Rear Wheel Lift

I did not hack my KLR650 just because of a couple of missmatches between KLR and Velorex. When I saw a Sputnik on an ISCH I was recalling my experiences with the MZ/Superelastik during my university time. After once the nose got stuck on a paving stone I mounted PE / UHMW-PE plastic in the touch down corner. So it would slip - not catch.
Anyhow the collegue never again rode with me home....Why? I cannot tell - (yo no fui- Ich? Aber nicht doch)

The KLR suspension is extremely soft and as well the Sputnik (and the Superelastic) You should think about a torsion link between both suspensions for to get rid of this wavy behaviour.
This will join both swings and avoid that one goes up and one down, but both will lower in bends and this way the rig stay more stable in bends.
In the MZ there were on both swing arms a capturing cup with rubber in which the torsion bar would fit in. The torsion bar was shaped as a hat, made out of 5/8" - 3/4" spring steel and mounted with 2 rubber patched clamps to the front beam of the sidecar.
As long You do not feel confortable with the rig, continue to improove its design.
Best if You contact a knowlegable specialist if You are just starting with this new hobby.
Sven

Thanks! I was looking into the torsion link. Is that something I can make at home or require special attention when creating one...

Here is a sample of one of Claude Stanley's anti-sway bars:

Edited for pic of KLR/Sputnik rig (a pic I think you've seen at: http://www.advrider.com/forums/showthread.php?t=891295) .

Also see this recent discussion where, as c64club points out below, stiffening the suspension improved handling: http://www.sidecar.com/mbbs22/forums/thread-view.asp?tid=11186&posts=23&start=1

Another pic, just because I like the nose-to-tail racing stripes:

The simpliest and fastest way, before you design and make some changes, is to pack every heavier things as close to rear wheel as possible. And as far left-rear as possible from the line that connects the points, where bike's front wheel and car's wheel touch the ground. And also try to make bike's suspension somewhat harder. KLR's suspension is softer than sputnik's one. Try to fill bike's damper with heavier oil.
Then you have time to tune your hack 🙂

The rear wheel lift might be because you are cornering to the left at an unsafe speed.

Thanks for your input everyone! I have slow my speed down a bit and also have gotten use to shifting my weight around on the sidecar during the turns. There is a bit of learn curve but I can't get enough of it. I did order a new shock in hopes to replace the sputnik one. Also I'm getting with a fabricator to help build a sway bar/torsion spring for my hack. That should help out a bit as well.