Originally Posted by
pataspen
I am considering switching my old touring bike from a triple to a double compact crankset. Currently I have an Ultegra triple with an internal bottom bracket.
Searching eBay for compact cranks there are options for cranks which utilize both internal and external bottom brackets.
Am I correct in assuming I can easily convert an internal BB to an external one?
If so, would it be better than an internal BB?
I recently pedaled from Alaska to the tip of Baja and I'm foolishly considering riding the rest of the way to Tierra del Fuego some day. Assuming I'll have to replace the BB or crank at some point, would an internal or external BB be easier to replace in Latin America?
Finally, does anyone have any good experience or suggestions for reliable BB/compact cranks for a 12,000 mile tour? Are any better or more popular, I.e. Hollowtech, MegaExo, etc?
Sorry about so many questions, but I'd sure appreciate any help.
Thanks,
Pat
I don't know what people do to kill their bearings but, frankly, I've never worn out a cartridge type bottom bracket of any kind...internal or external. I use both and have them on bikes that are used for daily commuting year around. Touring babies them comparatively.
I don't know if one or the other would be easier to replace in Latin America. If you got an external bearing crank and used the appropriate Phil Wood bottom bracket, I don't you'd need to worry about it. But the bearings on the Phil unit are replaceable with a standard bearing that should be readily available most anywhere that has cars.
Consider, also, how you would remove and replace an internal bearing BB. You'll need a wrench to remove the crank bolts. Either an 8mm allen wench or a 14mm socket. You have to have something to pull the cranks off. Can you find that readily in Latin America? There are integral crank pullers that you can use on square taper cranks but, in my experience, they take a 6mm allen wrench that just isn't up to the torque needed to remove the crank. Then you need a special tool to remove and replace the BB. Can you find that readily in Latin America? Then you are going to need a BB with the proper spindle length. How easy is that to find?
Compare that with an external bearing BB. If you go with Shimano...and, as much as it pains me to say this, you should...you'll need a 5 mm allen wrench to remove the crank. You can carry the tool to remove the external cups but you can also remove them with a large adjustable jaw pliers (aka Channelock) or a pipe wrench both of which you should be able to find just about anywhere. You might even be able to do it with a strap wrench or a belt. Removing and replacing the bearings might take a bit of Mcgyvering in the field but it would be doable.
Personally, I'd go external for the ease of installation and the ease of servicing in the rare case you'd need to do it.