Vibration

[fiolola]

Hello to everyone on this forum.Also new to older BMW bikes.Few month ago purchased an 84/R65 in a very good running condition.Most likely this has been asked and answered before.Is it normal that after 4k rpm engine vibration start creep in thru pegs? Other than gen light under 1,200 rpm when cold glowing, she is fantastic.Any advise would be appreciated.

[Luca]

The vibration is normal, but can be moved/minimized.

Provided the engine is properly tuned, check the torque on the engine mounts, and then experiment from there until most satisfied.  I just torqued mine at 50/45 ft-lbs front/rear, which is better than what they were at before (can't recall where I had them set, so I started over).  Every frame/engine combo is a little different, but those numbers should be a decent place to start.

I notice now that the vibration in the bars is nearly gone, while I can still feel it in the pegs.  My original footpeg rubbers are old and hard, so I'm considering replacing them to help damp things down a bit under foot.

There was also a product sold by Luftmeister to help dampen the vibration, though not everybody is a fan.  Just a few lines down is a thread on those.  It's titled: WTB Luftmeister vibration damper donuts

Welcome to the forum

[Bob_Roller]

I've had my '81 R65 since January, '81, when I first got the bike that vibration band was quite pronounced, it was like a switch was turned on, it came on that fast .

At 88,000 miles, I cannot detect any vibration band what so ever, don't know when it went away, maybe the engine is 'broken in' finally !!!!!

Or maybe I'm numb from the head down and can't feel it anymore !!!!

I had the Luftmeister vibration dampers on until they wore out, never saw any noticeable improvment when they were installed, my advice don't bother with them, it's a waste of time and money .
 
If you do decide to install some sort of damper, save the metal spacers that the dampers replace, they are not available anymore .

Your charging system is operating normal in regards to the 'GEN' light, also when you start the engine, before you hit the starter, make sure the red 'GEN' light is on, if it isn't, your charging system is not working, it's an important indicator of the charging system and easily overlooked if it doesn't come on .

[k_enn]

My experience with the vibration is similar to Bob's, but without bothering with dampers.   It used to be very pronounced between 4250 and 4750 rpm.  Just this past season, it has diminished to the point where it is barely noticeable.  Peace at last.   [smiley=smiley.gif]

k_enn

[wilcom]

Hello to everyone on this forum.Also new to older BMW bikes

What were you riding before the R65? Compared to a Japanese multi cylinder bike, Airheads are farm implements. I personally like to know whats going on via the sound and feel as opposed to the liquid smoothness of later model bikes
chug chug clunk clunk

[fiolola]

Well I took a long ride today and for my surprise cruising @ around 5k to 6k and she was singing a nice song.Hardly no vibration only on the lower rpm.Or maybe I'm getting use to.Present 2 wheeled 09 speed triple,84 R65, 84 vf 1100,81 kz 550 and 74 cb cafe racer.Will follow advises to minimize vibration.Overall she is a keeper.Thanks

[Bob_Roller]

The vibration band is only in the 4200-4700 rpm area, all bikes are diierent in this regards as to where it comes on and goes off .

[steve hawkins]

I can quite imagine the vibration getting less with time and that all bikes are different, with regard to exactly when the vibes come and go and to its intensity.  

I can also believe when you have had the bike some time, that most riders will automatically avoid the rev range and will either ride above it, or below it without even thinking about it.

As hinted to above, a tune up can also help, particularly a carb balance, which is the last thing you do, i.e. cold engine, tappets, static timing, dynamic timing, mixture followed by a ride and then a carb balance on a hot engine.

It would seem that this behavior might well be as a result of removal of mass from the flywheel, which happened in 1981, along with 5hp hike and a series of other weight saving measures.  But that is purely from anecdotal evidence that early pre-81 R65s do not seem suffer from it nearly as much.

Ho, hum.

Rev Light

[montmil]

Balancing throttle cables at approx 3500rpm goes a long way in eliminating most of the unwanted vibrations felt at cruising speeds.

Adjusting throttle cables is the last component in a full carburetor balance job.

[minitoo]

My R65 (10/82 build; 13,000 miles) had the typical 4200-4500 buzz.  It was really bad on a recent 2000 mile road trip carrying myself and about 50 pounds.  Everything tuned well and tweaking with motor mounts helped some but not enough and it had me looking for a better road bike.  

The bike was also scary in a cross wind so started looking at the suspension.  The rear shocks were totally toast.  No leaking just no rebound control.  I sprung for new rear Ikons and also Ikon fork springs.  Am happy to report that the bike has been transformed.  Handling is stiffer and controlled, ride height is up bit and... so that this isn't a thread hijack....the engine vibration is totally gone.  With my earplugs in I have to look down at the tach to see where I am and can cruise at or right through the dreaded buzz zone and not even be aware of it.

Don't know if this will help other bikes but I finally had something to share on this awesome site and had to chime in.