Ultegra Hydraulic Di2 shifter not springing back to neutral quickly.....any advice?

Triathlon Forum
1

Got a sweet deal on an almost new Trek Madone SLR Speed…first road bike with disc brakes…
Unpacked it over the weekend and one shifter is super responsive and springs back to neutral rapidly, the other shifter (for the rear brake) just feels spongey, if I go to pull on the brakes immediately after the last actuation there is a massive amount of “dead space” before there is any resistance etc, it does not spring back to neutral like the other shifter and just feels odd.
Are there any known issues? Any easy fixes? Anything I can try? We go away for a week in 48 hours and I had planned to take this bike away travelling and cannot get it to a shop to look at between now and then…

2

Whenever I see “spongey” my mind goes “bleed the brakes”.

Have you tried that / asked a shop to do it?
(note: if you want to do it yourself you’ll probably need the basic Shimano bleed kit)

3

This may sound odd but Loosen shifter clamp bolt completely and see if lever returns.

4

Whenever I see “spongey” my mind goes “bleed the brakes”.

Have you tried that / asked a shop to do it?
(note: if you want to do it yourself you’ll probably need the basic Shimano bleed kit)

Thanks, I was thinking that would be a sensible thing to do but I would need the kit and a youtube video! Am not sure if my local shops sell the kits…will check…the shops are all booked up at the moment…one nice thing about COVID is that bike sales are through the roof here…

5

This may sound odd but Loosen shifter clamp bolt completely and see if lever returns.

OK that does sound odd but I will try that anyway…nothing to lose!

6

This may sound odd but Loosen shifter clamp bolt completely and see if lever returns.

Okay VJL…you win the SlowTwitch appreciation award for today. I loosened the clamp bolt…shifter works perfectly now…tightened it up again and it is all good now. WTF!!! Any ideas what can cause it to do that just with the clamping??

7

This may sound odd but Loosen shifter clamp bolt completely and see if lever returns.

Okay VJL…you win the SlowTwitch appreciation award for today. I loosened the clamp bolt…shifter works perfectly now…tightened it up again and it is all good now. WTF!!! Any ideas what can cause it to do that just with the clamping??

yes, inquiry minds want to know…

8

My guess is overtightening clamp bolt distorts housing and interferes with piston movement. I use 3 or 4 NM max, any more and mine is slow to return.

9

Thanks for the useful tip. Never thought about this. Shimano recommends 6-8 nm of torque at the shifter clamp, but I’ve always gone with between 3-4 nm (as you mentioned), simply because any more force seems unnecessary (shifters are already firmly held in place)