RAYZIE

eyo, hope all is doing well. anyways i'll get down straight to the matter.

currently running 46/17, and wanted to change/increase to a 48/17 but i had a few questions.

bike chain right now has about 1000km on it, how bad would it effect my chain if i were to replace the crank/chainring from 46 to 48? (this is probably a stupid question but i'm askin anyways) on that being said i don't mind buying a new chain but i'm not too sure exactly how long ss chains usually last (izumi super toughness); so i'm riding it til it gives me problems, my rides aren't as buttery anymore, or it finally snaps (hmm i wonder).

other factors i should keep in mind/thought? i know that the bike part market is sky-high so i was thinking on holding back on installing the 48t after i end up getting a new bottom bracket (which is due anytime soon).

any ideas/comments will be appreciated.

cheers.

Mikefule

46/17 = 2.705
48/17 = 2.824
46/16 = 2.875

2.875/2.824 = 1.018.

There is less than 2% difference between 48/17 and 46/16.

Personally, I'd go for the 1t smaller sprocket than the 2t bigger chainring.

As for the chain, the price of a new SS chain is almost negligible. If you're worried, just replace it.

ClydeClydeson

Theoretically, larger cogs/chainrings cause less* wear and suffer from less* drag than smaller cogs/chainrings of the same ratio, all other things being equal.

Less = marginally, infinitesimally, probably unnoticeably less

79pmooney

I run an 1/8" Izumi Eco chain over EuroAsian cogs. 42 or 43 tooth chainrings. I swap cogs often and chainrings several times.per year. I don't even think twice about it. Change out the chains at 1/16" in 12" of "stretch". Buy new 16 and 17 tooth cogs periodically when new chains run rough on them. (15 -18 are my flat ground cogs. I only sometimes can ride the 15 and the 18 gets limited off season and post injury use.) At 20,000 miles, this is still working just fine. I can use any of my cogs (12 teeth to 24 teeth) and both chainrings still.

You are using a chain made to be used by very strong riders on the track where they change cogs and rings for events without thinking about it. Don't sweat it. 620 miles (1000 km) is nothing, That chain is brand new.

As an above poster said, changing cogs is a lot easier - if you have a proper chain whip, greased the threads when you put the cog on and have a "normal" ratio of upper body strength vs leg strength. (If fabled velodrome rider Nelson Vails did a standing start on my bike, no way are my arms ever unscrewing that cog!) I say "proper" chainwhip. You do not have to spend huge money for a name. Home depot 1X1/8" flatbar, some scrap chain, 3 holes and a little shockcord. A touch of grinding/filing to narrow the bar at the chain ends and you are in business. Mine's gone 40 years. I've replaced the chain once.

Don't over think this. Change gears as your body and riding demand. Keep chains under 1/16" of stretch. Replace cogs when new chains run rough on them. Easy, peasy. Even buying good stuff, cheap in the long haul and not a whole lot of work. Or brain fatigue.

RAYZIE

thanks so much y'all.

I know there's a not than 2% difference between 48/17 and 46/16, but I did notice the small difference when I went down (i probably sound so whack).

cheers guys.

Rolla

/thread