ArtProf

Hi,

I have a 70's Montgomery Ward 5 speed (old ten speed) road bike. I'm unsure if it is an "Open Road" as there are no labels on it but it looks similar.

I'm learning by fixing it up and it came time to overhaul the BB. It's only got one cottered arm and appears to be a two-piece crank. I haven't found much information/pictures on vintage two piece cranks so confirmation on this would help. It seems a little rare but thought that if anyone else encounters it, they could find it here. The weird thing is that the outer cover for the BB NDS doesn't have the lock ring/slots like others do but the cone is the lock ring so to speak- turning it to release it all. Is this common for the time period or two piece cranks?

Everything seems to be fine albeit the grease has solidified - I'll probably dissolve it in some simple green or odorless mineral spirits (if really stubborn). However, the bearing cup on the NDS appears to be worn down on one side. I did replace the kickstand because the crankarm was rubbing against it - I thought it was the old kickstand which did have movement but maybe the arm was slowly moving towards the kickstand/getting bent? It appears straight.

I was going to just replace the bearing cup and grease it all up/repack but wanted to make sure that's what it might be before I'd have to just replace the entire BB. I'll need to read up more in order to replace it to figure out sizes and etc. Recommendations appreciated!

I've included photos so you can see the items and hopefully you can spot the worn down side/area of the bearing cup. You can notice it on the lip.

Two-piece Crank Bearing Cup Slideshow by ArtProf | Photobucket

Pompiere

I encountered a two piece crank on an AMF 3 speed and transferred it onto a folding bike because it had really short crank arms. Mine looks just like yours except for having a single chain wheel. The edge of the left side cup doesn't look like it has any effect on the bearings, so I would just reassemble it as is. The bottom bracket is pressed in, so you would need to find a threadless replacement in the correct size.

cny-bikeman

If there is a notch in the right side cup you would have to use a hammer and punch to remove the cone. If there is none then removal is not practical. The wear on the cups or cones just makes them run smoother, but any pitting is a reason for replacement. If the cones are not pitted get new cups and caged bearings and reassemble. If the right cone is shot and not removable I don't think it's worth putting money into a new crankset.

ArtProf

Quote:

Originally Posted by Pompiere

I encountered a two piece crank on an AMF 3 speed and transferred it onto a folding bike because it had really short crank arms. Mine looks just like yours except for having a single chain wheel. The edge of the left side cup doesn't look like it has any effect on the bearings, so I would just reassemble it as is. The bottom bracket is pressed in, so you would need to find a threadless replacement in the correct size.

Quote:

Originally Posted by cny-bikeman

If there is a notch in the right side cup you would have to use a hammer and punch to remove the cone. If there is none then removal is not practical. The wear on the cups or cones just makes them run smoother, but any pitting is a reason for replacement. If the cones are not pitted get new cups and caged bearings and reassemble. If the right cone is shot and not removable I don't think it's worth putting money into a new crankset.

Okay, thanks Pompiere! I'm cleaning it up right now and will reassemble.
After looking at the cup (partially) cleaned up, it does appear like it was factory made that way on the lip of the cup so it wasn't really worn down.

CNY - the cone, bearings, and cups look great (except for that minor taper of the lip) so I'm good to go.

Thanks again to the both of you!