Engine Vibration and runability fixed?

[R1100RSpurist]

I have posted before about my '95 R1100RS that had annoying vibration issues at higher RPM's and poor idling/ off idle behavior, i had tried everything, throttle sync, valve adjust, new intake manifolds and O rings. So i bit the bullet and took it into the local BMW, after $500 for 3 hours of labor and a new oxygen sensor that they are installing right now, I have hopefully concluded this dark period in RSdom. I will post as soon as i ride it again. Only thing is i feel a little bit like a dunce not being able to figure out something so relatively simples as an O sensor causing all my grief.

[Ken H.]

Please post the results after you get it back, because I too would be amazed if a new Oxygen sensor was the culprit.

[R1100RSpurist]

Well first ride today with new oxygen sensor, about 150 miles. First Impressions subtle ride ability improvements, especially of idle, but INFURIATINGLY the crazy vibe that increases in frequency from 3700RPM all the way to redline is still there, although it seems more refined now in its shake. I Paid BMW $500 for 3 hours of check over and the oxygen sensor, and they still didnt fix half to 3/4 of the problem i came in with, im not sure they even rode it. i dont know what else to do? comments or help anyone?

[smiller]

As Ken noted it's not surprising that the new O2 sensor didn't resolve the high-rpm vibration issue, not sure why the dealer would expect it to. I would assume that they did a careful TB sync (and checked the TPS and other issues suggested in your prior thread) as part of the diagnostic process so not sure what to think. Have you compared to another bike? Perhaps the dealer has a similar used model that you could test ride and compare. If yours is really excessive and the engine is in a known good state if tune than then maybe check for any subframe cracks or similar issues that may be at fault.

[AndyS]

Has your bike always had this vibration issue? I ask because after you and a dealer looked at the bike and have tackled ignition timing, injector set up, coil operation and so forth, I am led to believe it is to do with engine balance tolerances - maybe you have a friday afternoon engine. If that is the case then to cure it, means surgery to have the internals balanced.

Andy

[big-t]

As Ken noted it's not surprising that the new O2 sensor didn't resolve the high-rpm vibration issue, not sure why the dealer would expect it to

 

 

One would assume the dealer saw a problem with the o2 and replaced it for whatever reason,slow response time or maybe a heater problem, rather than replacing it as a cure to a vibration problem. Nothing like ignoring a defective part and have it come back and bite you in the butt,two days later.

 

Being a 95 model,it should have a single throttle cable,which is almost impossible to keep in perfect sync thruout the whole RPM range.Thats assuming everything else is performing correctly.

 

You can play around with the rpms you sync it at and that will sometimes help to smooth out the range where its used the most,but the best bet would be to change it over to a dual cable arrangment.I'm sure someone on the board has those part numbers.

[Ken H.]

Has your bike always had this vibration issue?

Yes, tell us more about the history of the bike and the problem.

[R1100RSpurist]

When I first had the bike, it had older tires and i was a begging rider, so i did not take it up very high in the RPM range as i would up shift to the highest gear quickly (i.e. short shift), 5 or so months later, new tires levered on, and more confidence in the hopper, along with the experience that motorcycle engines like reving, I noticed and uncomfortable vibration once the tach went above ~3600 RPM that only increases in frequency as the RPM goes up. Its not the tires or the chassis, as when i pull the clutch in at say 5000 RPM the vibration goes away, so definantly the engine. I have twinmaxed this thing to death, and to verify this, the dealer said it was so close they didnt touch it. The only o ring on the throttle body i have not replaced are the fuel injection/hose ones. Im sure they would have checked the internals they had the bike for 2 weeks and over three hours.

[Ken H.]

Have you ever ridden another similar vintage one as a comparison? Not saying that there isn't something wrong with your bike, but these are after all a big twin.

[R1100RSpurist]

No, I have never ridden another oil head of similar vintage, but I would be very interested finding out if mine is fundamentally flawed.

[T__]

No, I have never ridden another oil head of similar vintage, but I would be very interested finding out if mine is fundamentally flawed.

 

Owen, some vibrate & some vibrate more.. Remember those early engines do not use a balance shaft & are solid mounted to the frame.. I had an R1100 that was pretty darn smooth but my friend had basically the same vintage bike & it vibrated pretty bad..

 

My current R1150RT has a few pretty obnoxious vibration points (especially in the lower gears with high RPM but no engine load to speak of)..

 

Run your bike up to well above the offending RPM then hit the kill switch & allow it coast back down through the vibration point (leave the throttle where it was, don’t close it) .. If the vibration is still there you have an inherent 1st or 2nd order vibration problem if it is gone or less intensity then look to engine firing frequency or uneven running as the contributor..

 

You need to find someone with a similar bike (year, model, amount of miles) & either have them ride your bike or you ride their’s..

 

Remember that the exhaust system is solid connected to the engine so it is getting excited by both engine vibration & firing power pulses.. If that is vibrating against the frame, or other area it could be causing a secondary vibration (check it’s mounting & isolation)..

 

Where are you feeling the vibration? Foot pegs, seat, or handlebars?

 

Twisty

[R1100RSpurist]

twisty and others thanks for your input, i contacted the previous owner, and he very informative and nice about wanting to help me out, and show me the tricks of the trade, ill tell you what we do and to what affect it has after.

[Ozonkiller]

Where is your oil level? I went ape trying to find the source of a vibration that would come and go. I did all of the stuff, TPS zero, TB synch, valves tight, valves loose, different spark plugs, yada, yada, yada...

 

Through a long chain of events and a lot of experimentation I found the source of vibration in My '96 RS to be related to the oil level. Windage, I guess. As little as 100 cc's of oil would make the difference between smooth and not so smooth. I now run my oil level in the bottom 1/4 of the glass or lower. Smooth as glass.

 

At oil and filter change, I put in 3 qt's and slowly add more until I can just see a level in the bottom of the glass.

 

When I first discovered this I thought "Naw, It can't be this simple." so just prior to my next oil change, I added a couple of ounces of oil and BINGO, the vibration was back.

 

Worth a try. If, at the last oil change, the customary 4 qts. was dumped in, on my bike that would be too much.

 

Good luck,

 

Tom

[smiller]

Where is your oil level? I went ape trying to find the source of a vibration that would come and go. I did all of the stuff, TPS zero, TB synch, valves tight, valves loose, different spark plugs, yada, yada, yada...

 

Through a long chain of events and a lot of experimentation I found the source of vibration in My '96 RS to be related to the oil level. Windage, I guess. As little as 100 cc's of oil would make the difference between smooth and not so smooth. I now run my oil level in the bottom 1/4 of the glass or lower. Smooth as glass.

 

At oil and filter change, I put in 3 qt's and slowly add more until I can just see a level in the bottom of the glass.

 

When I first discovered this I thought "Naw, It can't be this simple." so just prior to my next oil change, I added a couple of ounces of oil and BINGO, the vibration was back.

 

Worth a try. If, at the last oil change, the customary 4 qts. was dumped in, on my bike that would be too much.

I have noticed this effect too and it can be very prominent. There is a significant increase in vibration on my bike (also a '96) when the oil level rises above some point between the red dot and the top of the sight glass.

[Tipover_Bob]

Where is your oil level? I went ape trying to find the source of a vibration that would come and go. I did all of the stuff, TPS zero, TB synch, valves tight, valves loose, different spark plugs, yada, yada, yada...

 

Through a long chain of events and a lot of experimentation I found the source of vibration in My '96 RS to be related to the oil level. Windage, I guess. As little as 100 cc's of oil would make the difference between smooth and not so smooth. I now run my oil level in the bottom 1/4 of the glass or lower. Smooth as glass.

 

At oil and filter change, I put in 3 qt's and slowly add more until I can just see a level in the bottom of the glass.

 

When I first discovered this I thought "Naw, It can't be this simple." so just prior to my next oil change, I added a couple of ounces of oil and BINGO, the vibration was back.

 

Worth a try. If, at the last oil change, the customary 4 qts. was dumped in, on my bike that would be too much.

I have noticed this effect too and it can be very prominent. There is a significant increase in vibration on my bike (also a '96) when the oil level rises above some point between the red dot and the top of the sight glass.

 

I recently did the whole bit and checked the oil level using the "dance". I noticed the oil was above the sight glass and consequently lowered the oil to exactly to the dot. The bike is running much smoother. I had assumed it was my wonderful work on tuning the engine. Instead may have been the oil level.

 

Tipover Bob

[motoleo]

I recently did the whole bit and checked the oil level using the "dance". I noticed the oil was above the sight glass and consequently lowered the oil to exactly to the dot. The bike is running much smoother. I had assumed it was my wonderful work on tuning the engine. Instead may have been the oil level.

 

Tipover Bob

 

Bob,

Just got my RT and I'm curious how did you remove the excess oil to get the level down lower?

[Tipover_Bob]

Lenny:

Make sure bike is cold, just put a catch can under it while on the center stand and loosen the drain plug. Let a little out at a time until the oil is where you want it.

 

Tipover Bob

[smiller]

Make sure bike is cold, just put a catch can under it while on the center stand and loosen the drain plug. Let a little out at a time until the oil is where you want it.

That is the quickest and easiest method. Another way is to remove the filter and dump the oil. This removes the chance of having the drain plug slip out of your fingers and dumping oil everywhere. Not that this ever happened to me of course...

 

If you use the oil filter method remember to do the 'dance' afterwards (engine to operating temperature, sidestand for ten minutes, then on centerstand to check oil level.)

[T__]

I recently did the whole bit and checked the oil level using the "dance". I noticed the oil was above the sight glass and consequently lowered the oil to exactly to the dot. The bike is running much smoother. I had assumed it was my wonderful work on tuning the engine. Instead may have been the oil level.

 

Tipover Bob

 

Bob, so you did a wonderful job tuning the engine then lowered the oil level (just slightly) & you think the oil level was the reason of it running smoother? Maybe lowering the oil level a quart or two I could understand but a few ounces or even less I find that difficult to understand.. Note: I didn’t say I don’t believe that YOU believe the oil level was the cause.. I just said it is difficult for ME to understand (both engineering wise & theory wise).. The crankshaft doesn’t come anywhere’s near that oil..

 

Twisty

 

 

 

[motoleo]

Make sure bike is cold, just put a catch can under it while on the center stand and loosen the drain plug. Let a little out at a time until the oil is where you want it.

That is the quickest and easiest method. Another way is to remove the filter and dump the oil. This removes the chance of having the drain plug slip out of your fingers and dumping oil everywhere. Not that this ever happened to me of course...

 

If you use the oil filter method remember to do the 'dance' afterwards (engine to operating temperature, sidestand for ten minutes, then on centerstand to check oil level.)

 

One problem I am having is I really can't tell where the level is. I think its very high in the sight glass but the sight glass itself is so dirty and scratched its hard to see. I just had the 6000 mile service done about 725 miles ago so I am assuming its full although I've been warned about high oil consumption until about 20,000 miles are on the bike.

 

What should I be using on the sight galss to clean it? I don't want to make it any worse. Is the sight glass plastic or glass?

[Bob Palin]

Bob,

Just got my RT and I'm curious how did you remove the excess oil to get the level down lower?

Unscrew the oil filter, empty, replace.

[smiller]

One problem I am having is I really can't tell where the level is. I think its very high in the sight glass but the sight glass itself is so dirty and scratched its hard to see.

The sight glass isn't that difficult to replace if necessary.

 

The crankshaft doesn’t come anywhere’s near that oil.

That would appear to be the case so the effect must be caused by something other than windage, but nevertheless it does exist. The difference in vibration is not a slight psychologically-generated nuance, it's very noticeable and directly related to oil level.

[Don_Eilenberger]

Bob, so you did a wonderful job tuning the engine then lowered the oil level (just slightly) & you think the oil level was the reason of it running smoother? Maybe lowering the oil level a quart or two I could understand but a few ounces or even less I find that difficult to understand.. Note: I didn’t say I don’t believe that YOU believe the oil level was the cause.. I just said it is difficult for ME to understand (both engineering wise & theory wise).. The crankshaft doesn’t come anywhere’s near that oil..

 

Twisty

When I had my buzzer - the '04 R1150RS (hey - it's for sale if you want to feel what I meant - ping me for the dealer who has it..) - I also read this, and being desperate for ANY improvement, played around with oil level from none showing in the window to top of the window.

 

NO change - and not a surprise since the rotating bits are about 8" above the top of the oil when it's full up.

 

I suspect some of the engines just aren't balanced all that well - and with two big pistons wacking back and forth have the propensity to make a noticeable vibration. Plus - some people seem much more bothered by it.

 

I spent a buncha time, a buncha money and pulled a lot of hair out and never really got the level down to reasonable. With a full tank of fuel it was rideable - when it got below 1/2 tank, I just wanted to be OFF it. I replaced it when I realized I was cancelling trips since I didn't want to ride the damn thing.

 

FWIW - I'm delighted with my hexhead - R1200R - no vibes at all to speak of until about 5.5K - and up to where I max out on RPM - its still less annoying than the R1150 was. It's about as smooth from 3k-5k as a K75S - which is the gold standard for smooth/no-vibration. Have 4,500+ miles on it since mid-May.. and it's been ridden almost every day since it came home.

 

Some bikes and some riders just aren't gonna ever be happy with each other. That was me and the R1150RS - best bet - move on..

[Tipover_Bob]

Don:

It's not too bad. I was just surmising that some of the improvement was due to my lowering the oil level to the dot.

 

I must agree that my K75C was a bunch smoother. It didn't handle as good, nor go as fast, but it was very smooth. May account for why you see so many K75s at rallys, in addition to their longevity.

 

Tipover Bob

[smiller]

I must have an unusually good 1100. While some vibration is present (of course) it's never objectionable or troublesome and the two 1200RTs that I've ridden seemed only marginally better (and a 1200GS seemed worse.) All-in-all for a solid-mounted twin I would consider the engine to be pretty smooth. Guess I'm lucky?

[big-t]

Quote:

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The crankshaft doesn’t come anywhere’s near that oil.

 

 

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That would appear to be the case so the effect must be caused by something other than windage, but nevertheless it does exist. The difference in vibration is not a slight psychologically-generated nuance, it's very noticeable and directly related to oil level.

 

 

 

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