High speed wobble

Discussion in 'General VMax Questions' started by torszula, May 29, 2013.

Help Support VMAX Motorcycle Forum by donating:

Tags:
  1. Apr 9, 2016 #141

    blaxmax

    blaxmax

    blaxmax

    Well-Known Member

    Joined:
    Sep 6, 2014
    Messages:
    2,864
    Likes Received:
    0
    Location:
    palm springs ca
    I'm not so sure that's to do with the cold air.
     
  2. Apr 9, 2016 #142

    Specs95t

    Specs95t

    Specs95t

    Well-Known Member

    Joined:
    Aug 2, 2015
    Messages:
    341
    Likes Received:
    0
    Location:
    Albany NY


    Have you had/heard of similar?
     
  3. Apr 9, 2016 #143

    blaxmax

    blaxmax

    blaxmax

    Well-Known Member

    Joined:
    Sep 6, 2014
    Messages:
    2,864
    Likes Received:
    0
    Location:
    palm springs ca
    I haven't but cold air will lose a few pounds of pressure. I don't think enough to do what yours is doing.
    I would check the steering head bearings.
    I can let completely off the bars with a cruise control and it stays in a straight line.
     
  4. Apr 9, 2016 #144

    tothemax93

    tothemax93

    tothemax93

    Well-Known Member

    Joined:
    Oct 20, 2009
    Messages:
    2,133
    Likes Received:
    1
    Location:
    Elma NY
    It would be interesting to see if you got a wobble without the cruise on, decelerating. That's when I would get a low speed wobble.
     
  5. Apr 9, 2016 #145

    blaxmax

    blaxmax

    blaxmax

    Well-Known Member

    Joined:
    Sep 6, 2014
    Messages:
    2,864
    Likes Received:
    0
    Location:
    palm springs ca
    I don't. I have no wobbles at all.
     
  6. Apr 9, 2016 #146

    DMAN999

    DMAN999

    DMAN999

    Well-Known Member

    Joined:
    Apr 15, 2010
    Messages:
    3,300
    Likes Received:
    0
    Location:
    Hamburg, NY
    I use a throttle lock (on the highway at 7-80 mph) on long rides and have never had any wobble when doing that.
    But I also do the bounce test every Spring and adjust my steering head bearings as needed.
    The only time I ever had any wobble it was a low speed wobble (40-45 mph when decelerating) and it was caused by a worn/cupped front tire.
    I replaced the tire and it disappeared.
     
  7. Apr 10, 2016 #147

    Lotsokids

    Lotsokids

    Lotsokids

    Well-Known Member

    Joined:
    Jul 17, 2009
    Messages:
    558
    Likes Received:
    0
    Location:
    Oklahoma City, OK
    When I let go of my bars (without cruise control), my bike leans / turns left... slightly. Every time.
    That's why I think I have a front / rear wheel tracking issue.

    I can verify that comment also! I had that same issue on a different bike (FJ1200). Replaced front tire, problem solved. Seems sort of common.
     
  8. Jul 12, 2016 #148

    Lotsokids

    Lotsokids

    Lotsokids

    Well-Known Member

    Joined:
    Jul 17, 2009
    Messages:
    558
    Likes Received:
    0
    Location:
    Oklahoma City, OK
    WOBBLE CAUGHT ON VIDEO

    Last couple days were bad "wobble" days. I finally decided to record it with my GoPro.

    Here is is. I'm going into town. Yes, I'm wearing shorts - a risk I take on super hot days, but not on longer rides.

    Speed when wobble started: About 200 Km/H (124 MPH). Hard acceleration, bumpy road = wobble generator. It felt more violent than the video captured. Watch my right knee in the video.


    Here's the video: http://vid5.photobucket.com/albums/y177/Lotsokids/V-Max/New%20VMax/V_Max_wobble_zpsyysjuh9c.mp4

    Recap of my maintenance to date:

    - Replaced rear tire.
    - Replaced original fork springs with Progressive springs. New oil, and zero air pressure.
    - Replaced fork brace with HUGE thick steel brace.
    - Front tire air pressure is leaking very slowly. Wobble exists at 20 PSI and 40 PSI. Air pressure is not the root problem.
    - Replaced upper and lower steering head bearings and races. Tightened with "Bounce" method, then a little tighter.
    - Re-torqued swingarm bearings.
    - Manual "shakedown" of front and rear wheels. No obvious free play in axle bearings.

    I've owned (2) 1985 V-Maxes prior to this one, but no wobble at all on those. And those had the smaller fork tubes than my current 1999 model.
     
  9. Jul 12, 2016 #149

    Miles Long

    Miles Long

    Miles Long

    Well-Known Member

    Joined:
    Oct 14, 2009
    Messages:
    1,939
    Likes Received:
    0
    Location:
    Saint John New Brunswick
    You should put a photo of your daughter behind your flyscreen.
    High-speed wobble issues will never again be an issue.
    Cheers!
     
  10. Jul 12, 2016 #150

    sdt354

    sdt354

    sdt354

    Well-Known Member

    Joined:
    Aug 8, 2008
    Messages:
    5,567
    Likes Received:
    5
    Location:
    Southern N.E.
    That looks constant. Run-out, somewhere up front?
    Just a reminder to all. When tightening head bearings,the fork get compressed. It's a good idea to loosen the clamps on the trees, shake the forks into alignment, then re-torque the tree clamp bolts. Later style forks-make sure if you slid them up the trees to lower the front, it's equal on each tube.
     
  11. Jul 12, 2016 #151

    jfeagins

    jfeagins

    jfeagins

    Well-Known Member

    Joined:
    Aug 18, 2006
    Messages:
    3,960
    Likes Received:
    0
    Location:
    ..
    Put 'er up on the center stand & video it running so's we can see the back tire/wheel whilst it's spinnin'. 2nd-3rd gear slightly above idle should do it.
     
  12. Jul 12, 2016 #152

    Fire-medic

    Fire-medic

    Fire-medic

    Well-Known Member

    Joined:
    Mar 25, 2011
    Messages:
    8,642
    Likes Received:
    11
    Location:
    Miami Florida
    Hah, a good one, Miles! A reminder about what is precious.

    That road looked to be nasty-bumpy! if you did it on a perfectly-graded road, then maybe I wouldn't chalk it up-to the road condition.

    I wouldn't use any tighter than spec front end torque for the steering head. If you have it set to Sean's recommendation, that's it, don't go for the tighter setting. Also, try running 10 psi in the front fork, assuming you still have the capacity. For me, running no air vs. being pressurized is a big difference in steering accuracy, compression under under braking, and jounce absorption (the opposite of rebound).

     
  13. Jul 12, 2016 #153

    Miles Long

    Miles Long

    Miles Long

    Well-Known Member

    Joined:
    Oct 14, 2009
    Messages:
    1,939
    Likes Received:
    0
    Location:
    Saint John New Brunswick
     
  14. Jul 12, 2016 #154

    Lotsokids

    Lotsokids

    Lotsokids

    Well-Known Member

    Joined:
    Jul 17, 2009
    Messages:
    558
    Likes Received:
    0
    Location:
    Oklahoma City, OK
    Yes, I believe there is something to that. Like I've said before, I think I have a front to rear wheel tracking problem. Because of the way it acts, (leans left when I release the bars), I think the front wheel wants to move a little right compared to the rear. So obviously on rough roads and/or hard acceleration, the front gets light and wants to drift to the right creating a wobble.
    Just thinking out loud. I'm not a specialist.

    By the way - No wobble on the drag track. Maybe a couple times, but very, very minor and completely controllable.
     
  15. Jul 12, 2016 #155

    Tex85

    Tex85

    Tex85

    Well-Known Member

    Joined:
    Dec 26, 2012
    Messages:
    1,885
    Likes Received:
    1
    Location:
    Columbia, SC
     
  16. Jul 12, 2016 #156

    Miles Long

    Miles Long

    Miles Long

    Well-Known Member

    Joined:
    Oct 14, 2009
    Messages:
    1,939
    Likes Received:
    0
    Location:
    Saint John New Brunswick
     
  17. Jul 12, 2016 #157

    jfeagins

    jfeagins

    jfeagins

    Well-Known Member

    Joined:
    Aug 18, 2006
    Messages:
    3,960
    Likes Received:
    0
    Location:
    ..
     
  18. Jul 13, 2016 #158

    Miles Long

    Miles Long

    Miles Long

    Well-Known Member

    Joined:
    Oct 14, 2009
    Messages:
    1,939
    Likes Received:
    0
    Location:
    Saint John New Brunswick
     
  19. Aug 29, 2016 #159

    Lotsokids

    Lotsokids

    Lotsokids

    Well-Known Member

    Joined:
    Jul 17, 2009
    Messages:
    558
    Likes Received:
    0
    Location:
    Oklahoma City, OK
    MOST VIOLENT WOBBLE TO DATE

    I rode conservatively for 4 hours yesterday. No wobble at all.

    But I rode to work today and the wobble showed itself... many times. EVERY TIME in two corners, hitting a couple known dips in the road, at steady speed - about 65 MPH. So not necessarily only during acceleration. There is one area (location of my previous wobble video) that is notorious for generating a wobble. It's a bumpy road with some issues in the road surface. But it's long, straight, and open - hard to not hit the throttle.

    So today I hit it, and when I reached about 70 or 80 MPH the beast immediately started a VIOLENT wobble. I don't know the proper way to respond other than "white-knuckling" the handlebars and riding it out. But today was different. It was bucking so hard, it bounced vertically OFF THE ROAD. It was very literally like riding a bucking bronco. It was all I could do to keep it vertical, but I did. I could feel both tires leave the pavement a couple times. I was all over the place, but didn't crash. That was just crazy.

    The strange thing is that it's not consistent. Some days are better than others. Today was CERTAINLY a bad day!

    I'm left with nothing else to check, and nothing else to change other than major components like swingarm, frame, or forks.

    One thing is consitent - No wobble on a flat, smooth surface... like the drag track.
     
  20. Aug 29, 2016 #160

    Tex85

    Tex85

    Tex85

    Well-Known Member

    Joined:
    Dec 26, 2012
    Messages:
    1,885
    Likes Received:
    1
    Location:
    Columbia, SC
    Looks like you had a good exercise in sphincter control today! Glad to hear you were able to keep it vertical, I imagine it was quite the adrenaline rush.
     

Share This Page

arrow_white