The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: jakebass12 on August 15, 2012, 12:52:24 AM
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i finally got my bike running and went for a ride and hit some corners and it started doing a little wobble but when i straightened out it stopped. i thought it could be the tire pressure so i checked it and it was a little low so i put them to the right air pressure but the wobble still persists. so i was wondering what could cause it? i the only other thing i think it could be is the stock rear suspension.
any ideas and input are very appreciated
jake
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The "wobble", is it a head shake or does it feel like the back of the bike is wallowing around.
I think you mentioned that you were looking for shocks in an other thread......... might be a good place to start
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how old are the tires?
how old are the tubes?
exactly as he said, how about your shocks?
and are your tires balanced?
after those all check out then i would check your bearings
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What speed in the corners ?
I'd be looking at in order of quick easy checks to more involved:-
Tire pressures but not so much age as long as they are sound and not unevenly worn.
Play in the steering head bearings
Play in swinging arm bearings
Play in the wheel bearings
Rear shock damping
Front fork alignment (Stiction)
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Does it wobble when leaning in both directions? If it was stored on the sidestand for a long time with full tire pressure, you could have some flat spots to the left.
How tight is the front axle nut? Overtightening it could cause the striction mentioned above.
Are the preload adjusters on the rear shocks set to the same setting?
Overtightening the steering head bearings can also cause poor low speed handling.
Are the forks perfecly even in the top triple clamp? Do both your forks have the same amount and type of oil in them?
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the tires are new and i dont think they have tubes, but if they do there probably new too. and i dont think the tires are balanced. the tires have even wear and the wobble is at all speeds. and there is no play in the swing arm nor anything else. and both the forks are perfectly even in the clamps and the has the same amount and kind of oil in each. so it must be the old shocks?
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Well you covered most possibilities but the shocks would have to be diabolically worn to cause a wobble at All speeds.
Is this by any chance the first ride on the new tires ? Balance might. be an issue but then again not at All speeds. Are the tires properly mounted i.e. beads fully seated ?
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the tires still have the hair like things on them. and the tires were already mounted when i got the bike. i dont think the tires are balanced. there aren't any weights on the rims. and the shocks dont stak in place like if i grab and pull them back and forth they move.
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Have a look at the tire walls close to where they meet the rim. There should be a a guide line which should be concentric with the rim edge. It's there as a check that the bead has been properly seated. The other way to check is to spin the wheels on the centre stand and observe if there is any obvious run out.
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Contrary to popular belief, wheel bearings do wear out, causing wobble when angular forces are applied, as in cornering.
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and the shocks dont stak in place like if i grab and pull them back and forth they move.
Are your shock mounts tight?
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and the shocks dont stak in place like if i grab and pull them back and forth they move.
Are your shock mounts tight?
yes everything is tight.
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If you grab the springs on the shocks they will wiggle a bit. However, if you grab the top and bottom of the shocks and they move, it sounds like the bushings are worn out.
I've never seen that happen, but I can only imagine it would give some handling problems
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No the movement is only in the springs. I think that the tires not beingnbalanced is the issue.
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I suppose you ought to get the tires balanced and let us know how you make out then
Tire balace usually won't affect handling at low speeds, and there will almost certainly be pronounced speed ranges where vibration is worst. Tire imbalance will cause vibrations even when traveling in a straight line.
It's also possible somebody snapped or damaged a belt in the tire while mounting it, especially if the rubber was too cold or the first bead wasn't in the rim's center while slipping the second on.
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Agreed, Tires! I recently replaced mine and all my wobbling went away.
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I found my swingarm to be loose on the spindles.. I could move it back and forth 1/4"..
Turned out to be a nut stuck in the grease on the end of the adjuster keeping the bearings from being loaded....
Get ahold of that rear wheel and give it a good shaking.. If anything moves.... Look there...
John