2004 R1150RT Vibration

Hi All,

Let me first add my accolades to this fine forum and all the friendly and knowledgable people who help out newbies like me.

I have a 2004 r1150rt that I've put nearly 60k miles on. I have engine roughness (high frequency vibration) at about 4000+ rpm . It's most noticable when there's a load - uphills, passing, headwinds, etc. I had replaced the fuel filter 10K miles ago.

Here's what I've tried so far:

4 new spark plugs

adjusted valves

sync'd TBs

installed new stick coils (both)

check ignition wires for corrosion (none found)

check resistence on secondary coil (right on)

polished primary coil grounds

checked for vacuum leaks

re-adjusted valves

When none of these things worked, I took it to the BMW dealership, reported the problem, and had them install new throttle cables and sync TBs, and find the problem. Afterward, no change to vibaration at all. The BMW mechanics can't figure what it might be (nor did they sense the vibration).

It does feel to me like a bike with mis-sync'd TB, or maybe an electrical miss, maybe.

I've spend over a grand in parts, labor and lost wages looking for the fix.

Does anybody have any suggestions?

Thanks in advance to all for your help.

Hi Bud

Well first you need to find another like BMW 1150 then ride that a while. All BMW boxers buzz in the 4000 RPM+ ranges, some are worse than others and most get worse at higher throttle openings or under high speed loads like climbing hills.

Things like TB balance and ignition misfires make more difference in the lower RPM ranges like mid throttle at 3000 RPMs.

That could be one reason your BMW dealer couldn’t find the problem as they thought it was just normal BMW boxer engine buzz at 4K.

Keep in mind the BMW boxer engine is an inherently primary balanced engine as the pistons offset each other on moving weight. The problem or basic buzz comes from the fact that both pistons start and stop completely at the top and bottom of each stroke, that is further complicated by the fact that the pistons are not directly across from each other due to being on separate crankshaft throws. What that basically means is each time the pistons start or stop they want to rock the engine on it’s axis. That is called rocking couple. This is amplified by harsher firing pulses of a hard working engine like wide open throttle or climbing a hill.

Now the above doesn’t mean you don’t have other issues like a mis balanced flywheel or a clutch out of balance or other imbalance in some rotating or reciprocating part or parts. Or something loose on the bike like engine bolts or frame bolts or a grounded out exhaust.

If you ride another 1150 and determine you bike is actually worse than others then you will have to go after the problem.

Start with checking ALL the engine and frame bolts for being tight, make sure the exhaust isn’t contacting the center stand, make sure the compression is even side to side.

You might try lowering your engine oil level slightly to just below the center of the sight glass. While I haven’t ever been able to see the difference some riders report that the engine vibrates more with a high oil level in the crankcase.

If your primary objection to the buzz is hand grip excitation or buzz then maybe try some larger bar end weights as that helped my old 1150 a fair amount in the freeway grip buzz area.

Again ALL the BMW boxers buzz to some extent in the 4000 plus RPM range, some worse than others. You can chase all the problematic areas and maybe improve it some but will never get rid of it. The other problem is rider sensitivity, it seems once a rider tunes into that buzz area it becomes bothersome. Some riders never seem to feel it while others are bothered to the extremes by the very same bike.

You have "engine roughness" since?

replacing ff, since new, ?

If since new, it may be TADT or an issue that involves an internal part like dirtrider said.

What type of oil and other fluids are you using?

Have you owned other boxer/airheads/oilheads?

Maybe someone else should take it for a spin.

Good luck.

I don't know if this helps or not, but I have a 2004 1150RT and in the past had a 2002 R1150GS and they both had a buzz or vibration between 4 and 5K RPM. I think it may be the nature of the beast.

Marc

Thanks for the suggestions, and I'm sorry for being vague about the problem.

I've had this m/c since 2005 when it had 3,200 miles on it, it's just about to turn 62,000 miles, so I know there's definitely something wrong. Seriously wrong.

I was at the dealership on Friday - 2 days ago. After they completed work, I tested it and brought it back and told them there was no change in the problem. Two of the mechanics rode it in town, but couldn't really appreciate what I was talking about. I then rode it home (130 miles) in cold and wind, and it was the same roughness.

Now, I just returned from a warm 230 mile jog, and my hands are still buzzing. The bike is, for the most part, unridable. The buzzing is throughout the bike - bar ends, seat, and foot pegs.

This problem started in July of this year when I went to Oregon for the Rally. It was quite hot there, and that's when I noticed it. Upon returning home is when I started the resolution attempts I've listed above. I would say the problem is not noticable when the bike is cold. Once the bike is hot (operating temp. hot), then it's quite noticable.

I think my next move will be a leak-down test of the cylinders.

Is it possible the cat converter might be failing and causing exhaust resistance?

If you have or can get your hands on a twin-max hook it up and tape to top of gas tank then go for a ride and see how the throttle body balance looks under load. Has anyone ever fooled around with the throttle plate stop screws to set idle?

sometimes doing all the usual things will not cure the problem,

the r1100s i have owned from new, has progressively over the years shown a change in the idle screw settings. when the bike was new the throttle bodies were balance with equal turn out for the idle it was more than 1 turn difference this year, and the vibration at speed over 3500 rpm was not right, as you, i tried a whole list of possible fixes.

Ken was able to point me in the right direction. i was observing that a sync at idle using the BBS was not the same after a throttle cable adjustment at off idle or at 4000 rpm.

I was able to get the smoothness back by doing the following;

1. anal valve adjust

2. new plugs

3. clean the idle bypass passage

4. set the BBS to 1 turn out from the stop (not running)

4a. ensure full slack in the throttle pull cables

5. start bike and set idle balance using the right throttle stop screw. ( this is much more difficult to do then say)

in a nutshell something changed in one of the throttle plate positions, and they were not opening identically.

i have only had the bike out for a short highway spin to confirm that it is much better.

difficulties to be aware of, the right side throttle stop screw is horrible to access, and not free turning, i finally removed the TB to allow better access to the stop screw, take lots of measurements as the process of freeing up the threads will in all likely hood mess up the starting point,

you really need to have a pair of vacuum gauges to cover the wide variation of vacuum as you dial in the stop, a manometer is only good if these are really close

Here's my longshot guess: Remove the BBS (Big Brass Screws) and clean them. You may also want to replace the o-rings if you haven't already. If you can't find the right size o-rings, just but some new BBS's; they're relatively cheap. You'll have to do a sync afterwards.

Tony

JamesW, no adjustments have ever been made to the stop screws, nor to the TPS.

ProductUser, thanks for that tip. I'll give that a try too.

Santa, good suggestions. A friend with a lot of knowledge suggests I install a chip - Techlusion, or Power Commander -- along with a type of zero-zero TPS. Would this be similar to the stop screw adjustment you are talking about??

If it wasn't there before but it is now then I might assume it's fixable.

Just some thoughts:

Check for excessive carbon deposits.

Check the cam timing on both sides.

Are the final drive joints phased correctly?

Is the vibration there in every gear? or is it really road speed related?

Does the vibration get worse as the revs rise or does it smooth out again.

Hi again Bud

Ok, the new information you furnished definitely points to you noting more vibration now than it used to have.

We still have that magic switch point of 4000 RPMs though. While it sure wouldn’t hurt to do a leak down test and other engine balance and ignition tests it just doesn’t point in that direction. If you have leak down issues at 4000 RPMs you would surly have a big black hole at 1000-2000 RPMs. If your TB balance is off at 4000 RPMs it would also be felt at 2000 and 3000 RPMs. Unless way way off TB balance at wide open throttle becomes a non issue as there is very low engine vacuum and the intake restriction is not at the throttle plates.

Same with your coils, the secondary’s are all but out of the picture at 3500 RPMs+, if you had a primary acting up it would be very strange for it to not be felt at 3000 RPMs but suddenly become a problem at 4000 RPMs.

Your vibration problem comes in at the very same RPM as most BMW boxers start to vibrate and buzz. Coincidence that something else would fail or suddenly become out of adjustment at that very same RPM? Possible but highly unlikely.

First thing, go back over what you did to the bike just prior to your vibration complaint coming on. Did you install new tires, or change the engine oil, or have the final drive apart, or add anything like an air intake sensor tricking device, or remove the CCP, or change the exhaust, etc, etc?

If you did ANYTHING to the bike just before your problem came on go back and reverse that or at least verify nothing in that area is causing your vibration problems.

With your excess vibration coming on at the very RPM that most boxers vibrate my common sense tells me your problem is related to that inherent vibration period. This doesn’t mean you don’t have a valid problem it just means there is real good chance that your complaint is linked to the normal vibration period driving something else or coupling up with something else.

Something as small as slightly loose handlebar attaching bolts can allow the normal engine buzz to really excite the bar ends. Slightly loose steering head bearings can allow the whole bike to be driven by the normal engine vibration and cause the entire bike to vibrate.

If you have a loose starter or loose alternator those can be driven by normal engine vibrations and couple up to the main engine disturbance with it being felt throughout the entire bike.

How about the final drive? Any roughness in the rear large bearing can be felt in the foot pegs and seat. If that roughness falls on top of the normal engine vibration it can amplify the rider felt disturbance.

Is the exhaust grounding out to the frame or center stand? I have seen the center stand up-stop bend or deform allowing the center stand to contact the exhaust allowing exhaust order vibrations to be transferred to the bike’s frame.

Even something as simple as loose wheel bearings can change the shaking response of the frame and rider felt vibrations.

Anything loose on the engine attachment bolts or frame attachment bolts can allow the normal engine buzz to excite the bike differently than you are used to.

Obviously something like a worn drive shaft U-Joint or slipped drive shaft rubber dampener can allow a lower frequency shake to couple up to your normal high frequency engine buzz and drive the entire bike in a surround-like chassis buzz/vibration.

Something like a worn trans input shaft with matching worn clutch disk splines could allow the clutch disk to clamp down off center. That would be a lot of rotating mass way off center to effect the engine primary balance. Maybe try a downhill coast at speed in high gear while feathering the clutch to see it that can force the disk to center up then ride at the offending RPM without using the clutch after the center up try.

Even a tire or tires out of balance can add to the normal engine buzz and shake the entire bike while the high frequency engine buzz drives the chassis.

Have your tried riding the bike up to about 100 MPH then declutching and costing back through the offending speed?

How does the engine feel at the same offending RPM but in a lower gear? Can you get the same feel at 4000 RPMs in 4th gear?

Unless there is something blatantly wrong with your engine or bike I have a feeling your dealer will be of little help until you point them directly to the problem area. Go over the bike yourself and eliminate all the possible areas starting with what was done to the bike JUST before the problem started.

I had the buzzing and got rid of it, but in my case it was something really simple.

I have an '02 1150RT which I diligently maintain myself. On a recent short trip of under 100 miles the buzzing on the bars, particularly the right side, was so bad that my hand would go numb and I'd have to lock the Throttlemeister and shake my hand in the air to wake it up.

I know my bike was tuned to near perfection, so I examined the tires. I had recently changed to Metzler Roadtec Z6 Interacts (not that it really matters). I discovered my tire pressure was down by about 4 pounds. After pumping them up hard the buzzing was virtually eliminated. I also noticed the balance weight on the rim was missing. I have a feeling if I get the tire re-balanced the remaining excessive buzz will disappear.

Occam's Razor applied in my case.

Santa, good suggestions. A friend with a lot of knowledge suggests I install a chip - Techlusion, or Power Commander -- along with a type of zero-zero TPS. Would this be similar to the stop screw adjustment you are talking about??

Bud; the zero zero is always set on the left TB. and the newer r11150 like yours doesn't really need it. you can check your TSB voltage and it should be ~ 0.36 <0.385.

those addon electronic measures just hid the problem. it was smooth, now it's not, find the root cause, solve the problem, (you know that it's not as smooth as an inline 6cyl engine but all the same not as rough as Briggs and straton)

don't touch the left side, my problem was that one of the stops had changed, don't know how, but they were not the same. so i needed to adjust the right side to match the left even if the left was the one that changed. i was looking for match airflow and butterfly movement.

(so when i adjusted the cable slack they would not open with

matching air flow and if i set the balance at one point it would be out at another)

as noted there's a lot of good advice here, so start with the easy stuff first.

you will need to determine if the vibration is engine or road speed dependent, if you pull in the clutch at speed and let go of the throttle does the vibration cease? thats engine. if it doesn't its drive train/wheels/tires

valve adjust

plugs dirty one side worse then other

stick coils, and secondary coil

compression test

disconnect the computer power by pulling the fuse, and do the 2x throttle twist to reset the computer

check you tires are the old and worn/hard, replace, rebalance if needed, see above comments to check other possible drive train

after rereading you first post you do have a few miles on it, so drive train is possible cause.

just go through it methodically.

Zero-Zero Does not apply to the 1150. Do NOT fiddle with it.

Techlusion, or Power Commander will not rectify this.

These devices were kind of useful on 1100's and early 1150's to blend out surging. The 1150 of your vintage does not (should not) exhibit surging, and if it does can be tuned out.

You have some reasonable suggestions from users but do not mess with the Zero-Zero. You may have the Devil's own job of recovering good settings.

Andy

I've read that the zero-zero does not work for the 1150s with dual sparks, but what was proposed was a modification of that technique, not actually using zero, but some other value. In any case, I agree it's a risky venture, and I'll make that a last resort.

I believe this is an RPM issue. When I'm speeding along, then pull in the clutch, the vibration goes away. I've also feathered the clutch, but didn't detect any high spots, and am otherwise pretty certain there's no clutch slippage.

I have wondered if this could be in the drive train somewhere. I've only changed fluids. If the problem is in the drive train (final drive, u-joint, etc.), would you expect the vibration to disappear with the clutch engaged (pulled in)?

I'll try to get to these recommendations as soon as I can.

how's it feel in 6th at 4200 rpm+ ?

Hi again Bud

It could be in the drivetrain but keep in mind that the farther you get from the engine s far as gearing goes the buzz turns into a shake or lower frequency vibration.

Tires that are out of balance give you a one per rev jump or shake, that is a very cry from a high frequency mirror blurring buzz. You would have to be doing 150 mph to get any type of buzzing from a tire balance issue.

Same with U-joint slop or a slipped isolator joint phasing problem. That would be a higher frequency than a tire shake but much lower than the 4000 RPM engine buzz.

Now that isn’t saying you don’t have a basic normal engine buzz that is being overlaid with a slower speed lower frequency shake and the two together are what you are feeling.

You should be able to separate those by accelerating to well above your offensive road speed then coasting back through the offensive road speed with the engine idling or turned off.

If you can track your problem to ONLY the engine then you have either an engine problem, more than likely a primary balance issue or something out of balance in the basic engine transmission area. Maybe even something loose on the engine or loose bolts on the chassis or something allowing the engine to buzz a little more unrestrained than normal.

At the 4000 RPM range that is mostly engine mechanical as ignition and fueling is so fast at that RPM that it usually isn’t much of a contributor to high RPM buzz. The exception would be an engine disturbance that comes in at 1500RPM and builds as the RPMs get higher.

If you can track the buzz to just the engine then maybe put a couple of high flow fans on it then rev it in place to see if no clutch engagement and no spinning transmission effect the buzz. You might be able to track some of the offensive areas using a mechanics stethoscope on some of the engine accessories or frame parts.

One more thought. Have you looked at the rear swing arm bearings for being loose “try to twist or move the rear wheel in all planes with the bike on the center stand”. If those are loose it removes a lot of rear swing arm frame dampening from the chassis.

Another thought. Is your crankcase overfilled? If so start by lowering that to at of slightly below the center dot on the sight glass.

Brian, the vibes are bad at those RPMs in 6th gear, and I can't seem to accelerate out of it. I also noticed excess roughness at lower RPMs in 6th gear - around 3200 rpms -- as that seemed like a lugging-type of load to the engine.

Dirtrider, thank you so much for your help!

It's not the oil level. I've ridden with this problem at various sight-glass levels.

I did check for rear wheel play at one point and found no play at all (jiggling it at 9&3 and 6&12). But these are good suggestions, and I'll look again at all these issues when I get it apart.

AndyS,

I'd say it's there in every gear. Just seems more noticable in 6th gear. And as I mentioned above, I don't seem to be able to accelerate out of the vibration.

If I had the issue you are describing, I would start with a compression test/cylinder leakdown test. You are describing a mechanical imbalance, and the most likely thing to change is the balance of working cylinder pressure. Balancing the TBs will mask an issue here, but not eliminate it.

Next, I would check the alternator belt, and check the alternator for a rough bearing while I had the belt off.

If all those items are up to snuff, I would consider the clutch as a possible culprit. A bolt could have worked loose, or you could have a transmission input shaft starting to fail......Any trouble shifting?

Good luck.

Bud,

Going back to basics.

Did you synch up at 4000 rpm's when you did the TBS?

Brian, the vibes are bad at those RPMs in 6th gear, and I can't seem to accelerate out of it. I also noticed excess roughness at lower RPMs in 6th gear - around 3200 rpms -- as that seemed like a lugging-type of load to the engine.

don't use 6th unless the situation allows higher speeds/rpms. mine is silky smooth in 6th at those levels and not very buzzy otherwise.

gotta get to the bottom of this.

+1

With an RT, running at 4k in 6th (80mph) the bike should hum along and be smoooooth.

When TBSing mine, and being anal and all, I do a TBS synch (using a Morgan Carbtune)from just off idle, all the way up to 5k.

I then hold it in place every 1k rpm for a few secs (using my Throttlemeister) checking for a steady balance. I never use 6th unless I am doing 70 or more.

Hi Bud,

From what has raised it's head so far, I'd still be inclined to look for something that is not bolted down tightly or is bolted up such that you are transferring engine vibes to frame.

It may well be worth taking the tupperware off and working your way around the beast to see if something has moved.

Andy

I never use 6th unless I am doing 70 or more.

Seriously? You ride that fast????

Nah! Only with you.... LOL !

Hi Montana I also own a 2004 RT also. I didn't read all of what everyone said so if I repeat sorry. I read what you've done in your 1st description of the problem. My bike has 82k miles. My average RPM range is 3.5krpm to 4.5krpm. I get a little vibration at 4krpm and then it goes smooth to 4.3krpm. Around 4.5krpm I get a little stronger vibration like one cylinder is a little stronger than the other and that goes away around 4.6k rpm. If you don't have any new noises check compression like someone said earlier. After that check the rocker arm end play. I've seen end play where if you push up on the rocker arm the feeler gauge falls out after the 600 mile dealer service. If the end play is good I adjust my valves using the Von Baden(Ithink thats his name) technique using one feeler gauge cut so it will fit to adjust both the intakes at the same time and exhausts at the same time. I like the technique.

http://advwisdom.hogranch.com/Wisdom/JVB%20valve%20adjust.html

Hay Bud

This is a long shot, but since your bike is getting up in miles, and my instinct says this is a fuel system/TB balance issue; what if your throttle body butterfly shaft is getting worn? This could change your fuel/air mixture and cause rough engine running conditions at some rpm's. It might also cause a hunting/surging condition at the same time.

Check the throttle body shaft where the cable is connected to the shaft at the "pulley". Move the shaft up/down with the cable loose and feel for looseness in the shaft.

As I say, a long shot but worth the check.

Mike, I just checked the TB's pulley cam. They both move a bit in and out, the right side seems a bit looser than the left, but I'm not sensing much (if any) up and down movement, only in and out.

Is this normal or does it indicate wear? If it's problematic, what's the fix? New TBs?

Bud

Movement up and down is a problem. I don't know about back and forth. Make sure you twist the throttle open some at the TB to loosen the cable, then try the up/down check. As the shaft & sleeve get worn, you'll feel movement. This wear allows air in and changes the mixture. The reason I thought about this issue is that mine are really bad and I'm getting vibration and out of tune conditions at throttle.

Replace or repair: kits are available from Bing in KS, and I just ordered a kit plus 50 bushings (minumum order, bushings not in the kit)

See: http://bmwsporttouring.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=605071#Post605071

and: http://bmwsporttouring.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=603094#Post603094

I just checked the TB's pulley cam. They both move a bit in and out, the right side seems a bit looser than the left, but I'm not sensing much (if any) up and down movement, only in and out.

 

Is this normal or does it indicate wear? If it's problematic, what's the fix? New TBs?

Evening MontanaBud

Keep in mind that any leaks at the TB shafts or bushings are small leaks. So as the throttles are opened the percentage of air that can enter there is lower and lower.

When the throttles are opened to road load 4,000 RPMs the major air flow is in through the open throttle plates and that also means the vacuum or pressure delta is also much lower across the throttle area.

So in a nut shell if you have vacuum leaks that you can feel at 4K you will have MAJOR leaks and runability problems at 2K & 3K.

I don't know if people still do this but, rubbing alcohol dripped on the vacuum leak would choke the engine down. I THINK some also use WD40. Wd40 would just make it smoke.

Bump. Anybody know the end result here? I am having the same issue.

Good friend, fellow rider has a `04 R1150r that has a similar vibration issue.

All is well up to and including 3200 rpm, then it sounds as if all hell has broken loose, the sound and vibration makes the M/C a near unbearable ride. A very hammer like sensation.

Checked all of the usual things (so far), TB balance, tire balance etc.

From cold, started engine, let it warm. Placed hand on top of tank, revved engine to 3,000 then up to 4,000 rpm. No unusual vibration other than the tingle of expected engine operation.

Some questions for the group:

Are the auxiliary (lower ) spark plugs in operation a low speed, say, at less than 3k revs or do they begin operation at 3k + rpm?

Better yet at what rpm do they function at?  Constant? Under load only? High? Low? References I have seen don't seem to answer/cover this question.

Testing the function of the igniter caps: is this done the old fashioned way, that is, remove igniter push old sparkplug  in the igniter, ground sparkplug and look for spark?

Reason for this Q is in some older Asian bikes, it was possible to destroy the CDI box (don't ask how I know) if it was not tested correctly.

Also could vibes be a driveline/driveshaft issue.

To reiterate, bike is a joy to ride below 3,200 rpm, then it is a REAL pita after that. Continues to run much beyond legal speeds, have seen 45400 on the tach with a quick glance.

am new to this forum, reading what other's have writ, seems as  this group is more technically inclined than other's I belong to.

No joke here, all comments and replies are appreciated.

Gary, aka RBGary     

29 minutes ago, RBGary said:

Good friend, fellow rider has a `04 R1150r that has a similar vibration issue.

 

All is well up to and including 3200 rpm, then it sounds as if all hell has broken loose, the sound and vibration makes the M/C a near unbearable ride. A very hammer like sensation.

 

Checked all of the usual things (so far), TB balance, tire balance etc.

 

From cold, started engine, let it warm. Placed hand on top of tank, revved engine to 3,000 then up to 4,000 rpm. No unusual vibration other than the tingle of expected engine operation.

 

Some questions for the group:

 

Are the auxiliary (lower ) spark plugs in operation a low speed, say, at less than 3k revs or do they begin operation at 3k + rpm?

 

Better yet at what rpm do they function at?  Constant? Under load only? High? Low? References I have seen don't seem to answer/cover this question.

 

Testing the function of the igniter caps: is this done the old fashioned way, that is, remove igniter push old sparkplug  in the igniter, ground sparkplug and look for spark?

 

Reason for this Q is in some older Asian bikes, it was possible to destroy the CDI box (don't ask how I know) if it was not tested correctly.

 

Also could vibes be a driveline/driveshaft issue.

 

To reiterate, bike is a joy to ride below 3,200 rpm, then it is a REAL pita after that. Continues to run much beyond legal speeds, have seen 45400 on the tach with a quick glance.

am new to this forum, reading what other's have writ, seems as  this group is more technically inclined than other's I belong to.

 

No joke here, all comments and replies are appreciated.

 

Gary, aka RBGary     

Afternoon Gary

Difficult to tell you much as we can't hear, feel or ride that motorcycle over the Internet.  

The BMW 1100/1150 engine is a basically balanced BOXER design, but seeing as each piston has it's own crankshaft journal the pistons are not directly across from each other so up in the 4,000 RPM & up range they can have a pretty pronounced BOXER  buzz. This buzz is worse on some engines & it effects some riders more that others. Some riders never seem to notice it & others are bothered by it every time they ride the darn things.

On the twin spark BMW 1150 both upper & lower spark plugs stay in sync & spark all the way through the RPM range.   On the later 1200 engines BMW used a different spark curve for the lower spark plugs that retarded the spark  enough at higher RPMs to basically remove the lowers from doing anything at high RPM's. 

Testing the function of the igniter caps?-- Are you referring to the upper coils on the spark plugs? If so then those are very difficult to test. You can put a known good spark plug in the coil then test for a nice snappy bluish colored spark but that just shows if a total failure. Those upper coils can spark OK under no compression at engine cranking RPM's but still not produce enough spark at high RPM under heavy road-load.  

Those coils also have an isolated secondary so no good way to test them with an ohmmeter.  (they typically break down internally with the secondary arcing internally to the RFI shield). 

Is the vibration still there at 4000+ in second or third gear? (this can help tell engine related or drivetrain related). 

You might want to check for a loose clutch disk on the transmission input shaft splines (worn input or clutch hub splines). This can allow the clutch disk to run off-center & give an out-of-balance issue. Best way to check this (without a teardown) is to remove the starter, tie the clutch lever to the handlebar grip, then use a sharp pointed wire or awl to see how much the clutch disk can be rotated before moving the input shaft. 

I agree with your first statement.

Tiny bio on me, at this time my ride is  a 2050 1250 shift cam RT . Owned one of the first oil heads (2001?) years ago along with a couple of airheads.

As I stated in my note, this vibration, buzz, is way beyond the rocking couple I experienced when I road a 1958 BMW. Can't remember the model, do recall it had a Earles fork suspension it.

Friend is on his way at this moment to a mechanic he regards as being very good.

I have ridden/owned  many M/C's, name the make, I have been on it, feel I am fairly competent at diagnosing problems. This one though, it has me stumped.

Bike is fun to ride up to 3200 r's approx, in top gear 65-70 mph, above that it shakes like the proverbial dog that has eaten too many peaches, pits and all, and is trying to rid himself of the pits.

Friend bought this bike used, stored and well cared for, he and I are on the trail to figure out what in the H could be the problem.

Thank you for you  input and quick reply, I will post as to our findings "down the road" so to speak.

Gary  

4 minutes ago, RBGary said:

I agree with your first statement.

 

Tiny bio on me, at this time my ride is  a 2050 1250 shift cam RT . Owned one of the first oil heads (2001?) years ago along with a couple of airheads.

 

As I stated in my note, this vibration, buzz, is way beyond the rocking couple I experienced when I road a 1958 BMW. Can't remember the model, do recall it had a Earles fork suspension it.

 

Friend is on his way at this moment to a mechanic he regards as being very good.

 

I have ridden/owned  many M/C's, name the make, I have been on it, feel I am fairly competent at diagnosing problems. This one though, it has me stumped.

 

Bike is fun to ride up to 3200 r's approx, in top gear 65-70 mph, above that it shakes like the proverbial dog that has eaten too many peaches, pits and all, and is trying to rid himself of the pits.

 

Friend bought this bike used, stored and well cared for, he and I are on the trail to figure out what in the H could be the problem.

 

Thank you for you  input and quick reply, I will post as to our findings "down the road" so to speak.

 

Gary  

 

 

Afternoon Gary

Can you or your friend tell if the shake is a lower frequency (like wheel rotational speed), or much higher frequency (like engine RPM), or  more mid range frequency (like drive shaft speed)? 

Wheels and tires have been checked for balance and found to be okay.

Its a mystery to he and I that everything is good, then, over 3,200 r's, 60-70 mph, its excessively buzzy, noisy, beyond belief. 

He is on the way to his mechanic, I will report what the two of them find.

thank you for you input.

I will post something of interest tomorrow.

Gary

18 hours ago, RBGary said:

Wheels and tires have been checked for balance and found to be okay.

Its a mystery to he and I that everything is good, then, over 3,200 r's, 60-70 mph, its excessively buzzy, noisy, beyond belief. 

He is on the way to his mechanic, I will report what the two of them find.

thank you for you input.

I will post something of interest tomorrow.

Gary

Afternoon Gary

Wheels and tires have been checked for balance and found to be okay.-- That accounts for the balance but doesn't do anything for a tire force variation issue, or a tire construction problem. 

Its a mystery to he and I that everything is good, then, over 3,200 r's, 60-70 mph, its excessively buzzy, noisy, beyond belief. -- This can be tracked somewhat by relating the disturbance to the what is spinning at that RPM (frequency), probably won't get a lower frequency shake from a 4000 RPM engine. Or get a higher frequency heavy buzz from a lower RPM wheel.  

6 hours ago, dirtrider said:

Is the vibration still there at 4000+ in second or third gear? (this can help tell engine related or drivetrain related). 

I didn't see a clear answer to this question.......I could have missed it.

At this point, I'm thinking driveshaft or u-joint, but really need to know if it happens in all gears at the higher RPMs.

To all on the forum:

The owner and I have it nailed down to repetitive backfire in the catalytic converter chamber which is giving a metallic sound.

He is installing some aftermarket mods, one to fatten up the mixture at and just off idle, and has ordered a custom curve chip for the motronic ecu.

Will continue to inform the forum as how these mods work one way or the other.

RB Gary.

PS;

Look up "Booster Plug" on the web that is mod#1

9 minutes ago, RBGary said:

To all on the forum:

The owner and I have it nailed down to repetitive backfire in the catalytic converter chamber which is giving a metallic sound.

He is installing some aftermarket mods, one to RBGary, and has ordered a custom curve chip for the motronic ecu.

Will continue to inform the forum as how these mods work one way or the other.

RB Gary.

PS;

Look up "Booster Plug" on the web that is mod#1

 

Afternoon  RBGary

Tell him not to waste his money on a booster plug, those thing do NOTHING when running in closed loop fueling. 

If he is getting a post-firing in the catalytic converter then  find the reason why, don't try to band-aid it. (does it have a leaking exhaust valve or a pre-cat exhaust leak sucking in air on the off-stroke?)

I guess I don't understand why he is  trying to  " fatten up the mixture at and just off idle " when his problem is at 4000 RPM's (WAY above idle).  

4 minutes ago, dirtrider said:

Afternoon  RBGary

 

Tell him not to waste his money on a booster plug, those thing do NOTHING when running in closed loop fueling. 

 

If he is getting a post-firing in the catalytic converter then  find the reason why, don't try to band-aid it. (does it have a leaking exhaust valve or a pre-cat exhaust leak sucking in air on the off-stroke?)

 

I guess I don't understand why he is  trying to  " fatten up the mixture at and just off idle " when his problem is at 4000 RPM's (WAY above idle).  

Thanks of the quick reply, I'll pass this on to him.

RB Gary 

Updating the forum on this vibration issue, it is still a mystery, owner is working  on it.

RB Gary

31 minutes ago, RBGary said:

Updating the forum on this vibration issue, it is still a mystery, owner is working  on it.

RB Gary

Afternoon  RBGary

It sounds like he is randomly sticking a knife in the grass trying to hit an unseen  snake.

He first needs to define exactly what he is looking for ?  A chart or list can greatly help here.

He needs to define the EXACT RPM that it starts at, the RPM that it stops at (if it even stops at higher RPMs & that needs to be noted if if doesn't stop).

He needs to define the throttle openings that it starts & stops at. Then rate the severity at different RPMs. 

He needs to positively define if it is road speed related, or engine RPM related and/or engine load related. 

He needs to define if it is better or worse cold vs hot &  where it is the same or varies? 

Personally I also like to run them out to top speed for a mile or so to see if it can maintain 125+ mph (some can't or are afraid to do this so it is very optional based on local environment & riders skill).

Once he knows the what, the where & what causes (or effects)  the problem then maybe he can define an area to look into. If that doesn't help then he needs to go back to the basics like compression test, leak-down test, fuel flow test, ignition component testing (or substitution), exhaust backpressure testing (or ride with cat & muffler removed). 

I wonder if the the Hall effect sensor could be acting up? Put that on your check list.