It definitely doesn't "pop" so that was the wrong choice of words. It disengages for an instant and the re-engages. I didn't use the term "slip" because slip to me would be gradual like a slipping clutch. The engine does rev in the interim. Yes, I know nothing good is going to come from having a revving engine and a sudden re-engagement of the gears, that's why I'm trying to run this down.

I will have to run it with the cover open to see what the gear selector is doing when it does this.

Thanks, and yes, I will post pics. I only wish I had taken some "before" pictures.

And any idea where I can find motor mounts? They look pretty shot too...