Finished new install of new leading link assembly on my BMWK100RS. This is a quality unit manufactured by Wasp cycles in the UK. Attempt to take my first ride resulted in an absolutely uncontrollable shimmy from start to stop. I have a shimmy dampener installed, again a quality unit specifically for sidecar use, previously installed on my bike with a stock front end. I am unsure as to where to begin, perhaps someone can suggest a direction to move in. I have informed the manufacturer but have not received a response as of yet. Suggestions would be appreciated. Thank you, Craig

Hello Craig,
Maybe look at the shocks you have on the leading link and their settings. Too hard will make things skip around a bit and feel like it wants to tank slap. That might be a starting point for you.
Sean

Maybe post a picture of your forks.
I have Wasp forks on my K1100 and they are quite stable although I do have a steering damper (VW type).
Other thoughts: Are your steering head bearings ok? Also, the Wasp forks move the wheel forward a bit. You need to check the toe in and lean out are ok.

Thank you for the replies, The steering head bearings are ok,I checked them this week, they were replaced and adjusted when I rebuilt the bike 5000 miles ago. I think the problem is associated with the front axle and the spacing between lower yoke ends and the wheel. The wheel will run free until the pinch bolts and the axle end bolts are tightened and then there is a lot of drag on the wheel.  I do not know if your setup, in regards, to the wheel spacing is the same as mine, 1985 K100RS but I had to install 8, 3 mm washers on the right side, looking at the bike from the front, just to get the brake strut in the proper location. I cannot ride the rig the way it is as the front end wobbles and shakes as soon as I start moving and gets worse as the speed builds to the point where it is completely uncontrollable. I have heard from Wasp once and he is surprised,  I will give him another week to respond , I have sent him photos of the install and dimensions. If I do not hear from him by next week I will remove the assembly and restore the OEM front end and consign the unit to the bin, chalking it up as an expensive two year wait for something that does not work. Thanks again for your input, it is much appreciated. At 74 my riding time is finite, no time to waste on diagnosing a problem that should not be, I would rather be riding. Thanks again Craig

Pictures of your sidecar and of your leading link would help.
The shimmy is usually due to a bad trail value. Is it adjustable?
If not, try with adjusting the front shocks preload (reduce it so it lowers the nose). You can play also with the tubes's height in the triple tree. Try to know if changing your position on the bike has an effect on the shimmy(or use a passenger)
Did you ride this side car before with conventional forks?
Did you change settings of the sidecar frame? A leading link reduces the trail, so it extends the wheelbase automatically. That may make necessary to adjust the sidecar wheel precession (1/6 of the wheelbase as a basis).

Last hypothesis : get used to. I've seen sidecar drivers unable to avoid shimmy only because they were overcontracted on the bar. No problem at all with other drivers. Consider this if you're used to ride with conventional forks, that require firm handling, not needed with leading link.