Help request: Vibrations

Post by **OlyVR** » Fri Aug 17, 2007 7:31 am

Hey guys I hope you can help. What used to be the smoothest, best running bike has turned into a '74 Shovelhead with broken motor mounts...

My bike has developed a vibration in the last 500 miles.
Where previously I only had a buzzy spot at around 4k RPM's it is now anywhere above 3,000 rpm and getting worse as the revs go up. Under acceleration it is also worse than just cruising.
Forget seeing anything in the mirrors and trying to keep your hands from going numb.
Dealer tells me this is normal and to ride it hard.

Since I disagree with him I bought a Twinmax and looked up the instructions for setting valves and found the following:
-Adjusted the valves and it made a little bit of a difference, but not much.
- Sync'd the TB using a Twinmax @ 2,000 and 4,000 RPMs. However, when i let off the gas the Twinmax shows it idling between -2 and -3 on the right hand side of the twinmax scale - is that normal?

Any help to a possible cause would be greatly appreciated.

Also, does anyone have experience with the BMW Motorcycle dealer in Charlotte, NC? In case I want/need a second opinion.

Thanks!

Post by **AllanCook** » Fri Aug 17, 2007 7:56 am

You might have a look at this link:

http://www.advrider.com/forums/showthread.php?t=131613

Mine is a bit vibier than my 1150, but usually I just power through the rough patches.

Post by **OlyVR** » Fri Aug 17, 2007 8:13 am

AllanCook wrote:You might have a look at this link:

http://www.advrider.com/forums/showthread.php?t=131613

Mine is a bit vibier than my 1150, but usually I just power through the rough patches.

Allan,
I did find Advriders and got my instructions from there, but I'm not quite sure why you sent me there. What are you referring to in that post that i'm missing?
- Adjust TB's to "0" at 2k and 4k - check!
- Check/Adjust valve clearance - check!

Which brings me back to my earlier question. Since idle is controlled by the stepper motors, is the vacuum difference at idle normal?

Post by **deilenberger** » Fri Aug 17, 2007 8:28 am

OlyVR wrote:Which brings me back to my earlier question. Since idle is controlled by the stepper motors, is the vacuum difference at idle normal?

Nope. Sounds as if your steppers aren't working right.

Right after I adjusted my valves - I hooked up the TwinMax to check sync. The TB's were off a bit at idle. They were dead-ntz(tm) on. After warming it up a bit and rev'ing it to around 4k - they were also dead-nutz(tm) on at idle. -2 -3 is too far off to be acceptable. If it were going 0 to -1, that would be within reason.

Have you retrained the Throttle-Position-Sensor (ignition on, engine off - open throttle fully 2 times..)? If you had the battery disconnected for some reason this apparently needs to be done.

FWIW: I do notice I can feel a slight increase in vibes when the outside temperatures are hot.. and since you're in NC which I've heard is cooking in 100F temps at the moment - just a thought.

Post by **deilenberger** » Fri Aug 17, 2007 8:38 am

Looking at the thread Alan referred to I found:

Poolside
85Ã‚Â° and sunny
Joined: Apr 2003
Location: Long Beach, CA
Posts: 3,193 Quote:

Originally Posted by Tslepebull

. . . I also commented that on my TwinMax it showed more air being drawn through the left than the right cylinder at idle. He said that they come from the factory that way and if adjusted to be exactly the same it leads to some pulsing or surging at idle. Has anyone else heard this?
It can become clearer if you consider the use of the term 'balance' to really mean 'balanced crankshaft speed'.

And, that often the state of 'balanced crankshaft speed' is reached by a slight offset in the intake air between cylinders.

The widely used term 'balanced', to describe the state of equal TB intake vacuum levels, is a bit incomplete/misleading.

The 'balance' that is strived for is the state of equal crankshaft rotation speed.

You know, the state of equality between the speed that the #1 cyl power cycle pushes the crank around, and the speed that the #2 cyl power cycle pushes the crank around.

Variance in the two TBs intake vacuum is only indirectly related to variance in crankshaft speed.

There are many other variables that have an equal impact on 'balanced crankshaft speed'.

To list only two:

One variable is: Valve timing differences between cylinders due to the ridiculously inexact operation of the three cam chains and their floopy damping system which alters cam timing between cylinders over changes in RPM, changes in oil viscosity, and cam chain damper wear.

Another variable is: Variance in fuel injector minimum response/cycle time.

The two variables above have an equal ability to affect the 'balance' of crankshaft rotations as TB vacuum. And both of the variables above affect intake vacuum.

And . . both variables above are 'un-adjustable'.

Adjusting the single variable of TB vacuum is designed to adjust for all of the many other 'un-adjustable' variables.

And as a result, the state of 'balanced crankshaft speed' may be reached by a slight offset in the intake air between cylinders.

- Jim

That's an interesting thought. I'm of a mixed opinion if it's total BS or not. I'll puzzle over it and decide later..

Also - as a sidenote.. mine does have some rock/vibration to it at idle, even with perfectly adjusted valves and TB's apparently sync'ing.

The stepper motors - as far as I can find out - only work as a replacement for the "big-brass-screw" on the oilheads. Meaning they adjust a fairly small bypass air passage. Since the relative sizes of the bypass air passage compared to the actual throttle-throat is small, I suspect (no evidence - but experience) the steppers have very little effect above 2,000 RPM and practically none at 4,000.

Now - I could be all wet here since I haven't disassembled an oilhead TB.. if the steppers worked directly on the throttle cable position - then they could have an effect at higher RPMs..

Brain-noodling on a Friday in NJ..

Oh - one additional comment... my R1200R has no vibration at all compared to the '04 R1150RS that I traded in on it. If you have objectionable vibration in a Hexhead - something IMHO is - wrong.

Post by **OlyVR** » Fri Aug 17, 2007 9:19 am

Don,

I also think something is wrong, but my dealer doesn't. Apparently to him I am the automotive equivalent of a hypchondriac (sp?).

Thanks for reminding me about the TPS relearn. I forgot to mention that I tried that as well in order to see what could be causing it. It was one of the first things I tried. I disconnected the battery for about 15-20 min. to clear everything and then reset the TPS. Did it again after a day of riding. No change - so that apparently wasn't it.

Please keep me posted on what your "brain-noodling" in NJ will come up with.
To give you some more brain food: Temps do not have an impact as they are the same in morning or afternoon (am: 70s/80s; pm: 90s/100s).

Thanks!

Post by **deilenberger** » Fri Aug 17, 2007 11:07 am

OlyVR wrote:Don,

I also think something is wrong, but my dealer doesn't. Apparently to him I am the automotive equivalent of a hypchondriac (sp?).

Ask him for a ride on their R1200R demo bike.. that should settle if you're imagining it or not. I doubt if you are - and would love to know what changed causing your bike to vibrate more. Once you determine your bike does vibrate more than the demo bike - send THEM out for back to back test rides..

Anything you can think of you changed around when it started bothering you? I have noticed some difference with different brands of fuel. For some reason mine really likes Shell - and of course there are very few Shell stations left in NJ..

Thanks for reminding me about the TPS relearn. I forgot to mention that I tried that as well in order to see what could be causing it. It was one of the first things I tried. I disconnected the battery for about 15-20 min. to clear everything and then reset the TPS. Did it again after a day of riding. No change - so that apparently wasn't it.

Please keep me posted on what your "brain-noodling" in NJ will come up with.
To give you some more brain food: Temps do not have an impact as they are the same in morning or afternoon (am: 70s/80s; pm: 90s/100s).

Thanks!

Too bad on the temps - that would have been easy. Any change of clothing? Gloves? Boots?

Post by **OlyVR** » Fri Aug 17, 2007 11:27 am

Clothing is not a variable, as I work for a place where we have uniforms, so the pants, shoes etc are the same.
Don't know if i mentioned it, but level of vibration increases under acceleration.

Post by **celticus** » Fri Aug 17, 2007 11:57 am

Oliver, I think that level of vibration is NOT normal at all.
I am heading to NC tomorrow (or tonight if I change my mind) to Boone for the Boone rally. Meet me there and I'll let you see what I consider normal (for an R1200R to vibrate I mean).
Mark

Post by **OlyVR** » Fri Aug 17, 2007 12:08 pm

Mark,

I may just take you up on that, unless i can be successful in leaning on the dealer to hook it up to the computer tomorrow.

In case I'll make it up there, can you pm me your cell phone#?
I'll send you mine as well, so that you have an idea who's on your caller id.

Thanks

Post by **OlyVR** » Fri Aug 17, 2007 1:45 pm

Turns out last time they only drove it and deemed it "normal" even though I specifically requested it to be hooked up to the diagnostic computer.
I'll drop it off again tomorrow for them to hook it up (hopefully for real this time). Let's see where this will go...

Post by **celticus** » Fri Aug 17, 2007 3:31 pm

That "leaning on them" thing sounds like a good idea.
Mark

Post by **OlyVR** » Mon Aug 20, 2007 8:11 am

The service manager and the operations manager both took a spin and couldn't find anything wrong. The computer also didn't throw out any error codes.

Therefore it must be me to think it is wrong to think that vibrations should not:
1) Continually Increase under acceleration (not just a vibey spot at x,xxx rpm). They are most noticable from 4,500 rpm ONWARD
2) Cause my hands to go numb after 10 minutes.

The thing only has 2,900 miles on it and for the first ~2,500 I couldn't wait to get on it, now I can't wait to get off it.

Does anyone have any ideas?

Mark [Celticus]
I really appreciate the offer for a comparison, but by the time i got it back on Saturday (5pm) it was too late to head to Boone and back, especially since I also had a family member in the hospital.

Post by **deilenberger** » Mon Aug 20, 2007 8:29 am

OlyVR wrote:The service manager and the operations manager both took a spin and couldn't find anything wrong. The computer also didn't throw out any error codes.

Therefore it must be me to think it is wrong to think that vibrations should not:
1) Continually Increase under acceleration (not just a vibey spot at x,xxx rpm). They are most noticable from 4,500 rpm ONWARD

There is some level of vibration above 4,500-5,000 RPM - it's the nature of the counter balance shaft that it was tuned to eliminate most vibration at lower engine speeds - at the expense of slightly increased vibrations above normal "cruising" speed..

That said - it sounds as if the behavior has changed? It isn't a case of your riding behavior changing?

FWIW - I almost never run above 4,500-5,000 RPM as a steady state speed, and the increase in vibrations above that speed is a transient thing since once I'm at about 5,500-6,000 RPM I'm looking to shift up. There is some vibration there - but I'm not at the vibration range long enough for it to bother me.

2) Cause my hands to go numb after 10 minutes.

Having had this problem on my R1150RS I can sympathise with you. I have had my right hand go numb on the R1200R - but that's a combination of some carpal tunnel damage, and too tight a watchband. I found if I take my watch off, and only fasten my gloves very loosely - it's a non-issue. I might also suggest the slip on foam grip covers from BeemerBoneyard. The larger diameter helps arthritic hands a lot, and the foam does damp out a bit of vibration. I find BMW grips in general too damn small in diameter for my hands.

I also added an O ring between the throttle and the throttle housing to create a neutral throttle (drag) - where it stays where I set it, but it easily opened or closed. Again - helps a lot with hands going numb since it isn't necessary to grip the throttle tightly to keep it open.

The thing only has 2,900 miles on it and for the first ~2,500 I couldn't wait to get on it, now I can't wait to get off it.

Something obviously has changed..

Does anyone have any ideas?

Mark [Celticus]
I really appreciate the offer for a comparison, but by the time i got it back on Saturday (5pm) it was too late to head to Boone and back, especially since I also had a family member in the hospital.

I think you really do have to make the effort for a comparison ride on another R1200R.

I've also found fuel quality seems to make a dramatic difference in how smooth and powerful my engine feels. Not necessarily by brand (one Sunoco station vs another..) It may be fuel additives, or it might be one station cross-pumping the premium with low-test - but I can tell when I have a "good tank" and a "buzzy tank". On my old R1150RS - this made the difference between being able to ride it 100 miles vs 25.. the R1200R - the vibration remains so low that it's a non-issue.

Post by **OlyVR** » Mon Aug 20, 2007 9:38 am

Don,

Thanks for taking the time.
Some of the things you have addressed I have already tried, which is why I am so frustrated at the change in the bike and not being able to pin point it:

I've had the slip over foam grips from day one pretty much, as the skinny hard rubber grips weren't doing it for me. I have the caterpillar o-ring cruise control and it doesn't really help.
You are right, something has changed. At cruising speed I used to be able to see out of the mirrors...

Next I'll try a different gas and just for S&G's I may just try an injector cleaner (not that they should be dirty with so few miles).

Post by **celticus** » Mon Aug 20, 2007 11:41 am

If your dealer can't find the peoblem then come try my dealer just west of Knoxville Tn. Destination motorcycles. Hard excelleration on mine and I imagine any other R1200R is a rush akin to a well...a rush where I make childish sci-fi noises with my mouth.
You missed a good time in Boone. I saved you a parking spot.
Mark

Post by **OlyVR** » Mon Aug 20, 2007 2:56 pm

I may just have to find a different dealer, as even a set of monster bar end weights (Manic Salamanders - biggest one's they have) didn't make a bit of difference.