Pete In Az

Do I need to play with the B screw and/or chain length?

The chain is new. It shifts fine, doesn't make any weird noises and there doesn't seem to be any slack in the chain even when I cross chained little to little (on the bike stand, I try not to do that on purpose while riding).

Also, how long does the lube on a new chain usually last?

Bill Kapaun

You don't NEED to.
I would.

Pete In Az

Why? Would it save on wear and tear on the freewheel?

Hendo252 

Don't confuse me with somebody that knows much, but I've always beleived that the goop that the factory puts on a new chain is for corrosion protection, not lubrication. So I've always thoroughly cleaned a new chain prior to installation and then applied the lube of my choice...

-Tom in SoCal.

FastJake

+1 to what Bill said. You don't actually need to do anything, but you could probably lose a link on the chain and loosen the b-tension screw quite a bit for "more precise" shifting (although I honestly don't know what difference it makes.) If you keep the chain the same length, you can always put the 14-34 freewheel back on without having to worry. How to determine chain length: https://sheldonbrown.com/derailer-adjustment.html#chain

How long does factory lube last? Depends what your riding conditions are. I've found that SRAM chains come coated in maple syrup which attracts every single dirt/dust/sand particle on the road. So before I ride with a new SRAM chain I wipe the outside down to clean off the goop, but leaving the lube on the inside of the chain still intact.

Pete In Az

I have a SRAM chain. You're right about the maple syrup. I cleaned off the outside. I was gust wondering about the inside. As viscous as it is I would think it would be good for quite a while but I could be wrong. I want to keep this chain as long as I can.

FastJake

Yeah it's really thick stuff. I keep it in there as long as possible, only dry wiping or wet wiping the chain until it just gets too dirty. At that point I clean the whole thing and the original lube is lost, but obviously it doesn't last forever (once it gets contaminated.)

Pete In Az

Ok. Thank you Jake. Oh, and as far as "precision shifting" goes. I'm riding a 2007 Raleigh Venture 3.0,a comfort bike. I believe the tolerances are a bit loose on it. Unless someone comes up with a good reason to fiddle with the B screw, I'm going to leave it alone. I might get lazy some day and go back to a 14-34.

Bill Kapaun

I'd adjust the B screw.
It should improve shifting a little bit and doesn't cost any $. You can't do much better than free!

Since you've gone to smaller cogs, the guide pulley is even further away than it should be.
Chances are, it was further away than it should be with the original FW.