I have changed the bottom bracket for an old 122mm cup and cone for a cartridge bottom bracket of the same size but after much adjustment I can't get the infernal machine to change gear smoothly. the chainline is terrible in both the inner and outer ring and it seems to skip a gear on the way up to the largest cog on the back to add to this it won't go onto the largest rear cog on either of the front chainrings is the BB to big for a shimano sora double. their also seems to be plenty of space (about 2 centimetres) between the crank arm and chainstay.
I have changed the bottom bracket for an old 122mm cup and cone for a cartridge bottom bracket of the same size but after much adjustment I can't get the infernal machine to change gear smoothly. the chainline is terrible in both the inner and outer ring and it seems to skip a gear on the way up to the largest cog on the back to add to this it won't go onto the largest rear cog on either of the front chainrings is the BB to big for a shimano sora double. their also seems to be plenty of space (about 2 centimetres) between the crank arm and chainstay.
cheers Jon_H
No Sora cup and cone was ever made and I'll check, but I think the square taper BB length for Sora is much shorter, like about 108mm/110mm. As for shifting in the rear, not rerally related to the front. Cable underneath the rear der cable fixing bolt? Not over it or thru the plate somehow?
"Qui si parla Campagnolo" <[email hidden]> wrote in message news:[email hidden]...
Quoted message said:
Jon_H said:
I have changed the bottom bracket for an old 122mm cup and cone for a cartridge bottom bracket of the same size but after much adjustment I
can't
Quoted message said:
Quoted message said:
get the infernal machine to change gear smoothly. the chainline is
terrible
Quoted message said:
Quoted message said:
in both the inner and outer ring and it seems to skip a gear on the way
up
Quoted message said:
Quoted message said:
to the largest cog on the back to add to this it won't go onto the
largest
Quoted message said:
Quoted message said:
rear cog on either of the front chainrings is the BB to big for a
shimano
Quoted message said:
Quoted message said:
sora double. their also seems to be plenty of space (about 2
centimetres)
Quoted message said:
Quoted message said:
between the crank arm and chainstay.
cheers Jon_H
No Sora cup and cone was ever made and I'll check, but I think the square taper BB length for Sora is much shorter, like about 108mm/110mm. As for shifting in the rear, not rerally related to the front. Cable underneath the rear der cable fixing bolt? Not over it or thru the plate somehow?
It wasn't a sora cup and cone fitted just a no-name part that came with the bike frame. it's a second hand bike so I don't know the history behind it . thanks for the advice I'll probably go with a shorter length BB cheers Jon_H
I have changed the bottom bracket for an old 122mm cup and cone for a cartridge bottom bracket of the same size but after much adjustment I can't get the infernal machine to change gear smoothly. the chainline is terrible in both the inner and outer ring and it seems to skip a gear on the way up to the largest cog on the back to add to this it won't go onto the largest rear cog on either of the front chainrings is the BB to big for a shimano sora double. their also seems to be plenty of space (about 2 centimetres) between the crank arm and chainstay.
cheers Jon_H
The problems with the rear are not necessarily related to chainline BUT I think Sora square taper BB spindle should be in the 110mm length, not 122.5. As for the rear der...cable underneath the fixing bolt? Not above or thru the plate?
I have changed the bottom bracket for an old 122mm cup and cone for a cartridge bottom bracket of the same size but after much adjustment I can't get the infernal machine to change gear smoothly. the chainline is terrible in both the inner and outer ring and it seems to skip a gear on the way up to the largest cog on the back to add to this it won't go onto the largest rear cog on either of the front chainrings is the BB to big for a shimano sora double. their also seems to be plenty of space (about 2 centimetres) between the crank arm and chainstay.
What crank and which BB ? If you had a Stronglight triple with a 123 asymmetric spindle but changed to a Shimano 122 cartidge BB, symmetric but a different taper section, something like that would result. -- Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971
"A Muzi" <[email hidden]> wrote in message news:[email hidden]...
Quoted message said:
Jon_H said:
I have changed the bottom bracket for an old 122mm cup and cone for a cartridge bottom bracket of the same size but after much adjustment I
can't
Quoted message said:
Quoted message said:
get the infernal machine to change gear smoothly. the chainline is
terrible
Quoted message said:
Quoted message said:
in both the inner and outer ring and it seems to skip a gear on the way
up
Quoted message said:
Quoted message said:
to the largest cog on the back to add to this it won't go onto the
largest
Quoted message said:
Quoted message said:
rear cog on either of the front chainrings is the BB to big for a
shimano
Quoted message said:
Quoted message said:
sora double. their also seems to be plenty of space (about 2
centimetres)
Quoted message said:
Quoted message said:
between the crank arm and chainstay.
What crank and which BB ? If you had a Stronglight triple with a 123 asymmetric spindle but changed to a Shimano 122 cartidge BB, symmetric but a different taper section, something like that would result. -- Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971
The crank is a shimano sora double and the bottom bracket is a UN52/53 122mm it doesn't seem quite right as the front mech required quite a hefty adjustment to get it to move to the big ring.
The crank is a shimano sora double and the bottom bracket is a UN52/53 122mm it doesn't seem quite right as the front mech required quite a hefty adjustment to get it to move to the big ring.
cheers Jon_H
Sounds like your 122 mm spindle is too long! Sheldon's database calls for a 110 mm spindle if your Dora double has a square taper, or a 113 mm spindle if splined: http://www.sheldonbrown.com/bbsize.html#sora
You can usually find the model number (e.g. FC-3300, FC-3301) marked on the back side of the crank.
The crank is a shimano sora double and the bottom bracket is a UN52/53 122mm it doesn't seem quite right as the front mech required quite a hefty adjustment to get it to move to the big ring.
cheers Jon_H
Sounds like your 122 mm spindle is too long! Sheldon's database calls for a 110 mm spindle if your Dora double has a square taper, or a 113 mm spindle if splined: http://www.sheldonbrown.com/bbsize.html#sora
You can usually find the model number (e.g. FC-3300, FC-3301) marked on the back side of the crank.
"Qui si parla Campagnolo" <[email hidden]> wrote in message news:[email hidden]...
Quoted message said:
Quoted message said:
Jon_H said:
The crank is a shimano sora double and the bottom bracket is a UN52/53
122mm
Quoted message said:
Quoted message said:
Quoted message said:
it doesn't seem quite right as the front mech required quite a hefty adjustment to get it to move to the big ring.
cheers Jon_H
Sounds like your 122 mm spindle is too long! Sheldon's database calls for a 110 mm spindle if your Dora double has a square taper, or a 113 mm spindle if splined: http://www.sheldonbrown.com/bbsize.html#sora
You can usually find the model number (e.g. FC-3300, FC-3301) marked on the back side of the crank.
109.5 for the octalink Sora...
Thanks for all the advice, its a square taper and I have ordered a 110mm BB and it should arrive tomorrow.
