Fix My Problem Drill It Out Or Scrwe It Out

[gsinmaine]

Try to scrwe it out if not drill slow w/lefthand bit Or 5lb fff black powder 2ft fuse an run like hell

[AntonLargiader]

You should be able to remove the broken bolt from the back, but I can't see the specifics of your situation.

However, provided your bike didn't have a defective bolt, you could experience the same thing if you reattempt whatever it was that you did to break the bolt. Exactly what were you trying to do, using what specifications, and at what point did things go wrong?

[coach785]

I was using the special tool and over torque the bolt



8820

[AntonLargiader]

Well, as I explained before, that's the wrong procedure for your bike. If you feel like actually solving the problem, I think visiting a dealer is your best option; either for them to do the work or for you to borrow/buy the correct tool.

[AntonLargiader]

Just to clarify things, can you give us some more info? What is the production date of your bike (should be on the frame sticker near the steering head, showing month and year) and what is the part number of the belt you have? Also, does your upper alternator pulley have a finely splined inner ring and a part number ending in 716?

[coach785]

2004 R1150 Gs
On The Frame O3/03. Part # 12317681841

[AntonLargiader]

That's not an '04. Maybe it was titled in '04 but it's an '03. That changes a LOT.

[coach785]

So what does that change?

[AntonLargiader]

Also, does your upper alternator pulley have a finely splined inner ring and a part number ending in 716?
Let's get all of the information at once, OK?

[veva71]

Hi all. I `m 5,7 And I want to get this bike from a friend. Of course is to tall for me.
Any way to lower it a couple ",seat,shock etc.
Is it a good year, any bad experience w/it?. I`m selling my 03 650 gs.
Thanks Mario

[bikerfish1100]

Hi all. I `m 5,7 And I want to get this bike from a friend. Of course is to tall for me.
Any way to lower it a couple ",seat,shock etc.
Is it a good year, any bad experience w/it?. I`m selling my 03 650 gs.
Thanks Mario

mario- if you want your questions answered, here's a few suggestions:
1) learn to use the search function. these type of questions (lowering a GS?, good year/concerns?) have been asked a gazillion times, and the answers haven't changed any.
2) if you have a new question, don't piggyback onto a barely related thread- start your own.
3) if you do # 2, you will likely get a few answers that sound just like my answer #1, along with direct answers from a bunch of guys who love repeating themselves from the last time someone asked the same questions becuasetehy love telling people about what they've done to make their perfect bike perfect for them, and you should love it too!

[PETDOC]

[QUOTE=GlobalRider;203114]So what are the differences (are pulleys different and is the belt different) and when did they implement them? Did they switch over partway through a model range?

Pulley and belt are different. BMW switched the belt/pulley mid cycle on the '04 1150 GS. If your bike was made before July 2003 it has the older belt and pulley. After 7/03 new Elast belt and pully.