Need Shimano Front Derailleur Help
08-05-08, 11:03 AM
#1
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Need Shimano Front Derailleur Help
I am building up a road bike for my wife and plan using a R600 compact crankset (50/34) with a SRAM 9-speed cassette. I recently ordered Tiagra derailleurs from Nashbar to complete the drivetrain. This is the front that I ordered:
https://www.nashbar.com/profile.cfm?c...t%20Derailleur
mainly because it said it was compact crank compatiple and had a multi-clamp that should work with the 31.8mm seat tube. But when I received it and opened it up it looked completely different than the picture, the clamp was for a 34.9mm tube and there were no shims or other provision to make it properly fit a smaller tube. Also, the instruction specifically list the maximum chainring difference as 15 or less, not the 16 that my (and most other?) compacts have.
I called Nashbar and talked to a tech who told me that 1)The picture on their website for that product is wrong and that the double which I need is longer slender like the one that I received. 2) They forgot to send the shims and he would send a set right out. And 3) that the one they send would in fact work fine with a 16t chainring spread.
So can anyone confirm or deny what I have been told? I don't have the rest of the parts yet to actually test it out.
Thanks, Steven.
https://www.nashbar.com/profile.cfm?c...t%20Derailleur
mainly because it said it was compact crank compatiple and had a multi-clamp that should work with the 31.8mm seat tube. But when I received it and opened it up it looked completely different than the picture, the clamp was for a 34.9mm tube and there were no shims or other provision to make it properly fit a smaller tube. Also, the instruction specifically list the maximum chainring difference as 15 or less, not the 16 that my (and most other?) compacts have.
I called Nashbar and talked to a tech who told me that 1)The picture on their website for that product is wrong and that the double which I need is longer slender like the one that I received. 2) They forgot to send the shims and he would send a set right out. And 3) that the one they send would in fact work fine with a 16t chainring spread.
So can anyone confirm or deny what I have been told? I don't have the rest of the parts yet to actually test it out.
Thanks, Steven.
08-05-08, 01:11 PM
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If she has shifting problems a good alternative may be to replace the 50t big ring with a 48 or 49 (110 BCD).
08-05-08, 01:51 PM
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It will work fine with the 16 tooth spread.
1. Shimano is very conservative with their max ratings which can almost always be beated by a tooth or 2
2. Shimano came late to the compact crankset party and took the time to make a crankset that was spec'd to work with the existing Shimano derailliurs without problem. Some of the other early compact cranks worked best with a special derailleur for the 16 tooth spread.
I believe that once you have the shims that you will be good to go.
1. Shimano is very conservative with their max ratings which can almost always be beated by a tooth or 2
2. Shimano came late to the compact crankset party and took the time to make a crankset that was spec'd to work with the existing Shimano derailliurs without problem. Some of the other early compact cranks worked best with a special derailleur for the 16 tooth spread.
I believe that once you have the shims that you will be good to go.
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