Need front end input

Discussion in 'Dyna Models' started by R_W_B, Sep 21, 2011.

  1. R_W_B

    R_W_B Senior Member

    Must be loosing my mind since I thought I had already posted this but couldn't find it. So here it is now.

    Haven't been able to ride the bike much since I put it back together, due to having some work come in and also my front brake was a pain to bleed properly. However I did take it down the road today at lunch. After doing my vertical alignment it does seem to ride a little straighter when I take my hands off the bars.

    However here is my current confusion. My bike has ALWAYS had a front end wobble IF I let go of the bars. However while holding onto the bars I have ridden many hundreds of miles at different speeds up to 85 mph and never once had any kind of wobble or weave on curves, straight whatever, riding single or 2up.

    But if I let go of the bars, a wobble begins. Now before I set my Vertical Alignment I could not let go of the bars very long so the wobble never had a chance to get going. But today going about 40mph with the throttle friction holding, I let go of the bars and after about 2 seconds or so the wobble started, and steadily started to get worse so that I grabbed the bars for fear of it getting too violent.

    All of the below was done BEFORE I took it for a ride.
    I moved the engine brace bout 3/16 inch left while doing my vertical alignment, so to be on the safe side I loosened both rear and front motor mount bolts and (while sitting on the lift) cranked the engine for bout 5 or 6 seconds and rev'd it a few times to let the tension equalize before I torqued the mount bolts back down. The Vertical alignment is literally dead on (Back disc matches front disc).

    The bikes rear alignment is dead on (has been for some time). The bike's front motor mount is only about 8 months old (put it on myself and shimmed the preload out of it).

    The tire pressue is good.

    I have checked my fall away twice since I had the bike, the last time being only a couple of weeks ago. It's total fall away distance is right on 4 inches.

    So I'm thinking (even though 4 inches is within fall away specs) I need to try tightening the star nut some more. And if that doesn't work I need to replace my steering head bearings. The bike only has close to 16,000 miles.

    I did a google search and found several hits on a forum that I don't even belong to, they said these items in no certain order. What was so interesting about each one is they all said after they corrected the item, then the problem went away.

    Tire or wheel
    Front end loose or bad bearing
    Tube distance above top tree different on each tube
    Tree pinch bolts loose.
    Fork tube oil old with air, or not heavy enough.
    Oh and not to forget the answer the HD tech gave ' don't ride with no hands '
  2. Hoople

    Hoople Account Removed

    At just 40 MPH in a straight line, that should never happen.

    1) When you say the rear wheel is in alignment, what method did you use.
    2) What is the runout in BOTH planes of your laced wheels and are the spokes tight.
    3) How did you perform the weight balancing of each wheel.
    4) You have sealed 6205 wheel bearings, both front and rear. Is there ANY side play.
    5) When you jack the bike up and turn the tires, is there any irregularities in the tires that can be FELT or seen. At 16K miles, your on your 2nd set of tires correct? This happened with the original tires also. You said your bike has always had this problem. Even when it had 2K miles on it?
  3. R_W_B

    R_W_B Senior Member

    1. Easy cheap rear alignment tool. - Harley Davidson Community

    2. I haven't checked each individual spokes (yet) but most of them are tight when checked. Have not done a runout check, do I have to pull the wheels to do this ?

    3. The balancing was done by the dealer, has spoke weights at rim.

    4. No side play or clearance when pull in any direction of front or reat tire, no clunk when I pull forward on the front end either (all of these with bike on lift).

    5. I see no irregularities in either tire. When I turn the wheels (on a lift) the angle meter reports a 0.2 degree difference sometimes on a quarter turn. I have also found by checking a stationary item that the angle meter has a error factor of 0.1 degree from one time to another. So we can say that my brake discs show an average deviation in 1/4 rotation, of 0.1 degree, which in the radius of my wheel geometry calculates to about hair more than 1/64 inch of horizontal travel.

    Tire history is this, front tire came on bike a little over a year ago when I bought the bike used. Talked with previous owner and he said he put new tires on both front and back at 2000 miles before he traded the bike in to dealer. Front tire still has good tread and have gotten opinions from local riders that the very slight weathering cracks are not bad enough to replace yet. The rear tire was replaced earlier this year when I had a flat. Done by Clermont Harley dealership.
  4. Hoople

    Hoople Account Removed

    You are basing way too many measurements on assumption only.

    1) Disk brake rotor runout is meaningless. I meant the metal RIM (not tire) run-out in BOTH planes.
    2) The dealer did the balance. That is not good enough. You must do it yourself and first perform a balance of the rim only. Then match the tire dots and perform a final balance. Use the same tool (Marc Parnes) to check runout of the rims.
    3) Most of the spokes are tight when checked? That to me could mean a good portion are not.
    4) Is your rear axle 1" hollow or is it solid. Does your rear swing arm have a 1/8" hole about 4" forward of the axle position on EACH side.

    Something has to be WAY out to have a wobble at 40 mph going in a straight line. That is simply crazy. Don't preload the neck bearings any more than you should. That will only mask and not correct the root problem.
  5. R_W_B

    R_W_B Senior Member

    Oh yea I knew what you meant, do you have to remove the wheel to do it, or can I just put the bike on lift and put a whatever you call it on it (they sell them at H.F.).

    Oh well, that's gonna have to be awhile before I take tire off the rim. I've got too much going on right now. Hardly have time to even ride up the road some. But the DOT dots are in the correct position. And the wheels do not bounce or vibrate, but ride smooth all the way thru to 85 mph (with hands on the bars).

    I will check all the spokes, but so far I've had to do it with an adjustable wrench, where did you buy a wrench small enough for them?

    Jeez I have no idea, never had it off. It does have a dimpled hole in the end but I can't see thru to the other side. It's a OEM 2007 SB.

    It has the hole bout 4 inches forward. I use it to set rear alignment.

    Well I don't like it either, but you'd be amazed how many folks have reported back to me the same thing happening to them. It was one of the things I listed earlier or even some had this only when they had their windshield and bags on. Mine are still off, have not put them back on the bike yet.

    But like I say it's always did this since I've had the bike. But before I set the vertical alignment (recently) it pulled to the left so that I could not ride with no hands for longer than a second or two. Now after setting the V.A. it tracks straight enough for me to actually ride without the hands. The wobble starts about a second after I let go of the bars and steadily increases to an ominous level at around 4 to 5 seconds.
  6. Hoople

    Hoople Account Removed

    If your axle was hollow (like mine is) you could see right through it from end to end. I asked because it makes performing a proper alignment a challenge. It can be done,,,just a challenge.
    If you have centering points in each end of your axle, you have it made.

    You say the tire DOTs are in the correct position? Did you assume the valve stem position was the heaviest position? On my rear wheel, the valve stem position was not the heaviest position of the rim. It was on the front but not on the rear. See what I mean about assumptions.

    If we always assumed that new parts were good because they are "new" and that adjustments are right because "the factory did it that way", we would have no need for warranties.
    I don't assume ANYTHING. That's why I have no friends!:)
  7. R_W_B

    R_W_B Senior Member

    :lolrolling oh that's good, I haven't got a laugh like that since I read one of Mat's posts. Ugh .. well I understand you jest, since you certainly know that you have many friends, of which I hope be honored as included. One of these days I want sit somewhere drinking beer with you while all of your facts and figures transmit into my brain. :lolrolling

    But seriously I greatly appreciate your input and am certainly taking all of it to heart. I'm just not in a position right now to run out in the garage and start pulling my wheels off. Keep in mind this is the same bike I've been riding hundreds of smooth unproblematic miles 'with hands on the bars'.

    As far as the DOT and valve stem position rest assured I have read Marc Parnes webpage and almost bought his excellent static balancer before Brian showed me his. If I hadn't spent all my money on other things I would still buy Marc's. I am aware that the valve stem is not alwasy the heavy point of the wheel.

    But I did not mount the wheel so I cannot know those parameters for a time yet. However there are folks that swear by the machine balancer that the dealer uses even though I've read that only static balancers are seen in race pits.

    In any case I will try to eliminate things as I can. I desperately want a new set of HD cast wheels that I've already picked out, but just can't swing it right now. I am so sick of cleaning and dealing with spokes. I hate um.
  8. Breeze3at

    Breeze3at Well-Known Member

    I just saw the pic you posted about the front signal relocation brackets. I noticed that you have only 1 mirror on the new bars. Do you think there is any possibility that uneven wind resistance on that mirror could be contributing to your shimmy? Pushing the bar back, then the gyro effect brings it back? Far fetched, but I wonder.
  9. R_W_B

    R_W_B Senior Member

    Well it might be, I hope so. But I doubt it since my bike has always done it from day one (with both mirrors). I've got some issues going on right now so I just put the bike in the garage. Haven't had it out for days. When I get time I'm gonna check every one of the items you guys have given me though.

    Other than the no hands wobble the bike runs fantastic though. The Doebeck runs great just with the suggested settings, haven't had to fool with it at all. Idles great, runs strong thru all the rpms. My new TBars handle SOoooooo much better than the OEM mini apes. Course I have always loved Tbars from many years ago so that was no surprise to me.

    Thanks for the alternate viewpoint Breeze.

    Tuesday's Gone and Free Bird's gotta Gimme 3 Steps towards a Simple Man. Cause they don't call ME The Breeze but more like Every Mother's Son and love to spend my days listening to the Ballad of Curtis Lowe. Boy ain't it great when you are the thread starter LOL.

    Lynyrd Skynyrd - Simple Man - YouTube
  10. blueglide

    blueglide Member

    Hi, did a 3day road trip after I read your post, took my hands off the bars at various speeds on differing road surfaces-no wobble.
    Bike is 2011 Sbob 5k miles so should be still blueprinted as far as chassis goes.
    I could steer the bike with knee pressure and pressure on footpegs (mid pegs on mine).
    Wasn't expecting bike to wobble to be honest but just thought I'd experiment.
    Sometimes on twin rear shock motorcycles a bad rear shock can lead you into thinking that you have a front end problem.
    Have you had someone else ride your bike? some problems due to worn components are very incremental and the rider compensates as the miles go on.Sometimes another rider can pin a problem.
    Guess thats not much help, but good luck in finding the problem.