ZHVelo

So with my new wheelset the disc brakes are rubbing, the shifting seems not quite as smooth (Ultegra Di2) and the drivetrain seems louder. Is this normal?

As a note, when my bike was new, I played around a lot with the rear derailleur to quieten the drivetrain, to the point where it was actually not super smooth to go into the lowest gear (34-32) but this setup was more quiet. Over time it became easier to shift into that gear. Now with the new wheel (and new cassette and new chain) it is once again more difficult to shift into the lowest gear, however, unlike before it is quite noisy. So also considering the brake rub, it seems things aren't exactly in the same place as they were with the old wheelset.

I will have to try and play around with the setup again, but just wanted to know if this is 'normal'.

delbiker1 

IME, rarely can you change wheel sets without some adjustments to the derailleur. Disc brakes add another adjustment that may need to be done. Neither is hard. This can be true even if replacing with the same model of wheels. However, I am not familiar with Di2. My bikes need no more electronics.

ZHVelo

Thanks, yea I think the rear disc is now good, I had to twist the caliper in the right position. And sound seems to have at least to a large part come from me switching to wax and not having properly removed the excess. It is now at a point where I feel on the road I won't hear it anymore.

Front is more of an issue, it almost looks as if the pads have become misaligned because no way I twist the caliper can I see light on both sides. The pads just look too tight together now. I also ****ed up and leaked some brake fluid somehow so that will be more of a project now.

zacster

Here is something I harped on once in a thread. All of these components are supposed to meet a standard with some pretty tight tolerances. If you get everything within that tolerance it should just work, and that include swapping wheels. No adjustments should be necessary.

In your case either you've adjusted the bike out of that tolerance or the new component is out of tolerance. So yes, you need to adjust something to make it all work again. One thing to adjust, and someone else would've said it too, is your derailleur hanger. There is an assumption that it is straight and parallel to the plane of the wheel. It is possible that one of your previous adjustments was to compensate for a slightly bent hanger. Usually a bent der hanger is a source of noise. In any case you should be able to get it all to work quietly again. Oh, and with Di2, isn't the derailleur adjustment electronic? No more barrels to turn! I don't know much about disc brakes though, so probably you just need a caliper adjustment.

The big PITA these days is that there are so many competing standards. What works with one group doesn't work with the other. You just can't mix and match anymore. Hmmm, but maybe Di2 gets around that since you can adjust the pull ratio?

Polaris OBark

You probably need to re-seat the pistons, which is best done simply by pushing the pads apart with this tool (or something similar, like a broad, blunt cold chisel):



You can probably just do a top-off bleed if you need to replace some brake fluid from the f-up.

I wasn't clear if you want to go back and forth between wheelsets, but if so, you can get shims for brake rotors so they both occupy the same spatial position relative to the calipers, which saves you having to adjust anything. (I do this, but still sometimes have to push the pads apart a wee bit).

Iride01 

Where was the noise coming from? Chain rub on the front DR is more on my new bike with Ultegra Di2 than it was on my Paramount with Shimano 105 5800 11 speed. The chain stays are shorter on the Tarmac so the chain is more angled so it isn't easy to get it quiet from chain rub.

Changing wheels probably just put the cassette in a slightly different position and maybe more to the bad side. But if you run your Di2 in full syncro, then it'll never be in the Big Big combo that gives the most fits. And you'll have a better chance of getting the noise adjusted out if you are having rub in the small front/ big rear combo.

As for the brake, the body of the brake has slotted holes. So just loosen the bolts holding it to the frame and you can adjust it if needed. If you are going to be swapping wheels, then you might need to shim the rotor or hub to one side. Or start bending the rotor and have fun! However if it's just the pads and not the brake body that is in the way then push the pucks back in the cylinders and they'll figure out where they need to be after you actuate the brake lever a few times. After the wheel and rotor are in place of course.

cxwrench

To answer the OP's question, yes, it is normal to have to adjust.

squirtdad

it should vs is does is a big difference.

I am of the club that IME switching wheels requires some tweaking, index shifting every time and friction most of the time, but have gotten lucky once or twice.

the tweaking can often only a little bit....i.e twist or 2 of the barrel adjuster but I always check derailler hi/lo and then adjust derailler

Troul 

if you measure from the backside of the cassette to the outside edge of the NDS cap of the previous wheel, you should be able to install a spacer/shim(s) to achieve a close lateral spacing for the cogs. As mentioned already, you can shim out the disc to push it outboard if that is the tolerance you need to fill.

A little hi/lo is typically all that is needed if the wheel assembly is built right using decent parts.