Originally Posted by
cbr2702
If you add an idler I don't think you need to modify the frame from the traditional diamond that supports the wheel on both sides.
Yes, this exactly.
Maybe with more than one joint, if it needs to be more compact? (Again, I'm no mechanical engineer.)
Interestingly, the one in the auction lot above had it on both sides--that would seem to have something to do reducing with play from slackening/extension of the linkage by opposing the action on either side?
There must be something undesirable about this arrangement, yes?