You overpaid your helpers vastly. The going rate, even for gringos on brand new Bavarian bikes, is US$5 or less per border--a couple of bucks is normally sufficient. For $20 or $25 they should carry you across on a gilded litter, change your oil, set valve clearances and have you home for a five course meal.
Plus: I've had a couple of occasions where I wasn't going anywhere without a genuine title--and yes, I carry a convincing color copy as well. Photocopies don't include any of the security features which all titles incorporate, and aduana personnel aren't stupid--merely lazy.
Besides, what's the risk? You carry a passport, right? Carry your title wherever you carry the passport.