Tire stability rear

Posted by FastCletus on Jun 24, 2013; 5:06am
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/Tire-stability-rear-tp4042741.html

I am running a 120/90/18 on my 1980 cb750f. After a 150 mile road with my girlfriend on the back (I am 200lbs and she is 140lbs)  the rear end felt real unstable   I think the tire is too skinny.  Been reading some threads but haven't seen one that answers my question.

Being that her and I plan to ride alot (with saddle bags in the future) what size tire should I use or is what I have on as good as its gonna get.    I would assume a bigger tire would make it more stable. If so how big?

Front tire size is 100/90/19