Poly V-belt Replacement

[Riff Raff]

I'm due for changing my Poly-V belt. How much difficulty is involved. Also does this require the specialty tools as spec'd in the Clymer Manual or can I do this adequately with standard tools.

 

This is on an R1150RT-P where the exhaust pipes are very near the engine block and just below the belt access cover. Front Paralever prevents pulling straight forward and definitely can't go up. Had it loose and couldn't get cover to slide down and out (any tricks to this)??? Please advise. Don't have a lot of bucks to spend by taking to dealership unless this is the only way. Thanks in advance...

[Sweendog]

I don't know about changing the belt, but getting the front cover off IS possible by the correct sliding around technique. You have to kind of push it upwards and to the left side of the bike to be able to pull the lower, right side corner of the cover out past the pipes. Just keep trying, and you'll eventually see the way it works.

[AndyS]

Getting the front cover off is a REAL pain on RTP's, but once off, cut it in half to make it easy to get back off (and on next time - see attachment.

Changing the belt is easy and no special tools are really needed. Tensioning can be achieved using normal tools so long as you are happy with the 1/4 twis method which has served me well on both the earlier belts and the later ones (which were meant to be set up REAL tight - but I don't).

[Riff Raff]

Too cool! Thank you, very helpful and more clear than what I read in the Clymers manual. I thought I couldn't be as difficult as it sounds, but you never know. I've worked on printing presses and cars for years and love to do my own work, but don't want to take on something I'll just have to put back together and take to BMW dealer.

 

I did not see the attachment re: cutting the cover in 1/2, great idea by the way. Will you please post again or email to me at rbruton@kcbx.net. Very appreciated. -- Riffraff

[StroupDog]

It comes right off if you remove the shark fin, no need to cut it.

[AndyS]

Getting the front cover off is a REAL pain on RTP's, but once off, cut it in half to make it easy to get back off (and on next time - see attachment.

 

here's the attachment - finally

and despite what others say, it REALLY makes a difference to ease of access.

Andy

[Deesdesk]

Hi guys.

New to this website, and new to BMW R1150RT's. I just bought a 2002 last month and I've been getting it ready for the season.

Gone though it and replaced all the fluids (expect the clutch), filters, new battery, and new spark plugs.

Made a horrible mistake and tried to flush the brake system like any other bike I've owned. Sure wish I read up on the ABS system before I started! That required a trip to the dealer to clear and reset my computer.

I just removed the factory speakers and turned my radio compartment into a glovebox with a USB charger, which turns on with the key (picture below)

 

There's 68K on the bike now.

How often should the V-belt be replaced/checked?

[dirtrider]

8 hours ago, Deesdesk said:

Hi guys.

New to this website, and new to BMW R1150RT's. I just bought a 2002 last month and I've been getting it ready for the season.

Gone though it and replaced all the fluids (expect the clutch), filters, new battery, and new spark plugs.

Made a horrible mistake and tried to flush the brake system like any other bike I've owned. Sure wish I read up on the ABS system before I started! That required a trip to the dealer to clear and reset my computer.

I just removed the factory speakers and turned my radio compartment into a glovebox with a USB charger, which turns on with the key (picture below)

 

There's 68K on the bike now.

How often should the V-belt be replaced/checked?

 

Morning Deesdesk

 

You are new here so welcome.  Adding your problem on someone else's thread is called hijacking so we try not to do that here on this web site  as it usually takes the original thread off topic, or can even provide misinformation to future readers. 

 

Seeing as your question is sort of the same engine family & this is an old 2011 thread I will answer your question but in the future please start your own thread on your question or problem.  

 

My latest BMW service bulletin shows a belt replacement at every 36,000 miles.  The BMW service schedule showed 40,000KM (about 25,000 miles).  So take your choice. 

 

On the older BMW boxers time seems to be as bad or even worse than miles as far as rubber products go, if you have no history on when that belt was last replaced then the belt should probably be changed out as preventive. 

 

You can download your BMW  "basic service due info" here__ just scroll down to your motorcycle ___           

 

https://www.ascycles.com/bmw_motorcycle_service_and_maintenance_schedules

 

Just keep in mind that some services might have been changed, or the mileage intervals changed, due to later "service bulletins" sent out to BMW dealers. 

 

Like your brake issue, changing the alternator belt is DIFFERENT than most engines so be sure to read/understand a service manual (or ask here) as the manual specifics a special belt  tensioning tool but there are workarounds. It is fairly easy to strip the alternator adjuster teeth (if the adjuster is over-torqued), or damage the alternator, or damage the wires under the alternator if the new belt tension is set using a pry bar.  

[Deesdesk]

Thanks Dirtrider

My bad, newbie mistake.

I don't do social media, or belong to many of these forums.  I thought that it was frowned upon to start new threads if there were existing threads related to the same subject. In this case R1150RT Vbelts. (so much for good intensions!)

Thanks for the information. I have the "Tupperware" off the bike now, so I will order a new belt and dive in. Watched several you tube videos by licensed BMW mechanics as to how to remove and properly replace the belt. I think I got it; No prybar!

 

Thanks again for the information. As suggested, I will take this conversation to a new thread should I have any further questions/problems on this matter.

 

[dirtrider]

4 hours ago, Deesdesk said:

Thanks Dirtrider

My bad, newbie mistake.

I don't do social media, or belong to many of these forums.  I thought that it was frowned upon to start new threads if there were existing threads related to the same subject. In this case R1150RT Vbelts. (so much for good intensions!)

Thanks for the information. I have the "Tupperware" off the bike now, so I will order a new belt and dive in. Watched several you tube videos by licensed BMW mechanics as to how to remove and properly replace the belt. I think I got it; No prybar!

 

Thanks again for the information. As suggested, I will take this conversation to a new thread should I have any further questions/problems on this matter.

 

Morning  Deesdesk

 

Not sure who you are going to order the belt from but a BMW dealer gets about $40.00 for the belt.

 

Beemer Boneyard (  https://www.beemerboneyard.com/  ) is around $13.00 (plus shipping) but will usually give you a bit of a discount if you mention you belong to this "BMW sport touring" web site.

 

Or, if the writing & numbers are still visible on your current belt then most auto parts stores can match one up for you (some automobiles use the same  4PK6xx belt). My personal preference is a Dayco or Continental brand if possible.  

   

[Jim Moore]

There are also two different alternator belts. Can you read the part number on the belt on your bike?

[dirtrider]

54 minutes ago, Jim Moore said:

There are also two different alternator belts. Can you read the part number on the belt on your bike?

Afternoon Jim 

 

Deesdesk has a 2002 1150RT so that alternator is the 50 amp alternator that doesn't have the factory free-wheeling pulley on it, that also means  it should have the  4PK611 poly-V belt on it now.

 

It should be a 4PK6xx belt so as long as he gets the same  length  4PK6xx (should be a 4 rib 611mm long) length belt then it should fit properly.

[Deesdesk]

Tired of doing office stuff today, so off to my mancave!

Its a BMW/Continental 4PK 611 SR belt.

It actually looks to be in good shape, no cracks or wear. I suspect it was the original belt and needs replacement regardless.

Before I removed it I took note of the tension on the belt, it seemed pretty taunt.

I watched this service video by a guy named Chris Harris. He said that the tension adjuster bolt should only have 8Nm pressure it and the locking nut (in front) should be torqued to 20Nm.

(He also said the cover plate could not be removed on the left side, but it actually came out without any trouble)

I can tell you that the nuts and bolts had way more pressure on them when I loosened them then 20Nm (14.75 ft-lbs). 

Does anyone know if those torque specs are correct?

 

 

[9Mary7]

Chris's torque specs are correct.

[dirtrider]

Quote

 

Its a BMW/Continental 4PK 611 SR belt.

It actually looks to be in good shape, no cracks or wear. I suspect it was the original belt and needs replacement regardless.

Before I removed it I took note of the tension on the belt, it seemed pretty taunt.

I watched this service video by a guy named Chris Harris. He said that the tension adjuster bolt should only have 8Nm pressure it and the locking nut (in front) should be torqued to 20Nm.

(He also said the cover plate could not be removed on the left side, but it actually came out without any trouble)

I can tell you that the nuts and bolts had way more pressure on them when I loosened them then 20Nm (14.75 ft-lbs). 

Does anyone know if those torque specs are correct?

 

Afternoon Deesdesk

 

Be careful in what video's you watch as some are off base a little. 

 

SPECIFICATION  is 8nm on the adjuster & 20nm on the nut-- BUT! that is not always correct.

 

8nm on the adjuster can leave the belt slightly loose (especially on a new belt), I have done many so have a  good "feel" for how tight the belt should be. I usually initially set the belt using a nice firm 1/4 twist  at the middle of the belt run. (too loose & you will easily be able to twist the belt to, or past, 1/4 twist / too tight & you will need pretty good pressure to get it to 1/4 twist mid run).

 

Try the 8nm then see where you are at (twist wise), if you use the 8nm as gospel then you should re-check the belt tightness at about 1000-2000 miles of riding as they usually stretch a little.  If 8nm doesn't get you a nice firm 1/4 twist then add a little.

 

On your belt looking good-- they usually do look good in just casually inspecting.  Turn the belt inside out then fold it back to have tight radius ends. You will usually find small cracking on/across the ribs on older belts.  

 

 

 

[Deesdesk]

Thanks You Both,

Good advise, I just need to find a new belt and then we're off to the races (metaphorically speaking).

I got all the equivalent belt numbers, none locally. I'll order one on line.

[dirtrider]

4 minutes ago, Deesdesk said:

Thanks You Both,

Good advise, I just need to find a new belt and then we're off to the races (metaphorically speaking).

I got all the equivalent belt numbers, none locally. I'll order one on line.

Afternoon Deesdesk

 

As a rule if a local (major) auto parts store has it in their system they can usually have it to your local store in one day. 

 

I buy special (seldom stocked) spark plugs from my local Auto Zone, if I make the order early in the morning they will usually have them that afternoon or by noon the next day.  

[Jim Moore]

Btw, there's nothing wrong with using a pry bar to lift the alternator into place. Just make sure you're aware of the location of the HES wires.

[Deesdesk]

The belt finally came in. I went with a Gates K040233. It's a snug fit, as it is only 23.3 inches. The Dayco 5040240 is actually 24.5 inches and I didn't feel there was enough adjustment room to take up the slack. The belt that came off it was almost to the top of the adjustment slot. Yes, I understand that that was likely due to it stretching over time and people adjusting tension. However that only occurred to me after I ordered the Gates belt.

Back to the topic at hand - Installing the belt.

I put it on and started to adjust the tension at 8nm.  That did not even begin to give me enough tension. I could flex the belt well past a 1/2 turn point with minimal effort at 8nm. So, I kept going until I got to the point of having a good 1/4 turn in the middle of the belt with some effort to do so. No sure exactly where I ended up as far as torque goes. But by using the "1/4 turn with moderate effort" I feel I got it right. It also feels similar to the tension I've used on other serpentine belts.

Torqued down the the other nuts and checked that the belt is stilling properly on the pullies. 

 

However, with my engineering background, I still 'feel' as though I've done something wrong by not adhering to the spec's.

 

[Paddler]

I ordered a Continental belt through Auto Zone on Friday.  It's not the 4PK611, but rather a 404245, which sounds like it's .5" longer.  They don't show the other part number, but cross referenced it to a Duralast belt that's 24", I think it's a 240K4.  My question is which is preferable.  My original belt is 11 28 1 341 779.  1998 R1100R.

[dirtrider]

23 minutes ago, Paddler said:

I ordered a Continental belt through Auto Zone on Friday.  It's not the 4PK611, but rather a 404245, which sounds like it's .5" longer.  They don't show the other part number, but cross referenced it to a Duralast belt that's 24", I think it's a 240K4.  My question is which is preferable.  My original belt is 11 28 1 341 779.  1998 R1100R.

Afternoon Paddler

 

I don't know as those numbers don't perfectly correlate to a 4PK 611.

 

The 4PK 611 is 611 millimeters (about 24") , so if that belt is about 24", has 4 ribs, the rib spacing is correct, & the belt width is correct then it should work.

 

 

[Paddler]

Thanks, DR.  The Duralast is 24", 611mm is 24.05", so close enough.  I don't know the country of origin of the Duralast, as it's Autozone's proprietary brand and may not be of the same quality as the Continental.  I also don't understand why Continental uses two different types of part numbers.  Weird.

[Deesdesk]

All the manufacturers that I researched (Gates, Dayco, ACDelco) used lengths that were + or - 24" but none of them measured exactly 24" (611mm).  As DR suggested, as along as you're within a 1/2" of the 24" and the belt has the 4 ribs you should be fine. DO NOT use the Elast belts. They are for systems that use belt tensioners to take up any slack.

Sounds like you're good to go.

Let us know how you make out on the installation. 

 

[Paddler]

When I went down to Autozone I took the OEM belt with me.  It looked like the Continental belt was a bit longer, so I wasn't sure I could achieve proper tension.  But they had also brought in the Duralast belt, which is the Dayco belt in a Duralast sleeve.  It's a 4PK610, so perfect.  And, it was $7.99, a third the price of the BMW.  Installation was easy, although my torque wrench only goes down to 16.9NM.  I had to extrapolate, but the tension feels right and it doesn't squeal on startup.  Easy peasy.  Planning a tour to northern California soon, the bike is ready to go.  Thanks, all.  Very helpful.:)