WELL GUYS I BOUGHT A 1984 R80RT BMW WITH A SIDECAR 23K ON IT. THE GUY I GOT IT FROM TOOK THE SIDECAR OFF LAST YEAR SO I PUT IT ON.
ONE THING NOW.. WHEN I LET GO OF THE BARS I GET A HORRIBLE HEAD SHAKE AND HAVE TO GRAB THE BARS.. THEY GO BACK AND FOURTH REAL BAD...
I FOLLOWED THE INSTRUCTIONS FOR TOE IN AND OUT AND ALL THAT AND GOT IT PRETTY GOOD. THE BIKE IS SMOOTH UP TO 70MPH.
Originally written by JTSKIR222 on 7/9/2007 5:17 PM
WELL GUYS I BOUGHT A 1984 R80RT BMW WITH A SIDECAR 23K ON IT. THE GUY I GOT IT FROM TOOK THE SIDECAR OFF LAST YEAR SO I PUT IT ON.
ONE THING NOW.. WHEN I LET GO OF THE BARS I GET A HORRIBLE HEAD SHAKE AND HAVE TO GRAB THE BARS.. THEY GO BACK AND FOURTH REAL BAD...
I FOLLOWED THE INSTRUCTIONS FOR TOE IN AND OUT AND ALL THAT AND GOT IT PRETTY GOOD. THE BIKE IS SMOOTH UP TO 70MPH.
This is going to sound like a smarta**ed answer, but DON'T LET GO OF THE HANDLEBARS! and stop shouting. A little headshake is normal, attributed to all the new weight off to one side. Some causes can be worn or loose steering head bearings, worn or loose swing arm bearings, sidecar too far forward, too much weight in the sidecar, etc. I had a HitchHiker on a Goldwing once. The body had three sets of mounting holes in the frame. I can't remember which way it was, forward or back, but at one extreme the shake was gone, at the opposite it was almost uncontrollable.
At what speed does this happen? At low speed it is a little dangerous but mostly annoying. At high speed its deadly. Can you accelerate through it? Is it controlable when it happens? My rig does this right at 20 mph. Once I get to 25 mph it goes away. I just keep my hands on the bars during this phase.
Does your BMW have a friction steering damper? Tighten it down if you have one.
Are the steering head bearings loose or worn? Tighten or replace them.
IT HAPPENS ONLY WHEN I TAKE MY HANDS OFF THE BARS..
SLOW OR FAST IT HAPPENS. AND IT GETS REAL BAD.
WHEN I HOLD ON NO PROBLEMS. WHEN I LOOSEN MY GRP I FEEL IT. WHEN I LET GO IT GOES NUTS AND I HAVE TO GRAB THE BARS HARD.
I WILL CHECK THE HEAD BEARINGS OUT.,
This is not abnormal to sidecars but things can be checked to possibly make it go away or help.
First off tighten the steering head bearing more tha spec for a solo bike.
Check all bearings as has already been mentioned.
Play with tire pressures some , especially in the front.
Check your spokes if you have them.
I you are running a lot of wheel lead reduce it.
If you are running a lot of toe in reduce it.
Check your mounts. The bike and sidecar shoudl be as one unit with no flex or movement.
Last resort install a damper.
Note that after you do some tweaking if the wobble is controlled easily by having your hands on the bars and if it is such that it goes way at a higher speed then a damper is going to be counterproductive in that it will make steering harder.
Note that if the wobble gets to where it is non existant with a hand on the bar and only appears when you let go of the bars then the best thing to do is just ride it.
Originally written by JTSKIR222 on 7/9/2007 8:27 PM
IT HAPPENS ONLY WHEN I TAKE MY HANDS OFF THE BARS..
SLOW OR FAST IT HAPPENS. AND IT GETS REAL BAD.
WHEN I HOLD ON NO PROBLEMS. WHEN I LOOSEN MY GRP I FEEL IT. WHEN I LET GO IT GOES NUTS AND I HAVE TO GRAB THE BARS HARD.
I WILL CHECK THE HEAD BEARINGS OUT.,
PLEASE!!!!!!!! dont shout! Use small letters in your replies.
Caps are only used to start sentences and for names....or to EMPHASIZE something.
Like Mike said..dont let go of the bars.... my K bike wiggles it's head when I shift from 1st to 2nd, around 15 MPH.then no more shaking all the way up to 130.
Bob Wrote:
>>....snip...my K bike wiggles it's head when I shift from 1st to 2nd, around 15 MPH.then no more shaking all the way up to 130.<<<
130? Not bad Bob I am impressed 🙂 You shoudl not have to leave for the RON DEE VOO very early this year!
Over the 4th there was a blurb on the news here about the state patrol stopping someone on a bike they'd caught doing 130. They failed to mention that it was a sidecar rig. Hey Bob, next time you're out this way stop by for a cup o' coffee!
Originally written by claude #3563 on 7/10/2007 7:34 AM
Bob Wrote:
>>....snip...my K bike wiggles it's head when I shift from 1st to 2nd, around 15 MPH.then no more shaking all the way up to 130.<<<130? Not bad Bob I am impressed 🙂 You shoudl not have to leave for the RON DEE VOO very early this year!
HEE HEE! 130!!!!! just kidding of course :o)
I was wondering who would comment on this statement.
actually it really doesnt wobble at all over 15,just when shifting to 2nd,[no damper] but the highest I've gone has been 90...fast enough for me and only to see about the power of the new K bike/has a lot left to go. the faster it goes the smoother the bike gets.
normal HWY speed for me is 65...80 on the 'states if I'm in a hurry.
It did wobble more until I tightened the newly installed head bearings after about 500 miles.
just the opposite of my airhead.
Originally written by Bob in Wis on 7/10/2007 7:40 AM
Originally written by claude #3563 on 7/10/2007 7:34 AM
Bob Wrote:
>>....snip...my K bike wiggles it's head when I shift from 1st to 2nd, around 15 MPH.then no more shaking all the way up to 130.<<<130? Not bad Bob I am impressed 🙂 You shoudl not have to leave for the RON DEE VOO very early this year!
Boy, I was also pretty impressed at 130 (LOL). I have had the Wing to just over 100 (per the GPS). Very stable at that speed, but would go much faster I don't think.
HEE HEE! 130!!!!! just kidding of course :o)
I was wondering who would comment on this statement.
actually it really doesnt wobble at all over 15,just when shifting to 2nd,[no damper] but the highest I've gone has been 90...fast enough for me and only to see about the power of the new K bike/has a lot left to go. the faster it goes the smoother the bike gets.
normal HWY speed for me is 65...80 on the 'states if I'm in a hurry.
It did wobble more until I tightened the newly installed head bearings after about 500 miles.just the opposite of my airhead.
Many of the Beemers also have very narrow handlebars which also exacerbates the problem of head shake control.
Okay, okay, it makes it worse. LOL
Lonnie
I tightened up the head bearings on mine, a little on the snug side, and found it no longer would self center. By self center, I mean the bike straightens up on it's own. I didn't like the feel of it one bit. I loosened them enough not to clunk, but no drag, and the bike handled much better. I think your problem could be tire wear, sidecar position or alignment, or maybe front disc drag. You mentioned your bike has been used for a solo. On a sidecar rig, the tires will square off. Until they do, this will also effect your handling.
Friends,
All sidecars tend to shake at very low speeds 20-30km
Its a physical effect you can read about in the translation of the german manual in the links section.
Thats the reason why allmost all rigs have a stearing damping by shock absorber or old style friction plates.
Might be your damping is out of function or too week.
For those friends who have problems with a normal stearing shock absorber you might ask a FESTO-pneumatics distributer they have a few types that adjust automaticly to the load.
High force and speed > high damping rate
low force and speed > low damping rate.
works perfect in many industrial production lines.
I am a little outdated on models but they have or make a model for every need.
Used them allways for dificult aplications.
Best luck
Sven Peter
Hi guys
my head shake is at all speeds.
i will check out all the suggestions this weekend on the bike.
my ural gear up has about zero head shake..
but again the factory put the car on and not me like this one....
peterm pan wrote:
>>All sidecars tend to shake at very low speeds 20-30km
Its a physical effect you can read about in the translation of the german manual in the links section.
Thats the reason why allmost all rigs have a stearing damping by shock absorber or old style friction plates..<<
'Tend to shake' and actually doing so are not one and the same.Fact is that Some do and some don't. I do not want to sound argumentative but to say that almost all rigs have a steering damper is simply not correct. We do all we can to alleviate the necessity of a damper and actually very few rigs that leave our shop need one. Some do but it is the exception and by far not the rule. Guess I am just a terrible salesman.
