Dura-Ace R9170 vs Ultegra R8070 hydraulic Di2 groupsets

johnmcl7

I have a 2017 Trek Domane SL5 Disc (https://archive.trekbikes.com/kr/en/2017/Trek/domane_sl_5_disc#/kr/en/2017/Trek/domane_sl_5_disc/details) with the RS505 hydraulic levers which I've been toying with upgrading to Di2 but never seen a good price on the R8070 groupset.

I noticed Merlincycles have ten percent off the Dura-ace R9170 groupset which means it's £350 more compared to Ultegra however I'm finding it difficult to identify what exact differences there are, I've seen the general comments about Ultegra vs Dura-Ace and individual reviews but not much comparing them. I've seen some claims that the two are identical aside from the levers on the Dura Ace being carbon therefore you're just getting a slight decrease in weight for the money but would appreciate any thoughts on this.

Also is there anything else I need to change my current levers over? I'm planning on going for the bar end junction box for convenience but wondering if I need any adapters for the brake hoses or can I use my existing ones?

pippi_langsamer-2

Functionality wise, very little difference I'd imagine. It's almost entirely down to weight as you say- carbon and Ti bits of hardware as opposed to plastic, alu and s/s.

That all said, for the sake of £350......I think I'd go for DA just because.....

(No experience of 9170 or 8070. Still loving 9070 series...)

I've got the bar end jobbie in my bike too. To be honest, it's not that great. I prefer the standard stem mount tbh. When you do need it, the program button in the bar end is VERY difficult to locate/ operate- especially if you're trying to make adjustments on the move.

The wireless Bluetooth in-line unit is handy however.