Performance of Dura Ace 9000 group with 7800 cables

[martinko]

Hi all,
I looked everywhere but didn't find results of using Dura Ace 9000 with cable set (both brakes and shifting) from older 7800 groupset. I've got one new set of 7800 lying around and I can get used 9000 for very nice price. Although I am not sure how it will perform.

I think it would work but the question is how. Wouldn't it be problem to bend 7800 cables under bartape?

The 7800 set comes with different mix of ferrules, but these can be supplied cheaply. I wonder about the housings and cables.


Thanks

[baldkingpin]

7800/7900 cables/housing work perfectly with a 9000 groupset. In fact (and, hopefully, this doesn't incite anyone too much), I use them instead of the dumb polymer-coated 9000 cables, which work great at first but tend to fray and gum up over time. I've got probably 20k miles on 9000 cables and way more on 7800 cables (10k/yr x 8 yrs?) and don't think the 9000's work any better. A solution to a problem that never existed IMHO.

Maybe Simsno developed the polymer cables because 7900 was so problematic (in many areas...) in that cable resistance was a real issue. However, 9000 is so incredibly smooth iit's simply not necessary.

'Course, di2 is the ultimate solution. Switched a year ago, best bike acquisition I ever made:)

[skinnywellfed]

(10k/yr x 8 yrs?)

What are you saying? Are you saying you have been running 7800 cables on a D-Ace 9000 equipped bike for (8)yrs? I clearly don't understand something. D-Ace 9000 came out in 2013.

[baldkingpin]

Ah, perhaps a bit inartfully phrased on my part. I'll try to be more clear.

I've used many 7800 cables on many 7800 groupsets for maybe 8 years, averaging over 10k per year. So, lots of experience with 7800 cables in their intended groupset. Always worked great. 7800 stuff still rocks, I kept a bike with it. I don't miss exposed cables/housing but the runs were so perfect, shifting was silky smooth. We had to suffer through 7900, but it all worked out in the end with 9000. I digress.

I got 9000 right when it came out a few years back. Had 9000 groups on two bikes and ran 9000 coated cables for quite a while on both bikes. Again, lots of miles with 9000 cables in their intended groupset. Frayed, gummed up a bit in their housings, but always worked very well even when it started looking a bit janky.

Over the past 18 months(?) or so, I've run standard non-coated Shimano cables in my 9000 systems. Don't know how many miles - hard to say since I got a di2 setup on a new team ride and switch bikes a lot - but a significant amount (5-10k?). This also worked perfectly.

Hope this is clearer. Not bragging about experience or miles (I'm an aging Cat. 2 in California, we're a dime a dozen), but I've ridden regular Shimano cables with both 7800 and 9000 gruppos extensively and done significant training/race miles on 9000 polymer cables on 9000 stuff. My experience has been that I actually prefer the non-polymer cables. And I'm not alone. Search WW or the web for fraying and clogging and you'll see similar feedback. The 9000 cables still work very well after they start coming apart, it's just that I don't think they add anything or work any better than regular ol' cables.

I'm not a luddite, like the latest/greatest as much as the next weenie, but the 9000 cables weren't an improvement over non-coated cables IMHO. Not making any statements about non-standard systems (P-Cordz, Ashima, etc.), just answering the OP's question about running standard Shimano cables on 9000. Answer: it definitely works well.

[skinnywellfed]

Got it. I have also been on 7800 groups and cables for a very long time. When the 7900 group came out I just took a step back and watched everyone else. Never bought any of it, the 6700 or the 7900. I just sold off all my older gear. Crazy how people will kill to get their hands on some of the remaining 7800 kit in good shape. I understand their zeal, the stuff shifts like melted butter.

So I recently bought a mixed bag of 6800 shifters, brakes, cassette and then 9000 derailleurs and chain. And I began doing a bit of research, reading numerous threads where people have complained at length about the new poly coated cables. And occasionally I would see reports of people running the older 7800 stainless cables. Reports were positive.

It all makes sense. 9000 / 6800 / 9001 / 5800 have achieved so many gains that aren't associated with the super slick poly cables. I have had my hands on 7900 and 9000 shifters and could see first hand how the mechanics were re-designed. And then you have the long arm of the f. derailleur. And then the re-worked parallelogram of the r. derailleur. So even if you take the poly cables out of the system it is understandable that the latest generation can deliver good results.

I'll let my new 6800 cables play them selves out and then I doubt I will seek out any more poly cables as replacements.

[dunbar42]

I've switched back and forth between PTFE and polymer coated cables on 105 and I notice a pretty big difference in shift quality on the RD. I would say the polymer cables require about half as much force to downshift the RD. Plus, they aren't as finicky when it comes to fine tuning the rear derailleur. Yes, they do fray but I think the benefit in shift quality is worth the hassle of replacing them more often.

[skinnywellfed]

dunbar, aren't you using the new poly coated cables with a 5700 group? What exactly is your set up? Shifters, derailleurs, cables etc.

[dunbar42]

I was using full 5700 before and now have upgraded to 5800 on both of my bikes.

[5DII]

anyone have info on 7800 vs PTFE cables?

[skinnywellfed]

I recently purchased some new 6800 shifters. Before the purchase I read 8 ~ 10 diff. threads on W.W. and over at RBR Forums about the Shimano 9000 & 6800 poly coated cables.

People reported very good results with Yokozuna, with the D- Ace 7900 PTFE cables and with non-coated Shimano stainless cables (that would be the 7800 cables).