New cassette ...(derailleur and chain?)

devonp

thinking of changing cassette from 11-28 on a Shimano 6800 to an 11-32 6800

anyone know if the current cage will take this? or will i need a new one and or chain too ?

cheers

Pinch Flat

devonp wrote: »

thinking of changing cassette from 11-28 on a Shimano 6800 to an 11-32 6800

anyone know if the current cage will take this? or will i need a new one and or chain too ?

cheers

Looks like 32-12 according to shimano

http://www.shimano.com/content/sac-bike/en/home/components11/road/ultegra1/rd-6800-gs.html

Your chain will be slightly shorter given it has to travel around a bigger rear cog in the lowest gear. I'd see how the chain looks when in the lowest gear - if the derailleur is pulling forward, a correctly sized chain may be required.

devonp

so biggest stretch would be from 50T front to 32T rear

if i need a new chain can anyone give me an idea if i will need to get a 118 link chain, (11 spd of course,) KMC with a missing link would be best i reckon...?
and a chain breaker to get the old one off and remove links from new chain

cheers

iwillhtfu

devonp wrote: »

so biggest stretch would be from 50T front to 32T rear

if i need a new chain can anyone give me an idea if i will need to get a 118 link chain, (11 spd of course,) KMC with a missing link would be best i reckon...?
and a chain breaker to get the old one off and remove links from new chain

cheers

The biggest stretch should only be between your 34/32 you're cross chaining and rubbing on your derailleurs if you're using the top few cogs in the outer ring.

Wishbone Ash

iwillhtfu wrote: »

The biggest stretch should only be between your 34/32 you're cross chaining and rubbing on your derailleurs if you're using the top few cogs in the outer ring.

Leaving cross chaining aside, ideally it should be able to cover both extremes - the 50/32 and 34/11. Otherwise you could have an awkward mechanical should either of these gearing situations be accidentally selected.

devonp

ok thanks
i understand that i wouldn't actually use this combo but the current chain would have to be able to do this while on the bike stand?? otherwise i would need a new chain....is this correct??
sry about the noob mechanical questions

Wishbone Ash

Well a bike shop will never fit a chain or cage which won't cover both extremes. New chains generally cover 50/32 as far as I know.

Carawaystick

Usually a new cassette = new chain, unless the existing ones are very recent. A worn chain will wear a cassette much faster.

You always think you will never go 50x30/32/28/most teeth back cog, but every now and then you will, to keep pace just to top over a hill or when you think you're in a taller gear and drop gears as you approach a stop or red light.

devonp

with the new cassette 11-32t and properly sized chain all is good except in the lowest gear ie small 34t chainring to 32t sprocket...where it grinds a lot ...(fine in the 28t)
experimented with B screw ..better ...but still grinding
i assume i have a ultegra 6800 SS cage and will need a 6800 GS cage ??:o
(originally had 11-28t)

how difficult is it to fit a new derailleur ?

devonp

just one bump ...anyone?

before i buy a GS derailleur or bring to LBS

jon1981

This thread describes your problem... seems some guy got it work with a SS


http://www.bikeradar.com/forums/viewtopic.php?t=12961056&

Though opinion seems to be very mixed on it from what I can find , with most recommending GS