Is this potential Di2 upgrade going to work?
 

Hi

I have a bike with mechanical Ultegra 8000 with disc brakes. It has all internal routing.

I also have a spare 8150 rim brake groupset from my warrantied Madone

I’m thinking I could upgrade this bike by buying two 8170 STI levers and putting the rest of the 8150 stuff on there - battery, cables, derailleurs.

Should I be able to leave the existing calipers in place? Or would 8100 calipers be better (servo wave?) - I don’t know how much spare hose there is to re-cut but if I could leave that routed it seems a slightly easier job.

IIRC The 8150 brakes also retract the pads a little more after releasing the brakes as compared with 8000 brakes.
Not a huge selling point, but is the difference in the caliper or lever ?

Barry

The 8000 series calipers will work with 8170 STI levers. Servo wave is in the levers so that will work too. FWIW 8100 series calipers retract the pistons slightly more than 8000 series calipers, so you will have less hassle with brake pad rub with them. 8100 series calipers are also easier to bleed.

That’s really useful, thank you!