Join Date: May 2008
Location: Royal Palm Beach, Florida
Bikes: 2006 Co-Motion Roadster (Flat Bars, Discs, Carbon Fork), Some 1/2 bikes and a couple of KTM's
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
I've been doing more homework on this as time permits.
Information from here is great.
In regards to our front setup, as I mentioned, the bike has a triple chainring front, with an Ultegra front der (Part Number FD-6503) and a Grip Shift Extreme, index type front shifter designed for off road.
At the present time it works. The shifter does not have the proper cable pull for this front der. But it does work, with a heavy cable pull and fast dowshifts.
I checked and compared the actuation arm length of this FD-6503 Ultegra front to a mountain front and they definitely have a difference.The Ultegra has a 14mm long cable attatch arm while the off road type is 20mm. This accounts for the heavy pull and fast down shifts.
The odd part of all this is my Kestrel roadbike with 600 Front Der has the longer arm similar to a MTB, but it has two positions to clamp the cable. Depending upon which slot is used, inboard or outboard of the cable clamp bolt, one will make it actuate at 14mm like the Ultegra in question (which is where it's clamped now on the Kestrel) and the other cable slot will space it at 20mm like a MTB.
This why I believe some have minimal or no issues and why our tandem with Ultegra / Grip shift is the fastest actuating, front shifting bike I've ever ridden. My current Ultegra does not have the two cable clamping positions, while others posting here do have two clamp slots.
With a 54 tooth big ring it leaves a few options.
First is just ride it as is and deal with it. This includes normally over shifting to the inner on account of very little shifter movement for full travel of the front der. Plus a heavy pull to wind the front der on upshifts.
Second is to find another front der with this double cable clamp position, like my 600, and replace the front der. The big question is which model has this capability. Any ideas?
Last edited by PMK; 11-05-08 at 05:26 AM.