Page 2 of 4 FirstFirst 1234 LastLast
Results 11 to 20 of 37

Thread: Fu@#ing death wobble

  1. #11
    Senior Member Cooter's Avatar
    Join Date
    Dec 2012
    Location
    Crawling up your skirt
    Posts
    6,814
    1.5mm of (effectively sag) made any difference!?! Ummm.... It would be like having the bike steer differently whether you ate dinner or not. Glad that worked for you, I wonder what the cause was?

  2. #12
    Senior Member mmcn49's Avatar
    Join Date
    Jan 2010
    Location
    Small Island in Puget Sound, WA
    Posts
    251
    In 72 I bought a new R75/5 Beemer. That bike and the model in general had wobble issues. Problem was caused by one or the other fork binding. One or the other would bind up while the other slid. A couple redesigned parts solved the issue.

  3. #13
    Senior Member Silverrider's Avatar
    Join Date
    Sep 2016
    Posts
    2,552
    I had a wobble once here was the issue.
    neck bear.jpg

  4. #14
    Senior Member
    Join Date
    Apr 2018
    Posts
    145
    Quote Originally Posted by njloco View Post
    So cossack, are you saying that someone lowered the front forks for some reason or it came from the factory like that ^^^^^^^^^^ ?
    I bought the bike that way, they were ran up into the triple tree all the way in against the clips.

  5. #15
    Senior Member
    Join Date
    Apr 2018
    Posts
    145
    Quote Originally Posted by Cooter View Post
    1.5mm of (effectively sag) made any difference!?! Ummm.... It would be like having the bike steer differently whether you ate dinner or not. Glad that worked for you, I wonder what the cause was?
    I'm not familiar enough with motorcycle geometry to be able to explain it, but it is not as simple as you put it. Adjusting high of the front end has effect on entire set up. After repairing/replacing all the usual suspects, then, setting rear sag, front sag, adjusting compression and rebound and finally raising the front of the bike up, it is rock solid at any speed. Where is before it was ok up to 90mph, after that, she was very wobbly and shaky.
    Last edited by cossack84; 04-30-2019 at 01:15 AM.

  6. #16
    Junior Member
    Join Date
    Sep 2019
    Posts
    6
    Quote Originally Posted by cossack84 View Post
    Mine did that too, after replacing all the same parts I raised front forks by 1 mm. Bike ran a lot better, then I raised it 0.5mm more and it completely stopped.
    Sorry to sound dumb, you made it so there was more or less fork sticking out the top yolk?

    Thanks

  7. #17
    Senior Member
    Join Date
    Apr 2018
    Posts
    145
    Quote Originally Posted by Owenator View Post
    Sorry to sound dumb, you made it so there was more or less fork sticking out the top yolk?

    Thanks
    More, I moved forks in 1mm increments.

    Edit.
    I was wrong, less fork sticking out the top.
    Last edited by cossack84; 10-06-2019 at 03:51 AM.

  8. #18
    Senior Member
    Join Date
    Mar 2015
    Location
    Phoenix, AZ
    Posts
    1,218
    Quote Originally Posted by cossack84 View Post
    More, I moved forks in 1mm increments.
    "Usually" raising the bike (lowering the tubes) tends to lead to high speed unstability. Usually...

    Can you now see the stopper rings (#19) on the tubes? Maybe a PO pulled the rings off the tubes and lowered the front too much? Usually with those in place, the front end can only go down so far... but with the clamps loosened you can slip over them with enough pressure.


  9. #19
    Senior Member Cooter's Avatar
    Join Date
    Dec 2012
    Location
    Crawling up your skirt
    Posts
    6,814
    One MM of compression = about 6.2lbs* of weight with stock spring rate at stock sag. So pretty much nothing. The change in rake/trail is four digits past the decimal point. I call BS.

    I appreciate a discussion on steering geometry and the theory is correct, but it's only theory in such an infinitesimal quantity. If you start talking in single digit denominator fractions of an inch (because Murica') then... maybe.

    Theres NO way a mortal human could tell the difference by raising the forks ONE MM, or that it would affect the handling of a motorcycle in any way.


    *rough but close calculation, but really... one mm!? sheesh. Crank up the heater! Its 72* now and I'm more comfortable at 72.0001* hahahaha.

  10. #20
    Senior Member Cooter's Avatar
    Join Date
    Dec 2012
    Location
    Crawling up your skirt
    Posts
    6,814
    Quote Originally Posted by 34nineteen View Post
    "Usually" raising the bike (lowering the tubes) tends to lead to high speed unstability. Usually...
    Yup. Exactly. Because it's increasing the rake* and Buells are already pretty maxed out!



Page 2 of 4 FirstFirst 1234 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •