Bicoupler wobble?

[technion]

Hey guys,

I wouldn't have thought this could be simpler. One orange tank, one bicoupler underneath, and two nuclear engines.

I'm not sure if it's the engines of the coupler, but trying to accelerate in a kerbin orbit and these things wobble to heck. I was planning on using this as a tug but there's no way I would put any weight on it in its current state. Any idea what would cause this?

[Roastduck]

Have you tried bracing it with struts?

[technion]

Haven't tried struts. Whilst it's the obvious answer, I just didn't think two of the lowest thrust engines in the game would actually need them- the implication would be that the bi-coupler would be just about unusable as a part without struts if they were needed in this simple case.

[Vanamonde]

That's odd. I regularly use LV-Ns on bi-couplers and have never needed to strut them like the stronger engines. Pics of the ship might help.