Ultegra FD tire interference

corsu61 · #1 09-17-2021, 12:51 PM

I have an Ultegra 6800 front derailleur, clamp-on. Running 28mm tires. I’d like to go a bit wider with the tires but the clearance is already tight between the arm of the derailleur and the tire when I’m in the big chainring. A little research shows the 6800 series front derailleur has an especially long arm. My question, do I need to get a new derailleur (ultegra 8000 or DA 9000) or should I be looking at the angle I have the derailleur clamped to the tube?

Dude · #2 09-17-2021, 01:16 PM

New derailleur, sorry. I had a similar issue on another bike.

Big Dan · #3 09-17-2021, 01:29 PM

Yeah the newer style (8000) usually solves this issue.

corsu61 · #4 09-17-2021, 01:43 PM

Thanks! Follow up question…..why???? Seems like obviously terrible design without any benefit.

prototoast · #5 09-17-2021, 01:50 PM

Quote:

Originally Posted by corsu61

Thanks! Follow up question…..why???? Seems like obviously terrible design without any benefit.

I believe the original intention was that the longer arm gave more power to front shifts.

But yes, it was a bad design, which is why they abandoned it in the next generation, and even released an updated 5800 front that didn't have the long arm. So I think it's safe to conclude that this was just a bad design and screw up from Shimano.

tuxbailey · #6 09-17-2021, 02:14 PM

Same thing happened to me. I had to get the R8000 FD to prevent contact with 28c tires.