External Bearing BB (7800 crankset) with 7700 groupset?
04-08-10, 09:47 AM
#1
Full Member
Thread Starter
Join Date: Apr 2010
Location: Austin TX
Posts: 298
Bikes: '16 Cannondale Slate, '12 Fisher Cronus, '85 Pinarello Triatlon, '98 Sampson Z7 Pro Road Ti , '96 Merlin Titanium, '95 Cannondale V500, '72 Gitane TdF, ' 89 Merckx Corsa Extra, '85 Centurion Ironman pink/yellow, ' 85 1st gen Fuso.
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
External Bearing BB (7800 crankset) with 7700 groupset?
I have a bike with a full 7700 groupset on it, and I'm interested in switching the cranksetup over to something like the 7800 with external bearings. I read that the rings on 7800 are thinner for 10 spd chains, and that the rings are also slightly closer together on 7800 cranks vs 7700. I'm concerned with two things:
1) Will I have trouble throwing chains when dropping from the big ring down to the small ring running a 9 spd chain on the 7800 type crankset?
2) Will the external bearing setup push the location of the front rings out far enough that my 9 spd derailleur can't be adjusted out far enough to properly work?
Any feedback will be appreciated.
Thanks.
1) Will I have trouble throwing chains when dropping from the big ring down to the small ring running a 9 spd chain on the 7800 type crankset?
2) Will the external bearing setup push the location of the front rings out far enough that my 9 spd derailleur can't be adjusted out far enough to properly work?
Any feedback will be appreciated.
Thanks.
04-08-10, 09:49 AM
#2
Senior Member
Join Date: Jun 2007
Location: A Coffin Called Earth. or Toronto, ON
Posts: 12,257
Bikes: Bianchi, Miyata, Dahon, Rossin
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
no and no.
__________________
Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm
Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm
04-08-10, 10:19 AM
#3
Guest
Join Date: Jul 2008
Location: Grid Reference, SK
Posts: 3,768
Bikes: I never learned to ride a bike. It is my deepest shame.
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 6 Times
in
6 Posts
Agreed and agreed.
Throwing the chain will not happen if the lower end point on the front derailleur is set properly.
The cranks used with external bottom brackets are designed to be used with external bottom brackets and do not have the rings any further out than standard BBs. THe distance between the centre of the frame and the chainrings is standardized on road bikes to optimize chainline, and chainline has not changed between 9 and 10 speeds.
Last edited by LarDasse74; 04-08-10 at 10:22 AM.
Thread
Thread Starter
Forum
Replies
Last Post
interestor
Bicycle Mechanics
11
04-20-17 02:06 PM
