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Are oilheads more buzzy

roostershooter

motorcycle cowboy
As the miles add up? My '04 RT has 43k on the clock. This is my first BMW and it seems like it's more buzzy in the seat and grips than when I bought it 8 years ago. Do they get more buzzy or am I more sensitive?
 
Typically they get LESS buzzy after they're broken in. At some specific RPM there can be specific imbalances that show up, but between 3500 and 6000 RPM, it ought to be pretty smooth. Not like glass, 'coz it's only 2 cylinders, but not buzzy. Something is asking for a look... If you can isolate at what RPM, what actual road speed, with or without the clutch pulled, what gear, what side (right rear may portend a driveline failure), etc., that should give some clues.
 
My 1997 R1100RT gets "buzzy" as well, but, not all the time.

I live in a place where a day over 75F gets kids out trying to cook eggs on the pavement. Too hot for street hockey I guess. Still a nice day but rather rare. When the temps get above 75F, wow, my riding lawn mower seems faster and run better. I get a very distinct "buzz" at about 3200 to about 3800. It doesn't matter what gear or the road type.

Below 75F, just even a few degrees, no buzz, horsepower to spare, shifts like an automatic and no "rattle" from the cam chain tensioners.

I guess what I'm saying is, move to Canada and you won't have a problem?

I'm looking forward to seeing the weigh in on this string.
 
FYI- the cam chain upgrade is not a Tom Cutter item, he just sells the OEM upgraded parts as an available kit.

Upgrading to newer unit it might address the buzz issue, but I tend to doubt it, especially as you say you don't hear it at startup. Easy to check if yours has already been done or not. Earlier design used a 17mm head bolt, new one is 15mm.
 
43K is still pretty low miles.

when's the last time you did a valve adjustment and a TBS?

What he said, adjust the simple stuff first. TB Sync, always smoothed the vibs. Also surprisingly so did addition of a Techlusion, I actually was surprised at the difference, so I disconnected and reconnected the device to verify that it did smooth it out.
 
Buzz

Another source (don't ask how I know) is related to wheel damage. I'm guessing that in my case, the cast aluminum wheels are just a little more subject to damage when hitting potholes, railroad crossings, asphalt grinder joints, etc. The damage may not be visible, but just a small amount can add to buzz in the handlebars and seat, and it doesn't matter that the wheels/tires are balanced, you will still get the buzz.
 
On my Oil Heads, I've had 5, some did this more than others, I could tell if I filled the oil up past the mid way on the sight glass because of increased vibration. If the oil showed up near the top of the sight glass, I knew this before I ever looked at the sight glass from the increased vibration through my pegs and bars. If I ran with the oil between the bottom of the window and the mid point I had less vibration.

I also had more vibration if my TPS was not set correctly.
 
[QUOTE I get a very distinct "buzz" at about 3200 to about 3800. It doesn't matter what gear or the road type.

Below 75F, just even a few degrees, no buzz, horsepower to spare, shifts like an automatic and no "rattle" from the cam chain tensioners.

I too, feel my 96 1100 is more "buzzy" than I thought it would be. I have noticed that when first started, when the engine is still relatively cold, it runs a lot smoother...really nice. Once warmed up, it's noticeably less so. I assume that is because the fuel system is then running it a lot leaner. I also feel that at lower speeds, but higher rpms (3200-3800) the engine seems to be rougher, straining, so to speak. Once at highway speeds, I don't notice it. I have solved this by usually running at about 3000 rpm when not on the expressway. Then it is fine. I was told on this forum that the 1150s have a conterbalancer shaft in the engine that probably solves a lot of this problem. I would almost trade my trusty 1100 to get that, and the 6th gear. But I like the 1100, and I've just learned to live with the less than perfect smoothness. It is, after all, a twin, as has been stated. I can't have everything. And it's really easy to work on.
 
WOW, I'm loving this stuff!!!!

On my Oil Heads, I've had 5, some did this more than others, I could tell if I filled the oil up past the mid way on the sight glass because of increased vibration. If the oil showed up near the top of the sight glass, I knew this before I ever looked at the sight glass from the increased vibration through my pegs and bars. If I ran with the oil between the bottom of the window and the mid point I had less vibration.

I also had more vibration if my TPS was not set correctly.

The oil level thing, you bet and I can't rationalize why. Me bad one day, a bit too enthusiastic and I over-filled my own R1100RT by about a cup and got a buzz. I looked for a reason for a long time and didn't think about the last thing I did to make a change in the bike, the damn oil change and over-filling it. Next oil change, more careful, nice rainy afternoon and the right oil volume, buzz is gone. Explain that to me with with an Excel spreadsheet.

jconway607, we have lots of days below 75F and last I knew, we still like our neighbours (that's the Canadian spelling version). Move here and avoid having to shell out the coin on another bike that has it's own issues. 6 gears would be nice though.

I have an '81 KZ440 LTD that was a basket case. In cooler weather, the little girl is massive fun. A little warmer and it gets harder to start. The choke even needs to stay on longer. It "fuel loads" on one cylinder on start and takes a block or two to really want to run nice. I have done everything two or three times and the only conclusion is that I may have a valve stem that changes shape a bit. Yeah, that's a stretch but I don't have a wideband oxygen sensor to worry about. I don't worry about fuel economy because it's fun to ride.

Ambient air temp has always been a given that it affects an engine and sometimes, big league effect. Just ask the long haul guys that spend thousands on wrapping their intakes and exhaust with blankets. Keep the air cool going in and cool going out, and you can create a different animal.
 
What he said, adjust the simple stuff first. TB Sync, always smoothed the vibs. Also surprisingly so did addition of a Techlusion, I actually was surprised at the difference, so I disconnected and reconnected the device to verify that it did smooth it out.
Not so surprising that the Techlusion would do that.

Vibrations and buzz can come from several sources which others have commented on. Power/torque imbalance buzz can sometimes be improved by an AFR (air fuel ratio) balance which means balancing the air side to side, and the fuel side to side. BMW solved the fuel balance problems on the R1200 Hexhead and Camhead with dual O2 sensors and independent cylinder software Adaptation.

On R1100s and R1150s, a TB balance done well will usually result in balanced AFRs. But if the injectors are mismatched through aging or otherwise, no amount of TB balancing will fix the problem. When you add fuel, as with a Techlusion, you can get to the point where you've added enough to consume all air in the cylinder charge. That will get the power/torque back in balance.

Although the Techlusion has been around a while it has three drawbacks: it's an Open Loop solution, the Motronic shifts to limp home fueling pattern and it has four adjustments, none of which have a specific, known effect. Now there are two lambda shift devices available that add fuel Closed Loop, with only one adjustment, and in specific, known amounts: Innovate Motorsports LC-1 and nightrider's BMW-AF-XIED.
 
I also feel that at lower speeds, but higher rpms (3200-3800) the engine seems to be rougher, straining, so to speak. Once at highway speeds, I don't notice it. I have solved this by usually running at about 3000 rpm when not on the expressway. Then it is fine. I was told on this forum that the 1150s have a conterbalancer shaft in the engine that probably solves a lot of this problem. I would almost trade my trusty 1100 to get that, and the 6th gear. But I like the 1100, and I've just learned to live with the less than perfect smoothness. It is, after all, a twin, as has been stated. I can't have everything. And it's really easy to work on.

that sounds like your cables are not correctly synched for higher (normal) rpm running (although not being familiar with the 1100R cable system, I could be mistaken on that). Synch the BBS at idle, cables at 4K or so.
 
I wonder if faulty stick coils could be the problem? Aside from the buzziness, my symptoms are a very rough idle, (to the point of adding throttle at stops) diminished fuel economy and in the higher rpm's the engine seems to "load up" and kinda bog down as I accelerate to the higher rpm range. It's not very pronounced but I know it's there. I am confident that the valves and TB are in good order. I don't really want to gamble prices for new stick coils at this time without having some indication that they were bad.
 
A few weeks late with this update but, I did go ahead and order the stick coils. After installing them, I am simply amazed at the marked improvement in performance. No more buzzy seat, pegs or hand grips. Power has increased, mpg's have improved, idle is smooth and silky, and power roll on is simply awesome. My source.....http://euromotoelectrics.com
 
On a running multi-cylinder internal combustion engine, vibration comes from only two basic causes:
1. Mechanical imbalance
2. Combustion imbalance

There is some inherent slight mechanical imbalance. But that is unlikely to change much over time unless you have internal transmission problems or driveline universal joint problems. If you have an oiling problem on one cylinder a heavy build up of carbon on only one piston top can cause a buzzy vibration.

Most vibration changes over time however are due to combustion imbalance. Throttle synch matches air flow (absent other obstructions), clean injectors match fuel flow, valve adjustment is critical, good spark plugs are important, etc. A significant difference in compression could be a factor.

Bottom line is that the bike probably needs a meticulous tune-up.

Edit: Ooops! I ought to look at the end of a thread before adding comments.

p.s. I hate stick coils!
 
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Nice description Paul.

You can further reduce the fueling imbalance by richening the mixture. The way this happens is that as you richen the mixture, the small amount of unburned O2 in a stock motor gets consumed. Once the O2 has been used up, any excess fuel in the richer of the two cylinders doesn't add power. Bottom line is that the power produced by each cylinder is then affected mostly by the air balance.

RB

P.S. I just replaced my stick coils too. I was very surprised at the improvements in starting and running.
 
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