8 speed with a 9 speed
03-29-18 | 01:26 PM
#1
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8 speed with a 9 speed
I have a shimano deore rear derailleur and I wanna get a 9 speed front derailleur(using my old one currently)..in a few months I wanna upgrade to 9 but you think I'd have a problem running it on an 8 speed cassette till then?..I had some chain rub with the current derailleur so I wanna change the front derailleur out..
03-29-18 | 01:36 PM
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Do you even need a new FD if you upgrade your shifters and RD to 9?
Front derailleurs don't have 8 or 9 speeds (or 10 or 11 for that matter). They have 2 or 3 (double or triple). It might need a little trimming or adjusting with the high and low limit screws if the 9 speed chain is narrower, but I would be surprised if it didn't work with the new shifter.
Edit: generally you fix chain rub by adjusting the FD, not throwing it out and getting a new one.
Front derailleurs don't have 8 or 9 speeds (or 10 or 11 for that matter). They have 2 or 3 (double or triple). It might need a little trimming or adjusting with the high and low limit screws if the 9 speed chain is narrower, but I would be surprised if it didn't work with the new shifter.
Edit: generally you fix chain rub by adjusting the FD, not throwing it out and getting a new one.
03-29-18 | 01:55 PM
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Do you even need a new FD if you upgrade your shifters and RD to 9?
Front derailleurs don't have 8 or 9 speeds (or 10 or 11 for that matter). They have 2 or 3 (double or triple). It might need a little trimming or adjusting with the high and low limit screws if the 9 speed chain is narrower, but I would be surprised if it didn't work with the new shifter.
Edit: generally you fix chain rub by adjusting the FD, not throwing it out and getting a new one.
Front derailleurs don't have 8 or 9 speeds (or 10 or 11 for that matter). They have 2 or 3 (double or triple). It might need a little trimming or adjusting with the high and low limit screws if the 9 speed chain is narrower, but I would be surprised if it didn't work with the new shifter.
Edit: generally you fix chain rub by adjusting the FD, not throwing it out and getting a new one.
03-29-18 | 01:58 PM
#4
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Do you even need a new FD if you upgrade your shifters and RD to 9?
Front derailleurs don't have 8 or 9 speeds (or 10 or 11 for that matter). They have 2 or 3 (double or triple). It might need a little trimming or adjusting with the high and low limit screws if the 9 speed chain is narrower, but I would be surprised if it didn't work with the new shifter.
Edit: generally you fix chain rub by adjusting the FD, not throwing it out and getting a new one.
Front derailleurs don't have 8 or 9 speeds (or 10 or 11 for that matter). They have 2 or 3 (double or triple). It might need a little trimming or adjusting with the high and low limit screws if the 9 speed chain is narrower, but I would be surprised if it didn't work with the new shifter.
Edit: generally you fix chain rub by adjusting the FD, not throwing it out and getting a new one.
03-29-18 | 02:00 PM
#5
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Do you even need a new FD if you upgrade your shifters and RD to 9?
Front derailleurs don't have 8 or 9 speeds (or 10 or 11 for that matter). They have 2 or 3 (double or triple). It might need a little trimming or adjusting with the high and low limit screws if the 9 speed chain is narrower, but I would be surprised if it didn't work with the new shifter.
Edit: generally you fix chain rub by adjusting the FD, not throwing it out and getting a new one.
Front derailleurs don't have 8 or 9 speeds (or 10 or 11 for that matter). They have 2 or 3 (double or triple). It might need a little trimming or adjusting with the high and low limit screws if the 9 speed chain is narrower, but I would be surprised if it didn't work with the new shifter.
Edit: generally you fix chain rub by adjusting the FD, not throwing it out and getting a new one.
03-29-18 | 02:09 PM
#6
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See what Sheldon Brown had to say on the subject:
https://www.sheldonbrown.com/speeds.html
Originally Posted by Sheldon Brown
Chainrings/Cranks
Old Chainrings, New Chains
There is a lot of confusion about the compatibility of narrow 9- and 10-speed chains with older cranksets. Shimano says you should replace the inner chainring(s) with specially designated 9- or 10-speed ones, but then they're all too eager to sell you stuff, whether you need it or not.
These chainrings have the teeth slightly farther to the right than the older chainrings to work a little better with the narrower chains. There is no difference whatever in the crank spiders.
The manufacturers also are concerned about clueless users. The worst-case scenario is that you will be riding along with the bike in its highest gear (large front, small rear) and then for some bizarre reason shift down in front before downshifting in the back. (There is no shift pattern in which it is reasonable to shift in this sequence.) [Not with a 9- or 10-speed cassette, to be sure -- John Allen] If you do shift this way, there's a small chance that the chain might "skate" over the edges of the teeth for maybe half a turn.
In practice this "problem" almost never materializes. Many, many cyclists are using 9- and 10-speed chains with older cranksets and having no problems whatever.
New Chainrings, Old Chains
Going the other direction, using wider chains with chainrings intended for narrower chains is not generally a major problem if there's only a one- or two- generation difference. The only problem you might run into is that the chain will be more liable to rub on the inside of the bigger chainrings in the small/small crossover gears, gears you shouldn't be using in any case.
Old Chainrings, New Chains
There is a lot of confusion about the compatibility of narrow 9- and 10-speed chains with older cranksets. Shimano says you should replace the inner chainring(s) with specially designated 9- or 10-speed ones, but then they're all too eager to sell you stuff, whether you need it or not.
These chainrings have the teeth slightly farther to the right than the older chainrings to work a little better with the narrower chains. There is no difference whatever in the crank spiders.
The manufacturers also are concerned about clueless users. The worst-case scenario is that you will be riding along with the bike in its highest gear (large front, small rear) and then for some bizarre reason shift down in front before downshifting in the back. (There is no shift pattern in which it is reasonable to shift in this sequence.) [Not with a 9- or 10-speed cassette, to be sure -- John Allen] If you do shift this way, there's a small chance that the chain might "skate" over the edges of the teeth for maybe half a turn.
In practice this "problem" almost never materializes. Many, many cyclists are using 9- and 10-speed chains with older cranksets and having no problems whatever.
New Chainrings, Old Chains
Going the other direction, using wider chains with chainrings intended for narrower chains is not generally a major problem if there's only a one- or two- generation difference. The only problem you might run into is that the chain will be more liable to rub on the inside of the bigger chainrings in the small/small crossover gears, gears you shouldn't be using in any case.
03-29-18 | 02:14 PM
#7
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If anything, a 9 speed FD may be less tolerant of cross chaining than an 8 speed. A 9 speed chain will work with your 8 speed other stuff, might give you a little more clearance if you insist on using marginal gearing combos.
03-30-18 | 05:22 PM
#8
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I run an 8 speed triple FD on my 9 speed. I have no real issues. Sometimes shifting from low to middle requires a click and a tiny bit extra, but everything else is flawless. A 9sp RD will work on an 8 speed cog and shifter. Just a little extra adjustments on the limit screws.
I've had matched all new components with chain rub. I've done mismached on others with no rub.
I've had matched all new components with chain rub. I've done mismached on others with no rub.
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