I have a '94 M900 and was riding at a spirited pace on a highway this weekend. The weather was windy but I have experienced worse. I noticed that front end seemed twitchy - almost like the front on the bike was oscillating side to side. When I backed off the throttle, the bike seemed more settled and when I got on the throttle, I noticed the same behavior. What are potential causes for the twitchy feeling and can it be corrected with a more forward body position?
How old are your tires? Checked tire pressures? Maybe a wheel weight came off? umm, steering head bearing? ???
rear tire is is less than one year old; i'm not sure about the front one since it was already installed when I bought the bike. I checked the tire pressure that day and it was 36psi for both tires. Don't know about the steering head bearing. Today I was a able to duplicate the feeling by at low speed by swerving the bike. Maybe what I experienced this past weekend was just in my head, but I'll pay closer attention in the future.
have you changed anything in the geometry of the bike? moved the forks up or down, messed with trail (fork swap? clipons? ride height?)
the monsters are a little twitchy out front to begin with. highway speeds, combined with wind gusts, may make the front end float a bit.
happens to me sometimes too, usually wind is involved... but i've also decreased trail a little bit by doing a 999 fork swap, thus making my front end a little less stable than stock, but it has GREAT turn in.
i'd venture to say it's NOT your steering head bearings... but if it's a '94, i imagine the mileage is up there. you may want to look at replacing them whether they're the culprit or not.
Also, check this thread out as well:
http://www.ducatimonsterforum.org/index.php?topic=52708.0 (http://www.ducatimonsterforum.org/index.php?topic=52708.0)
Offhand, 36 psi for the front is pretty high I think... I normally run 32/36 front/rear. Maybe try bringing it down?
I run 31 on my front, 36 is pretty high for either tire. You'll wear out your tires much more quickly with them pumped up so high. Not sure how much that alone would affect twitchiness. If the front tire is old and it's pumped that high it may be bulging irregularly. If you lowered your triple clamp any that would make it twitchy.
it's a '94 and probably never had any suspension maint. done.
find a local suspension guy and have him flush and put in fresh shock & fork oil.
you'll be surprised at the difference.
assuming your 94 runs the same tire pressure as my 96, your front should be at 30 and your rear at 33.
I'll lower the pressure in the front tire since the general opinion is it's too high. The previous owner had FBF setup the suspension which included the installation of Racetech rear spring but I don't know if anything was done with the front. Regardless, it make a lot of sense to visit a suspension guru so that seems the way to go.
prolly just the wind. try it again on a calm day.
Quote from: gwjcat on April 17, 2012, 08:59:31 AM
I have a '94 M900 and was riding at a spirited pace on a highway this weekend. The weather was windy but I have experienced worse. I noticed that front end seemed twitchy - almost like the front on the bike was oscillating side to side. When I backed off the throttle, the bike seemed more settled and when I got on the throttle, I noticed the same behavior. What are potential causes for the twitchy feeling and can it be corrected with a more forward body position?
Often (most) times it's caused by your input.
The simple act of opening the throttle at speed can cause you to add input to the bars. Add wind and perhaps some wear or a tire pressure issue and it can get twitchy.