Hello All,

I'm slowly moving through cleaning, servicing, lubing, etc. on my '77 Motobecane Grand Jubile. It came to me in almost perfect shape and I don't want to screw anything up. I'm a novice and I'm buying tools as I need them, and watching videos. So far, I've done the front and rear axles and the freewheel (clean, replace bearings, re-lube). Now I'm on the bottom bracket. I've pulled the cranks (with the correct classic SR Sakai puller that I bought used from a bike repair guy who was closing his shop), and ordered a couple of Park Tools, the HCW-4 and HCW-5, in order to remove the fixed and adjustable cups, so no problems so far.

Here's my conundrum: I've seen a couple of videos of this operation and in one the mechanic says that that the square tapered spindle and the female crank opening should be cleaned of all lubricant when re-fitted or the crank may be drawn up too far on the spindle and crack at the corners. I have a problem with this theory. I've lived on boats for many years and I know that dis-similar metals tend to destroy one another in the absence of any lubricant/sealant, so I instinctively want to lightly grease the spindle contact surface. Also, I would think that there is a standard torque setting for the bolts that would correct this issue (although I haven't seen it yet).

Here's my question for the experts: Should I leave an aluminum/steel interface clean of all protection in the interest of friction or not?

Here's my second question: Does anyone know the torque setting for drawing up the crank arms to the spindle?

I know these might seem like small matters in today's world, but I'm taking the Hippocratic approach to this beautiful machine – First, do no harm.

Thanks,
Brian