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 Post subject: SRAM force and FD-7800
PostPosted: Sun Feb 19, 2012 6:40 pm 
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Joined: Wed Dec 07, 2011 1:26 am
Posts: 414
Location: California's country side
So.. I put this together (2011 force + FD-7800), from my reseach the throw ratio is compatible.

It works fine, and it is not picky on the tension like SRAM FD

But I must say it is stiff to operate the lever, on the workstand sometimes I can't get the FD to get to the high limit , on the road it is OK and I rotated the lever off the bar. had to install the shifter clamp to almost 5nm.

I don't think the tension is too high, because the downshift trim still moves.

The chain drops to the small ring slowly, unlike the force, so the chain drop problem should be avoided.


Anyone with experience with SRAM lever and 7800/6600?


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 Post subject: SRAM force and FD-7800
Posted: Sun Feb 19, 2012 6:40 pm 


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PostPosted: Sun Feb 19, 2012 7:02 pm 
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Joined: Mon Oct 12, 2009 6:36 pm
Posts: 246
Lost my Force FD when another rider crashed into me during a race (very weird situation, it got stuck in my chainwheel).

So I had I 7800 FD lying around, installed it with a braze-on adapter. Worked fine, never had any issues with it, just put a Force FD back on because I like to keep everything one brand.


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PostPosted: Sun Feb 19, 2012 7:09 pm 
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Joined: Mon Aug 08, 2011 5:46 pm
Posts: 59
I don't have 6600 or 7800, but am using a 6700 FD with some red shifters; nothing feels out of the ordinary for me and I'm happy with the performance. I wish Sram shifters didn't have the trim feature though or if it did that it functioned like campys. Only gripe. I've spread the gate a bit on my FD to eliminate chain rub so now I have a trim feature in the large ring that does me no good. If ever I experience extreme boredom I may open up the shifter and file off that notch and eliminate the trim. Or just live with it. It's relatively flat here, front shifts are rare.


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PostPosted: Mon Feb 20, 2012 1:05 am 
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Joined: Wed Dec 07, 2011 1:26 am
Posts: 414
Location: California's country side
I just road tested some more and it is working OK, it's a little stiffer but it works well. Dropping into the small ring is accurate and gentle now, because the shimano spring is not wounded as tight.

I also put a 3M matte film over the side of the frame in case the chain throws. When I used the Force FD on my frame it is a possibility and I was so scared everytime I downshift.. even with the chain catcher it managed to throw it between the frame and the ring.


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PostPosted: Mon Feb 20, 2012 4:45 am 
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Joined: Wed Dec 14, 2011 4:37 pm
Posts: 87
SRAM + prior gen 10sp Shimano is the bomb diggity for consistent, spot-on shifting.


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PostPosted: Mon Feb 20, 2012 5:00 am 
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Joined: Mon Aug 29, 2011 8:55 pm
Posts: 167
Location: New Jersey
+1 I have a 6600 FD with my red group and its perfect. Is your 7800 FD new? If its not lubricating the pivot points may make the lever throw easier.


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PostPosted: Mon Feb 20, 2012 5:53 am 
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Joined: Wed Feb 15, 2012 7:11 am
Posts: 31
One of my bikes has a 6600 FD and another has Force, but both have Rival shifters. The bike with the Ultegra FD requires more force at the lever. When pushing each derailleur against its spring, the 6600's spring feels at least twice as stiff as the Force FD. When I used the Ultegra FD with a matching 6600 lever, it only required a light force. SRAM designed their system to require less travel to make a shift, and complimented that with a softer spring at the derailleur to keep shifting force in check. Shimano shifters require a greater travel at the lever to make the shift.

The issue you are experiencing is just a result of using a SRAM lever and a Shimano derailleur. In the end it works because the cable pull is the same, but requires more force at the shift lever.


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Posted: Mon Feb 20, 2012 5:53 am 


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PostPosted: Mon Feb 20, 2012 6:12 am 
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Joined: Wed Dec 07, 2011 1:26 am
Posts: 414
Location: California's country side
dwb wrote:
One of my bikes has a 6600 FD and another has Force, but both have Rival shifters. The bike with the Ultegra FD requires more force at the lever. When pushing each derailleur against its spring, the 6600's spring feels at least twice as stiff as the Force FD. When I used the Ultegra FD with a matching 6600 lever, it only required a light force. SRAM designed their system to require less travel to make a shift, and complimented that with a softer spring at the derailleur to keep shifting force in check. Shimano shifters require a greater travel at the lever to make the shift.

The issue you are experiencing is just a result of using a SRAM lever and a Shimano derailleur. In the end it works because the cable pull is the same, but requires more force at the shift lever.


Great explaination, thanks..


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