Do Shimano Sora Shifters work with RX 100 7spd
#1
Senior Member
Thread Starter
Join Date: Jun 2007
Location: Coral Springs, FL
Posts: 197
Bikes: Specialized Allez (2007); Fuji Finest (2002); Trek 1100 (1994); Giant Iguana
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Do Shimano Sora Shifters work with RX 100 7spd
I have a set of Shimano Sora (8 spd) on a bike that I wrecked and I'm thinking of moving it to my old college era bike - a Trek 1100 with RX 100 derailleurs and 7 speed cassette. They are both designed for triple cranks. Will this work? Do I just have to set the limit screws?
Thanks a lot.
Thanks a lot.
#3
Senior Member
Join Date: Feb 2008
Location: Research Triangle, NC
Posts: 87
Bikes: '70 Leopard (Swiss), '70 Raleigh Super Course, '74 Raleigh Super Course II, '73 Raleigh Grand Prix, Schwinn Montague folder, C-dale M-300, C-dale M-400, C-dale R-900, C-dale CAAD-3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Alas, it will not. The spacing between the cogs is not much individually but when you multiply it x7, you are going to have some really noisy shifting at either end of the range.
But, check that rear wheel - is that a 7-speed cassette or freewheel? I know that Shimano makes a very inexpensive 8-speed freewheel intended for folks seeking to upgrade to the Sora brifter setup you have. Last one I saw in a shop was only $14. Even an 8-speed cassette can be had cheaply if you hit the web and use a "deal-finder" like Qbike.com to hunt them.
But, check that rear wheel - is that a 7-speed cassette or freewheel? I know that Shimano makes a very inexpensive 8-speed freewheel intended for folks seeking to upgrade to the Sora brifter setup you have. Last one I saw in a shop was only $14. Even an 8-speed cassette can be had cheaply if you hit the web and use a "deal-finder" like Qbike.com to hunt them.
#4
Cat 6
Join Date: Dec 2007
Location: Mountain Brook, AL
Posts: 7,482
Mentioned: 27 Post(s)
Tagged: 0 Thread(s)
Quoted: 500 Post(s)
Liked 183 Times
in
118 Posts
Alas, it will not. The spacing between the cogs is not much individually but when you multiply it x7, you are going to have some really noisy shifting at either end of the range.
But, check that rear wheel - is that a 7-speed cassette or freewheel? I know that Shimano makes a very inexpensive 8-speed freewheel intended for folks seeking to upgrade to the Sora brifter setup you have. Last one I saw in a shop was only $14. Even an 8-speed cassette can be had cheaply if you hit the web and use a "deal-finder" like Qbike.com to hunt them.
But, check that rear wheel - is that a 7-speed cassette or freewheel? I know that Shimano makes a very inexpensive 8-speed freewheel intended for folks seeking to upgrade to the Sora brifter setup you have. Last one I saw in a shop was only $14. Even an 8-speed cassette can be had cheaply if you hit the web and use a "deal-finder" like Qbike.com to hunt them.
Back to the original question. When you set the system up use the middle (4th) cog to set as your "zero offset" position. If you do this then on the largest and smallest cog your "mis-shift" offset will only be 3*0.2mm = 0.6mm
__________________
72 Frejus (for sale), Holdsworth Record (for sale), special CNC & Gitane Interclub / 74 Italvega NR (for sale) / c80 French / 82 Raleigh Intl MkII f&f (for sale)/ 83 Trek 620 (for sale)/ 84 Bruce Gordon Chinook (for sale)/ 85 Ron Cooper / 87 Centurion IM MV (for sale) / 03 Casati Dardo / 08 BF IRO / 09 Dogma FPX / 09 Giant TCX0 / 10 Vassago Fisticuff
72 Frejus (for sale), Holdsworth Record (for sale), special CNC & Gitane Interclub / 74 Italvega NR (for sale) / c80 French / 82 Raleigh Intl MkII f&f (for sale)/ 83 Trek 620 (for sale)/ 84 Bruce Gordon Chinook (for sale)/ 85 Ron Cooper / 87 Centurion IM MV (for sale) / 03 Casati Dardo / 08 BF IRO / 09 Dogma FPX / 09 Giant TCX0 / 10 Vassago Fisticuff
#5
Senior Member
Join Date: Feb 2008
Location: Research Triangle, NC
Posts: 87
Bikes: '70 Leopard (Swiss), '70 Raleigh Super Course, '74 Raleigh Super Course II, '73 Raleigh Grand Prix, Schwinn Montague folder, C-dale M-300, C-dale M-400, C-dale R-900, C-dale CAAD-3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
#6
Senior Member
Join Date: Mar 2005
Location: Pinole, CA, USA
Posts: 17,392
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 443 Post(s)
Likes: 0
Liked 27 Times
in
25 Posts
It will work just fine. Take it from someone who has actually done it. The difference in spacing is not significant.
An 8 speed cassette on a 7 speed hub will not work at all.
An 8 speed cassette on a 7 speed hub will not work at all.
#7
Low car diet
Join Date: Aug 2007
Location: Corvallis, OR, USA
Posts: 2,407
Bikes: 2006 Windsor Dover w/105, 2007 GT Avalanche w/XT, 1995 Trek 820 setup for touring, 201? Yeah single-speed folder, 199? Huffy tandem.
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 4 Times
in
4 Posts
See the "Alternate Cable Routing" section https://www.sheldonbrown.com/dura-ace.html#indexing
It says it will work for 10-speed shifters w/9-speed cassette. I wonder if it would help with 8-speed shifter/7-speed cassette?
Check if it is really a 7-speed cassette. If you see a 4.5mm spacer behind the cassette, it should be 8-speed compatible. It's likely 7-speed only, but might as well check.
It says it will work for 10-speed shifters w/9-speed cassette. I wonder if it would help with 8-speed shifter/7-speed cassette?
Check if it is really a 7-speed cassette. If you see a 4.5mm spacer behind the cassette, it should be 8-speed compatible. It's likely 7-speed only, but might as well check.
#8
cycles per second
Join Date: Oct 2003
Location: Minnesota
Posts: 1,930
Bikes: Early 1980's Ishiwata 022 steel sport/touring, 1986 Vitus 979, 1988 DiamondBack Apex, 1997 Softride PowerWing 700, 2001 Trek OCLV 110
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Liked 71 Times
in
48 Posts
+1 Okay, I haven't actually done it but I have a friend who has. If your drivetrain is finicky and doesn't shift well, you can replace the 7-speed cassette spacers with 8-speed spacers (with perhaps a 1mm spacer behind it all if needed to snug down the cassette) and, voila, you have 8-speed spacing on your 7-speed cassette.
#9
Senior Member
Thread Starter
Join Date: Jun 2007
Location: Coral Springs, FL
Posts: 197
Bikes: Specialized Allez (2007); Fuji Finest (2002); Trek 1100 (1994); Giant Iguana
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Thanks for the help and ideas.
I also have an 8 spd cassette from the wrecked bike that could be used to help solve this problem. Does that add any additional/better solutions?
Thanks.
I also have an 8 spd cassette from the wrecked bike that could be used to help solve this problem. Does that add any additional/better solutions?
Thanks.
#10
Senior Member
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,656
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 2026 Post(s)
Likes: 0
Liked 1,096 Times
in
742 Posts
There are 8-speed freewheels available from Sun Race and these are quite cheap but problematic as the excess length makes them even more prone to causing broken axles then even 7 or 6-speed freewheels. Also, an 8-speed freewheel requires a 130 mm OLD hub and dropout width just like an 8-speed cassette hub.
#11
Senior Member
Join Date: Sep 2001
Location: Montreal
Posts: 6,521
Bikes: Peugeot Hybrid, Minelli Hybrid
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times
in
2 Posts
I have done Shedon Brown's alternate routing to make an 8 sp Sora shifter work with a 7sp cassette. However after 6 months the rim failed so I bought a new wheel with 8 sp hub.
#12
Really Old Senior Member
If you can't "transplant" the entire wheel from the wrecked bike, you would have to transplant the free hub BODY along with the 8 speed cassette. The 7 speed body is too short for an 8 speed cassette.
Gonzo Bob's idea should also work. You do have the spacers on the 8 speed cassette you could steel.
If it were me, I'd probably pick the method that gave me the most useful gears for my needs.
Gonzo Bob's idea should also work. You do have the spacers on the 8 speed cassette you could steel.
If it were me, I'd probably pick the method that gave me the most useful gears for my needs.
#13
Senior Member
Join Date: Mar 2005
Location: Pinole, CA, USA
Posts: 17,392
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 443 Post(s)
Likes: 0
Liked 27 Times
in
25 Posts
No alternate cable routing is needed to run 8 speed shifters with a 7 speed cassette or freewheel. If you don't believe me, read Sheldon Brown, or better yet, try it yourself.
#14
Senior Member
Join Date: Feb 2004
Location: St Peters, Missouri
Posts: 30,225
Bikes: Catrike 559 I own some others but they don't get ridden very much.
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 1572 Post(s)
Liked 643 Times
in
364 Posts
FWIW I've fiddled many times with mixing and matching 7 and 8-speed parts. I can get it to "kind of" work but never to my satisfaction. I guess that means that either I'm pickier than those other guys or a less adept mechanic.