98 R1100RS Rattling Noises

[waehrik]

Hello all,

(skip this paragraph if you don't want to read my intro )
I'm new here as I just got an R1100RS over the winter and I've put about 3k on it so far (I live in NH so not much opportunity to ride until spring hits). I got it in trade from a dealership and thought I lucked out because the bike I was trading in (00 CBR1100XX) had a much higher book value but I didn't like the bike and wanted something more comfortable and suitable for touring. Hence the R1100RS with luggage and a back rack. The dealership jumped at an even trade and I rode home with the BMW. It didn't run very well on the hour ride home, but it was also 20 degrees out so I figured that made sense, plus I had no idea how long the bike was at the dealership for. I parked it and started it up again a couple months later and found it still ran very poorly. I had paperwork from the dealership showing a Level II service being done just 2k ago, but I tore into it just to make sure everything was done right. I found the TBs were out of synch, valves were out of adjustment, and the TPS was way off. It ran much better afterwards. I had a Holeshot slip on from my old Bandit 600 and after I realized the BMW had a standard 2" exhaust I had a friend at a muffler shop make me up a midpipe and the Holeshot pipe went on easily. I pulled the CCP since the o2 sensor was removed. It was running a little lean with a high idle (1500rpm) regardless of the BBS position so I moved the throttle plate stop screws to stabilize the idle and reset the TPS to 0.400v at that point. With the silencer in the pipe to give some back pressure (it is essentially a wide open smooth pipe otherwise and LOUD) the mixture is almost right on. I have very slight surging around 3500rpm but can live with that. The bike runs very well.

Except for this extremely annoying rattling noise. It sounds like a bag of marbles or someone jingling their keys quickly and only occurs when I'm briskly accelerating or engine braking. I don't have any noise at idle (since I replaced the left side cam chain tensioner with the updated version) and the rattling will fall off if I pull the clutch in. If I park the bike on the center stand in neutral and rev the engine it'll make the noise as it spins back down to idle, so I didn't think it was anything to do with the transmission. I'm extremely confused by the noise and it's very annoying. I've tried searching around and the CCT seems to be the source of the noise for many people but I've already fixed that. And the throttle butterfly shafts are not vibrating, I've held onto the pulley on both sides and the noise did not diminish. With 28k on the bike I wouldn't think anything would be worn out. Does anyone have any thoughts what it might be or what I could check next?

 

[Picinisco]

I'm new here as I just got an R1100RS over the winter and I've put about 3k on it so far......Except for this extremely annoying rattling noise. It sounds like a bag of marbles or someone jingling their keys quickly and only occurs when I'm briskly accelerating or engine braking.

Use the next grade higher gas.

 

[waehrik]

Use the next grade higher gas.

I'm running 91 right now (the highest out here in the Boston area) but I can try adding a bottle of octane booster to try that theory. Do you think it's pinging from detonation? I've never heard it before and the youtube videos seem widely varying on the subject.

 

[Picinisco]

I'm running 91 right now (the highest out here in the Boston area) but I can try adding a bottle of octane booster to try that theory. Do you think it's pinging from detonation? I've never heard it before and the youtube videos seem widely varying on the subject.

Mine pings on 87. It is good on 91. If I forget and put in 87 I add some octane booster to take care of it.

Try the easiest solution first.

Cheers....John

 

[waehrik]

Mine pings on 87. It is good on 91. If I forget and put in 87 I add some octane booster to take care of it.

Try the easiest solution first.

Cheers....John

I'll give it a shot next time I'm out riding (Thursday). On the way home from work today I tried something completely different and replaced the intake air temp sensor (IAT) with a 30k ohm resistor to try and get the engine to richen up the mixture. If the noise is from pinging from running lean that should have fixed it. It did seem to be a little better but that could have been a placebo effect. Plus I was stuck in traffic so there wasn't as much room to really test it.
I checked the range of the stock IAT sensor and it ranged from 1.8k ohm at 98 degrees (and humid, yuck!) to 7.8k ohm after sitting in my freezer for half an hour at 30 degrees. So the 30k is making the bike see very cold and dense air was my thought. It's kind of like what the Accelerator Plug and BoosterPlug do, and the idea was courtesy of a thread here.
Of course that's all only relevant if I am simply running lean and there isn't something else doing the rattling. I pulled my plugs and the insulators were white but no flecks of metal or anything like that. I'm getting about 210 miles per tank, I'd think it would be higher if I were running very lean. Plus there isn't any stumble during acceleration.

 

[Picinisco]

You certainly seem to know a lot about what you are doing so it makes my feeble contribution seem lame. But you never know.

I have been chasing an annoying vibration for the past year and feel that I may have finally found it. Of course I have synced and valve adjusted the thing to death and today took the aftermarket trunk off the back. No vibration today but along with the aftermarket trunk I adjusted the valves one more time. So either I finally got the clearances right or this trunk bounces about at a very high frequency. I suppose I could put the trunk back on and see once and for all but I do not want to tempt the gods.

John

 

[waehrik]

You certainly seem to know a lot about what you are doing so it makes my feeble contribution seem lame. But you never know.

I have been chasing an annoying vibration for the past year and feel that I may have finally found it. Of course I have synced and valve adjusted the thing to death and today took the aftermarket trunk off the back. No vibration today but along with the aftermarket trunk I adjusted the valves one more time. So either I finally got the clearances right or this trunk bounces about at a very high frequency. I suppose I could put the trunk back on and see once and for all but I do not want to tempt the gods.

John

haha I'm glad it seems like I know what I'm doing This is my second fuel injected bike (first being the Honda, but I never did any tuning on it, it was too fast already) and my previous experience has all been carburetor based, so I'm just trying to apply what I know about fuel delivery to the injection system on the R1100. I removed the o2 sensor and have it running in open loop mode (euro spec was what I was going for) because I feel like I can tune it better that way and get rid of the surging better. The only thing I haven't been able to install is an idle regulating valve (the CO potentiometer) because for the life of me I can't find the plug. Seriously. I found the spot in the frame where it bolts to and the cutout in the plastic on the bottom of the bike where a screwdriver would be inserted to adjust the pot but no plug where it goes. I have two plugs down there on the right side of the bike but both are already connected to wires - one to the brake light assembly and the other to the ABS sensor. There's a three wire flat connector zip tied to the top of the fender but I think that's for some kind of fault readout.

So anyways... I really really hope it's something rattling like a top case but I have a gut feeling it isn't. I read somewhere else that the back of the RID vibrated and sounded like an engine rattle. I'll take the plastics, luggage, and top box off Thursday night and ride around and see if it's any better.

So far my plan of attack on Thursday is:
1) Put a bottle of octane booster in the tank on the way to work. Ride the 15 miles back and forth to work and see if it improves.
2) When I get home from work, take of all the plastics including the dash panels (includes switches and RID) and ride around for a bit.

Any other suggestions? One of my guesses was a clutch rattle but I have no idea what in there could be rattling. From what I've seen there aren't any damping springs (why?) so not much to rattle.

 

[flars]

rattle

If the HES plate has been repaired/replaced, the plate could have been put on with too much/too little advance.
You could try to adjust the timing by loosening the HES plate and moving it around a bit.

 

[waehrik]

If the HES plate has been repaired/replaced, the plate could have been put on with too much/too little advance.
You could try to adjust the timing by loosening the HES plate and moving it around a bit.

Excellent thought, I have no idea on the history of the bike so that well could be out of adjustment. I read through the BMW service manual which is of no help with timing (it requires a special tool) and I do not have a timing light. Is there another way that I can time the engine statically (kind of like looking at the voltage jump from 0-12v across points)?

 

[waehrik]

Update time as promised. I didn't have enough time after work to remove all of the body panels but I did do a bunch of other adjustments.

So far I've tried:
Tensioning the alternator belt, it was a little loose (from rattling noises in another thread recently posted)
Adding a '108 octane' booster, the entire bottle to 1/2 tank of gas
Retarding the timing a little. I don't have a timing light so I can't check it for sure but it's now aligned so that the hole in the timing plate lines up with the hole on the front engine cover. I had to rotate the plate clockwise to do that, so the spark is occurring later.

Unfortunately none of that helped. The bike runs quite well but the noise is very annoying. As a test I removed the 20k resistor that I used to replace the intake air temp sensor and the bike started to surge again a little at low loads, does that mean it's running too lean in that state? I put the resistor back in because it was much more driveable that way.
The funny thing is that the rattling noise is much louder when my head is out in the airstream than when I duck under the fairing's protection. Of course I'm out in the air all the time since I'm 6' and the RS's fairing is tiny.

I'll try taking off the body panels next chance I get (it's looking like rain up here in the Boston area this weekend) and report back on how that works.

Does anyone else have any suggestions? I do want to install a CO pot on the bike to complete the euro open loop conversion but can't find the plug. I'll start a new thread on that though.

 

[JimMoore]

Do you think it's pinging from detonation? I've never heard it before and the youtube videos seem widely varying on the subject.

Pinging sounds like a cofee can full of BBs being shaken vigorously. It's very distinct once you know what it sounds like.

I wonder if the PO installed GS intake tubes on your RS looking for more performance. When I did that to my RT it pinged like crazy. I went back to the RT tubes. In fact, I changed the tubes in my GS to RT / RS tubes because my GS pinged badly with the stock GS tubes installed.

There is a discussion at the ibmwr site about intake tube swapout. It should be pretty simple to see if you have GS tubes in there. You can also check part numbers at the MaxBMW website.

 

[waehrik]

Pinging sounds like a cofee can full of BBs being shaken vigorously. It's very distinct once you know what it sounds like.

I wonder if the PO installed GS intake tubes on your RS looking for more performance. When I did that to my RT it pinged like crazy. I went back to the RT tubes. In fact, I changed the tubes in my GS to RT / RS tubes because my GS pinged badly with the stock GS tubes installed.

There is a discussion at the ibmwr site about intake tube swapout. It should be pretty simple to see if you have GS tubes in there. You can also check part numbers at the MaxBMW website.

Yep, it sounds like a coffee can full of BBs shaking around! I've never had a pinging noise diagnosed before so this is the first time I've experienced it.
Good point on the GS intake tubes, the PO did fit them before I got the bike. I love the amount of torque it has and had heard only good things about the conversion so I saw no reason for changing it.
Remember my exhaust is essentially a straight through system with a stainless-packed slip on and silencer in the rear, so it makes sense that it was running rich originally. But with all of the steps I've taken lately I'm surprised that it's still detonating (retarded timing, added octane booster, tricked the air intake sensor into seeing colder air, increased TPS to 0.395v). I pulled the spark plug yesterday and it was mostly white with just a haze of brown on the insulator, which seemed like a good thing. Thankfully no metal flakes!
Does anyone in the Boston area have a set of RS/RT intake tubes I can borrow for a couple minutes to do a test? I'll ride over to you (and you can hear the joy of this awesome noise)

 

[JimMoore]

Does anyone in the Boston area have a set of RS/RT intake tubes I can borrow for a couple minutes to do a test? I'll ride over to you (and you can hear the joy of this awesome noise)

Post up in the Flea Market. You can try here, www.bmwsporttouring.com, and www.advrider.com. Someone will have a set. Or check with the PO. He may still have them.

 

[Ken F]

http://cgi.ebay.com/ebaymotors/94-B...4941152QQptZMotorcyclesQ5fPartsQ5fAccessories

 

[cycleman2]

Something isn't adding up. Pinging is normally only found on accleration, not deceleration.

In one of your posts I believe you said the rattle will fall off if you pull the clutch in. What do you mean by that statement? Does the rattle disappear or just change its pitch.

If you are just travelling along at a steady speed or rpm is the rattle still present?

Something odd about a dealer wanting to do a straight trade? That's not normal.

I would also check anythng that attaches to the motor ie: crash bars, as well as any of the other bits. Try taping with a small plastic hammer or even a screw driver handle on everything you can get close to.

 

[waehrik]

Something isn't adding up. Pinging is normally only found on accleration, not deceleration.

In one of your posts I believe you said the rattle will fall off if you pull the clutch in. What do you mean by that statement? Does the rattle disappear or just change its pitch.

If you are just travelling along at a steady speed or rpm is the rattle still present?

Something odd about a dealer wanting to do a straight trade? That's not normal.

I would also check anythng that attaches to the motor ie: crash bars, as well as any of the other bits. Try taping with a small plastic hammer or even a screw driver handle on everything you can get close to.

I'm glad I'm not the only one for which things aren't adding up, this makes no sense at all for me.

It is making the noise (BBs rattling around in a glass jar would be a good description) on both acceleration and deceleration. There is no noise at all when under a steady load. I can accelerate and decelerate lightly and not have the noise either. When I pull the clutch in the motor will wind back down to idle and the frequency of the rattling (period, not pitch) follows the slowing down of the motor. It doesn't immediately go away when I pull the clutch in and does occur if I have the bike in neutral and rev the throttle so I didn't think it was the clutch throwout bearing. It also occurs if I hold the clutch in and rev the motor, which seems like it might eliminate anything in the transmission.

I've had the bodywork off quite a few times when adding running lights, converting to HID, etc and every time it's gone back on the noise is still there and hasn't changed at all. Whenever it stops raining I'll take it all back off and see if there's a change in the rattling.

If that doesn't work I'll also tear down the valve train (really don't want to do that though) and look for any scoring or wear. I remember reading about someone (I think on ADVRider) who had a very chewed out cam and follower after a fairly short number of miles and that was causing a ticking sound. I hope it's the bodywork.

I'm not too surprised that the dealer wanted to do a straight trade. They do far more business in sport bikes and the used trade in value of my CBR1100XX was $1000 more than the retail sale value of the R1100RS. Economically it was a great decision for them. Plus there was absolutely nothing wrong with the CBR and it came with a full leather tank bra, bar risers, and a touring windshield (all courtesy of the PO). The bike wasn't that valuable to me and I got it in at a fire sale price so the trade made sense to me. Unbeknownst to the dealer (who never looks at aftermarket accessories in the pricing of used bikes) the BMW had hard cases, Works Performance shocks front and rear, a Kisan signal minder, and headlight shield.

 

[cycleman2]

Have you got something, like a hose or auto stethascope that you can put to different parts of the engine, transmission & exhaust? Put one end up to your ear and the other at various locations on the engine. It will enable you to narrow down where the noise is coming from at idle.

If its doing it at idle as well then I'm thinking it might be alternator related. Maybe a bearing in the alternator. Throttle body rattles are also fairly common but easy to diagnose. When the bike is running just put your finger on the wheel the cable attaches to at the throttle body. If it goes away then you found your problem.

It doesn't sound like a timing rattle but sounds more mechancial in nature. Valves make more of a ticking noise than a rattle but there is a slight loading and unloading of the timing chain depending on wheither it is under acc or decleration but the tensioner would have to be badly worn to make noises like you describe.

 

[waehrik]

Have you got something, like a hose or auto stethascope that you can put to different parts of the engine, transmission & exhaust? Put one end up to your ear and the other at various locations on the engine. It will enable you to narrow down where the noise is coming from at idle.

If its doing it at idle as well then I'm thinking it might be alternator related. Maybe a bearing in the alternator. Throttle body rattles are also fairly common but easy to diagnose. When the bike is running just put your finger on the wheel the cable attaches to at the throttle body. If it goes away then you found your problem.

It doesn't sound like a timing rattle but sounds more mechancial in nature. Valves make more of a ticking noise than a rattle but there is a slight loading and unloading of the timing chain depending on wheither it is under acc or decleration but the tensioner would have to be badly worn to make noises like you describe.

I'm still not sure what pinging sounds like, but this noise sounds mechanical to me. It doesn't do it at idle unfortunately, but it will if I rev up the engine and let it spin back down to idle. While it's winding down it'll make the noise, just not as much as if it's under load while riding. It's a hard rattle like two parts coming together.

I'll pick up a mechanic's stethoscope at Autozone on my way home today. It's still raining till Thursday so it'll be a little bit until I can report back with the results of the test.

Unfortunately it's not the throttle bodies, I've tried holding the cam that the cable rides on and the noise didn't go away. I wish it were that, it would be an easy fix with the rebuild kit from Bing.

The alternator makes sense, it seems like it would be under a varying load while the engine is rapidly accelerating and decelerating. Any bearing wear seems like it would cause a rattle. It doesn't make the noise at idle or constant load though.

 

[lsouth3]

The tensioner COULD be broken. I replaced the left one but never heard the motor before the fix because I got it after it had been torn down. If it happens to be broken give me a shout. lsouth3@gmail.com

 

[waehrik]

The tensioner COULD be broken. I replaced the left one but never heard the motor before the fix because I got it after it had been torn down. If it happens to be broken give me a shout. lsouth3@gmail.com

I replaced the left one with the updated version hoping it would solve it but no luck. I'll pull the right one and check for damage. I'll be looking for plugged oil passages and a broken spring, is there anything else that might be an indication of damage in the tensioner?