Chris in Santa Cruz, Stephen, Todd #389, Richard #230, Mark #403, Sean Casey #807
General Questions & Solutions
Q. I dropped my bike onto its side and the bars seem crooked. Anyone know a sure-fire way to check for bent bars? Or is it just if it looks right, it is right?
A1. It could be bent bars, but most likely the handlebar mounts just moved in their little rubber damping sockets. There are rubber mounts in between the handlebars and the top triple-clamp that can shift or move. It could also be the fork brace or finally the forks have moved with respect to the Triple Tree.
Q. Does anyone have a good tip on how to fix a bent handlebar? I dropped my CS and the RHS of the handlebar was slightly bent upward. BP316
A1. Get a long piece of pipe put it over the end of the bar and crank it (preferably with all the levers, grips, etc. off or you MIGHT damage them. Make sure you do it against the steering stops and someone else holds the bike. Don't over do it. Only for slightly bent bars. Kristian#562
A2. I am not sure about the
new models, but the 1997-2000 bikes handlebar clamps are rubber
mounted and relative loosely bolted to the upper triple clamp.
When the bars are hit the clamps will move and they can just be
twisted back into alignment. You should not have to tighten them,
unless you start to hear or feel a click when stopping or moving
the bike around with the handlebars. It can sound and feel like
loose steering head bearings, but is usually just loose bar
clamps. If you feel this click, then the clamps need to be
tightened slightly. This is done by loosening the jam nut that
holds the tension nut for the clamps in position and tightening
the nut above it. They are located under the triple clamp, where
the sun don't shine. Tighten the tension bolt no more than on
turn, re-tighten the jam nut and the clicking should disappear.
Checking if the Bars themselves are bent or they just moved.
Does anyone have a good tip on how to fix a bent handlebar? I
dropped my CS and the RHS of the handlebar was slightly bent
A. Get a long piece of pipe put it over the end of the bar and crank it (preferably with all the levers, grips, etc. off or you MIGHT damage them. Make sure you do it against the steering stops and someone else holds the bike. Don't over do it. Only for slightly bent bars. Kristian#562.
Q. Why are my Handlebars loose/wobbly or a bit off?
Because on the Classic there are Rubber Dampers (Part #4 in gif below) which can get sloppy over time. To fix it, undo the lock nut underneath the Triple Tree (One of the TWO #8's), do up the higher one, then redo the lock not. Do NOT over tighten, you are just tightening against the rubber!
For the Classic ONLY, (the GS does not have rubber dampers, so (a) the vibration feels like it is more and B, the Classic ones can go out of whack more easily.).
Problem: Everything looks straight, goes together smoothly...but the bars are askew. If you turn the bars in their mounts so they pointed the same way wa the tire, they are clearly not aligned with the triple clamp.
Forks twisted with respect to the Fork Clamps.
Highly unlikely but you will need to get at the Fork Clamps (Upper, Lower), undo them (one at a time) and realign the forks with respect to the wheel, triple tree and handlebars.
Unless you have really bent the main frame, try this:
If your twisted forks is slightly less serious (and this should work for 85% of the cases) just remove the front wheel, loosen the triple clamp fasteners, re-install and re-tighten, everything.
Note! Stroking the forks up and down prior to tightening the front wheel!
Most of the "mis-alignment" from a low speed dump is just "twisting" of straight components. By loosening all of the fasteners, these parts are allowed to "relax" and assume their proper alignment.
I would even recommend this procedure to anyone who rides a good bit "off-road" for any length of time. These parts aren't welded on. They move. Give them a chance to "move back".
Front Suspension FAQ
BradG#1002 & Kristian#562
This simple FAQ provides some tips and
suggestions for what to do if you think your front suspension may be damaged.
Refer also the Steering FAQ
After a recent crash I seem to have tweaked the forks. Any tips on checking them out?
A: If the crash was minor or you think the affect on the forks was small then it may just be that the front suspension assembly is just temporarily "pushed" out of alignment. There is some flexibility in the assembly and the fork to triple clamp connection can twist and stick out of alignment. The trick is to support the bike on a stand and loosen up the triple clamp to fork connections. This will allow the assembly to come back to it's normal un-flexed state. You can loosen the fork brace and axle as well but most of the problem is going to be in the triple clamps area. By loosen we don't mean so much so that everything falls off the bike, just enough to allow for some movement. You can loosen just one side to help prevent the forks from sliding down. Gently working the assembly by moving the handlebars back and forth while someone restrains the front wheel can help. Tighten up (make sure the forks have not slid down out of the triple clamps) just he upper triple clamp and make the front wheel secure then sit on the bike and work the forks up and down. Now tighten up the lower triple clamp and check the alignment. Hopefully your problem is solved. If things still look wrong and you're using the handlebars as a reference it may be the handlebars are bent.
If you are still concerned you have a problem then one of the forks could be bent. This is going to require that you do a bit more. One easy check is to remove the front wheel, fork brace and fork cap to allow you to freely slide the fork tubes up and down independently (with no spring resistance). If you feel any binding as you move the lower slider up and down (do it slowly if you have oil in them) then something is bent and you'll want to have your dealer or other professional take over. Tubes can be straightened but you may want to check the costs of repair versus replace to be sure it is worth the effort. The Official BMW manual describes the process of how to measure a fork tube for straightness. It requires some tools you may not have. If you have a large flat surface (like a thick marble or granite table) you can try rolling the tube to look for bends.
NOTE: This is a fairly simple but involved process and it deals with a major structure on the bike. The information provided here is meant only as a general guide in the absence of a full FAQ text.
One company that can provide assistance is Forks by Frank.
Another is http://www.motorcycleframeman.com/. The Frame Man in Sacramento straightened both fork tubes, the top clamp and the triple tree for $148 including return shipping for a '97 Classic. Flash #412 (CO)
If the stressed parts (ed. fork tubes) are Magnifluxed (tm), any subsurface hairline cracks in them will show up. Any good speed shop should know where to get this done in your area. - Flash #412
If you remove both fork legs and measure the distance between the tubes while they're in the yoke, it should be the same at any point between the yoke and the bottom. Now rotate one tube 90 degrees and repeat. Repeat until you have rotated that tube all the way around. Repeat for the other tube. If they measure straight, they're straight enough. It is quite possible to bend a fork brace with a twisting motion that is within the elastic capabilities of the tubes themselves. - Flash #412
Here is a Check List for inspecting a damaged front end. Provided by mtiberio
With the wheel still mounted, spin the wheel. is it bent? yes, have rim straightened if not too bad, or replaced. not bent? with the wheel removed, stick your fingers in the bearings and turn, is there roughness in the bearings? yes, replace them. no? go to step 2
Remove the front axel. using a large straight edge (level, vernier calliper, etc), and/or possibly a piece of glass, and any other means at your disposal determine if its bent. yes? straighten or replace, now go on.
Remove forks from triple clamps (after removing calliper, fender, etc). Holding the fork slider fast, and using a run out gauge (dial indicator or eyeball), turn the tube inside the slider, and look for any run out at the far end from the axel (top). if you have more than 5 or 10 thou, think about straightening/replacing. you can straighten bent tubes if they are just bent, and not kinked, creased, wrinkled, etc.
Turn the triple clamp in the steering head and feel for roughness or notchiness. If any replace the lower bearing at the least.
Find a straight section of the tubes if possible (if you pull them from the sliders, the section that was originally down in the slider is usually straight cause you were probably braking and close to bottomed at the moment of impact), and try and re-insert it into the triple clamp, do the same for the other side. If the tubes go up with no binding, then the clamps are probably straight, but check for parallelism between the upper and lower by eye as well. if not straighten or replace.
ST with BMW Handguards Hits Fairing
I have an ST with the BMW handguards. I also
have a windshield. The previous owner modified the windshield by
cutting semicircular portions out of each side right where the
handguards would hit. Works well, was neatly done and allows me
to lock the bars. I like the handguards, even if it is a
"street" bike. I don't have heated grips and those
guards really knock a lot of wind-chill and rain off my hands.
What can I do.?
I had to switch to the "touring handlebar" which is a bit wider. Of course they don't mention it when you buy the handguards. You have to buy what they call "the touring kit" (Tall windshield, wider handlebars and handguards).
Bike Steering Oddly
Q. My recently acquired '97 feels as though it is falling into turns, especially left handers. I did note the front Trail Wing is showing cupping and edge wear, but is that the cause or the result? I can't see anything else visually that would cause this effect.
Before you go Changing your Steering Head
Bearings note this
is typical of worn tires. Be sure to check the tire air
pressure. I recommend at least 34 pounds in the front and
36 to 38 in the rear." Richard #230. Refer the Tyre FAQ for more details on Tyre
Check your Fork Fluid Level Fork Oil Change FAQ, particularly if you have just undone a Lowering Kit. Wobble problem sorted: Re my posting "Today's problem" about a weave which happened at motorway speeds and could be provoked by pulling the bars quickly. Re-greasing the steering head bearings made a difference although the wobble could still be brought on at higher speeds. Then I went to change the fork oil and found 500ml in each leg, when there should be 600ml. As I've fitted a lowering kit each leg now has 650ml and the problem is cured. Thanks to everyone who gave advice. Ed UK.
Q. Won't corner? Don't know if you have found this. My bike wont corner!? Its a battle to throw it into a corner, darn thing wants to stand up all the time. Wondering if it is a suspension setup (front is soft), the tyres (std Bridgestone). It's the F650GS 01 mod.
CHECK YOUR TIRE PRESSURES!
The common cause for that is too much front end trail. The fix is raising the rear of the bike, which can be done with rear shock spring preload or heavier spring. Advrider
Tires are definitely a part of the equation, but you may have to change to find out. Had a mate look at the bike, he taught me how front and rear tyres wear and change bike handling characteristics. Its just got 10,000 k's on it and he commented on the large flat spot on the rear tyre (still legal). He said it will fight the corner until it rolls past the flat spot and then will want to lay over. The front tyre is wearing to a point (kinda) and wants to roll side to side, so when the bike corners, the front wants to corner, the back doesn't, or so the theory goes. I will try and wind up the spring preload on the back also. Might not defeat this characteristic until I change tyres. Advrider
Steering Head bearings ? I have the same problem on my 1997 F650ST and it has "notches" one cm to the right and left of center. It has 18000 miles on it now and the SHB problems just started a couple of weeks ago. I've found attacking the corners MX style helps Not that I've ever MX'd, but sit close to the tank, lean forward, arms wide, relaxed shoulders and arms and launch a full on attack. Left turns are worse than right and combination turns which are right then left are just murder. Advrider
Q. Fall Off Steering. I ride the F650GSPD. I'm not very happy with it for
one reason and maybe its just me. It seems like when I'm
turning at slow speeds it feels like all of a sudden the
steering wants to just keep going over.
I have actually dumped the bike when trying to turn a slow speeds. Now, I am so nervous that I am afraid to make even a moderate u-turn at slow speeds. when I ride around on Mike's 1150GS it feels just fine even though it is a larger bike. The bike started out as our son's and that is how I ended up with it. Mike lowered it a good 2" in the rear with a Koubalink thingy and then he did moved the forks up in the clamp about 1". Mike thinks this might have enhanced an already loose steering. (what he calls a nimble steering). Does anybody feel the way I do about the steering. I am ordering up 1" links and will leave the forks up in the 1" position, and see what happens?
As an experiment, increase the preload on the rear shock spring to maximum and ride the bike: don't mind the harsh ride, just feel the steering. If the tendency you dislike is improved or gone, you'll know that the cause is the rear of the bike being too low (or the front being too high). It sounds like when Mike lowered the rear 2" and lowered the front 1", fork rake and trail were increased, which causes the bike to be more stable in a straight line (resists front wheel deflection) but does cause that annoying "over-center" effect in turns. To fix it, you're going to have to level the bike out. Mully on Advrider.
It really does sound like you altered the steering geometry when you lowered the bike. Reducing the the trail is what we do purposely to make a sidecar rig steer more easily; if you take a the sidecar off a bike setup for hack work, it behaves exactly as you describe. It feels very unstable in the corners, as if you get to a certain point and it just wants to flop over. Sometimes different profile tires can cause or correct this. Try a taller tire on the rear or a low profile on the front, if you have some lying around and feel like experimenting while you are waiting for new links.
Try lowering the forks to 2" in the clamps and see if that corrects it: don't leave them that way, just do it as a test - they could bottom over a heavy bump. If that's the fix for the steering, then you either need to lower the front forks with spacers under the damper rods, or go back to the 1" rear links to balance it out. Lemme know and we'll discuss where to go from there. Mully on Advrider.
I don't think it's a matter of altered steering geometry or wrong spring preload. It's just the steering geometry of the bike: It does that. Cal BMW has F650GSs as their loaner bikes. They have standard setups, of course. Whenever I ride one, I get precisely that feeling: it wants to flop into turns. I even mentioned this to other riders at the dirt clinic back in February or so, and they agreed that they do that.
Q. What are the Common Causes of Weaving?
Luggage. My missus's F650GS was having problems tracking straight. On the weekend on autobahn up to German World MotoX round doing over 160km/h it was definitely weaving - we'd thought we'd cured it with front tyre pressure to 2.3bar - those bloody Bridgestone Trailwings are still going in favour of Tourances!! But then on the way back all her luggage was in my topcase and on my bike and the weave wasn't really there anymore. Figure the backpack was either catching the wind or else making her arms tired meaning unwanted inputs into the bars hence weaving, pretty obscure but the solution seems to be get a topcase!!! she was going to anyway.
Possible causes (Chopperman
1) Air pressure in the tires
2) Funky tires
3) Bent Rim
4) Too much weight on the back.
5) Soft shock setting in the back, harder setting in the front.
6) Swingarm alignment/Bearings problem
7) Rear wheel alignment problem or Front wheel alignment problem
8) White knuckles on the grips
9) Big furkin' back pack on the rider
10) Wheel bearings gone t-u or Front Wheel Bearing Replacement FAQ
11) Steering head bearings loose, tight or worn
If you have a lowered F650 Classic or GS, or just raised a Lowered GS, CHECK THE Amount of Oil in the Forks ! Also check the rest of the lowered Specs. Refer Lowering Kit FAQ & Lowering Kit FAQ GS ed.
My bike is great now, so into the garage with my girlfriend's f650. There is a weave which develops at motorway speeds, loaded up as well as with just rider. If you give the bars a tug in either direction the bike wobbles quite badly at anything over 30mph. Very different to my f650. I thought it could be the steering head bearings, some of the grease has melted out of them onto the round plastic guard. I've tightened them up quite tight but wobble is still there. The tyres are good and pressures are fine. I have just fitted a lowering, changing to a different shock, the weaving was there before and after, no change. Adjusting the shock makes no difference. No play in the wheel bearings either. Do you think the bearings could be shot and just need replacing or is there anywhere else I should look. Ed, UK
Sounds like the steering bearings may be notched (and need to be replaced). lift the front wheel off the ground and move the bars back and forth. If you feel a notch in the center of the movement, plan on replacing the bearings. Then is must be low tire pressure or worn tires. Could the steering bearings be too tight? That can also give a similar feeling. Richard #230, Pacifica, CA
Given that you
have already looked at some of the common problems you might want to start
checking that all the bike frame components are secure. I would investigate:
- swingarm pivot
- both axles
- both wheels for trueness
- broken frame (long shot)
- loose suspension components, BradG 1002, N, CA '01GS
Did YOU re-grease them? For that matter, has ANYONE re-greased them? They should be re-greased with the RIGHT grease and re-torqued properly. The wrong grease will leave, same as no grease. Which can cause a wobble. Over tightening or undertightening will cause a wobble, too. Consider that the FIRST place to look whenever something goes wrong is the LAST thing you did before it went bad. If it was steering head bearings, there's your culprit for sure. Flash #412 (CO)
Check routing of cables. Is the throttle cable pulling tight on a fork leg (wouldn't notice it when stopped) for example? Have you snagged/pulled out of position anything when putting a tank bag on? I've heard of others experiencing weaves with panniers fitted. So could just be an aerodynamic thing. Paul W (UK) Dakar - 30-Sep-02
Well problem solved. You will recall I said tyre pressure was not an issue. Leaking valve was an issue and with front tyre pressure dropping slowly I did not pick it up straight away. 15 psi on the bitumen tends to have a impact on tyre performance. Gnarly Adventurer.
"Light" Steering Feel
Symptoms: The steering on my 2002 650GS has gone a bit "light" recently.
It feels like the tyres are over-inflated but they're not. Any likely
Solution: I've just had a call from my dealer and the fork seals are gone after 4,500 miles hence the light steering. I said that I had read on the internet about suspect fork seals on the GS and he said, "don't believe everything you read on the net". Replacing under warranty. AndrewC (UK)
Check Tyre Wear or Pressure
Cranked up the preload and changed the steering geometry?
Check the Steering Head Bearing Grease?
Forks slipped down the Triple Tubes? Lowered Bike?
Fork Oil Old or Missing?
Ice on the road? Flash 412 (CO)
Steering bearings loose? I have had that "quick steering" feeling before on some of my bikes, also. Most of the time it turns out to be psychological, caused by slippery streets and cold weather (making the rubber tires feel hard) and the resulting slightly lessened drag in the bars, but sometimes it is just the result of your brain expecting the worse and sending warning signals that make you more sensitive about such things. You might try lowering the pressure in your tires by a couple of pounds and see if that helps. Worn tires can also cause unusual inputs into the bike's steering and handling. Richard #230
I have the same issue on my 98 Classic. Checked the pressure, tread wear, steering head adjustments, wheel bearings, all are fine but it feels a little vague. It is not icy here, just very wet, but then it is very wet all year round and the vagueness is a recent phenomenon. Next up is to check the fork oil, I have never replaced it, so its long overdue. Cannot see any sign of leakage but then the roads are so filthy I cannot see anything within ten minutes of leaving the house. Simon in Ireland
High Speed Wobble
I have been very annoyed by the high speed wobble problem since I got my 02 GSA with BMW bags. Increasing the rear tire pressure helped some, as did moving a couple of heavy small items from the saddlebags to the tank bag. Increasing the preload didn't seem to help. A couple of weeks ago, on the last day of an 11-day trip, we went 780 miles on I-80 across Nebraska and Iowa. In the morning, there was a strong side wind, the wobble was terrible, and I had to slow down because the wobble was so bad. By afternoon, the wind was from behind and the wobble was gone. I hadn't adjusted the load or the shock settings. I've had two different mc mechanics suggest that my bike needs a steering dampener when I described the problem. I have not seen any mention of steering dampeners on this board or the FAQ. Does anyone have any experience with them on this bike?
No. Steering Dampeners are not needed on the F.