2001 DR650SE, 15,000 miles, TKC80's, superbrace, Eibach .50 front and .81 rear springs... Heres the deal, Bought the bike used with very flat deathwing front and IRC rear with a 16 tooth counter-sprocket; it would run past 90 straight and true. Over the winter I got the itch and swapped springs, new tires, superbrace, and added an IMS, 14 tooth CS, and happy trail luggage system if that matters. re lubed the steering head bearing and properly tightened it as perthe manual. It has no movement pulling on the forks with the bike up off the ground, and moves smoothly back and forth though there were small wear marks on the bearing race when I had it apart. Bike handled deals gap twisties beautifully, but when on the superslab and traffic is running 70mph plus, the front end starts to wobble back and forth, slowly at first, then faster unless I chop the throttle and slow down. Feels like its going to throw me off if I let it go. oddly enough, with a ton of gear loaded on the back and in the boxes, I can make it to 80mph before the shake starts???:huh I would post in the DR650 thread, but things can get buried quickly there... So, is it the TKC's? my bearing? the stiffer suspension? mind you I dont own a DR for speed, I would just like to be able to safely keep up when forced to ride with fast traffic!:eek1 Thanks all! DH
Try taking one hand of the bars- seriously. My old XT350 with knobbies was very unstable feeling at highway speeds to the point that I thought it would get way worse, then I lightened up my grip on the bars. My DR would do the same at times, mostly if I made any inputs to the bars at speed. My theory is that a tall front wheel combined with few contact patches from knobbier tires allows movement. You arm muscles are poor dampeners to oscilations that may set in, and in fact increases them. The tire will settle back into a straight and narrow running track (which it wants to do normally). It is true that changing the front rear weight bias will affect this as well. All this assumes that the SH bearings are fine, no warp in the wheel/ tire /spokes or any other maintenance deficiency
What pressure are you running in your tires? Too much or too little can cause the wobble. Try running stock pressures of 25 front and 29 rear and see if it gets better.
Wheels balanced correctly? Don't neglect the rear wheel, as problems back there can effect things up front...
Hmm, had a nice ride today with almost nothing in the boxes and the beast let me do about 80 again??? I think my issue must come and go? I always run the tires at 25/29 recomended pressure, unless I am heading straight for the trails. And I always have a loose grip on the highway to avoid tingly hands... Something else I remember, it will start to do the wobble when I stretch my legs out straight when on a long trip, and then dissapear when I bring them back to the pegs. I am very good about maintenance, though, I never had the tires balanced by a shop. I pried them on myself and did the old "fast spin" with the bike up on a stand, and both wheels didnt oscilate or anything, though I doubt Im spinning thm the equivelant of 70+ MPH obviously. It may be a small enough balance issue it only shows up then? Thank you all for the help, I will double check the things you have mentioned. DH
Hi, I know this is an old thread, did you ever figure out what was causing this head shake or what cured it ? Ive got a similar set up on my DR650 - .50 eibach fronts, 8.1 rear, HT panniers and at 120 + kmh/75 mph It gets a severe head shake... cheers Gip
I think your problem might have to do with the front being too low, back too high. Have you adjusted the preload or changed the spring on the rear? You mention the shake improving when the rear is loaded so that would tend to suport the theory. Prehaps the front dampening cant compesate for the stiffer springs and weirdness? Who knows? I had the same symtom on my DR 650 when I raised the front forks in the clamps to sharpen the stearing. It did sharpen stearing but also lead to the speed wobbles. I moved them back.
Loving my new-to-me dr650 and i was wondering if a steering damper would help. As i said i love the bike both on and off road and would love to do a few longer road trips so i dont mind dropping the 650 bucks on a damper...but i want to know its going to work.... The problem started for me when i switched to knobby tires. At speed the steering is extremely touchy. I know road tires would be the obvious choice for a road trip anyway, but even shorter trips i like to do out to the trails have a lot of highway in them.
Is your SAG set up correctly - get that sorted first. (This setting will change riding fully loaded and with no gear.) Where are your forks set in the triple clamps - the higher the clamps on the forks, the more stable at high speed. Lowering them will improve the turning ability. You probably want the clamps down the forks as far as you can without getting the wobbles up high. Steering Dampers might "suppress" the problem but you are definitely better to fix the problem rather than suppress it.
Changed back from knobbies to dualsport tyres, problem solved :) Less capable bike now but im no longer fearing for my life on the highway...well no more than usual.
Wonder if thats whats going on on mine . Im running T63 which are the most aggressive DOT knobs I've seen and Im getting the 70 75 + headshake too .
I had Mitas e07 on mine and noticed a little head shake. Got much worse when I switched to tkc80's. Like super scary twitchy over 65mph. I'm wondering if a fork brace would help?
