Shimano 7900 reliability??

[BlackTiBob]

Hi,
how is the Shimano 7900 reliability?
I'm just about to order the groupset and a buddy says his friend (head mechanic at big bike shop) reports all kinds of problems with shifters/ result of hidden cables/ problems with them. His friend says 7900 now least reliable of Shim, Campy, SRAM.

I tend to really doubt this.
Anybody know anything about this-- true or B.S. ??
Thanks

[Adam]

Bs

[oldpotatoe]

Hi,
how is the Shimano 7900 reliability?
I'm just about to order the groupset and a buddy says his friend (head mechanic at big bike shop) reports all kinds of problems with shifters/ result of hidden cables/ problems with them. His friend says 7900 now least reliable of Shim, Campy, SRAM.

I tend to really doubt this.
Anybody know anything about this-- true or B.S. ??
Thanks

There is a different 'feel' to 7900, due to it's under the bartape housing and the RH shifter is limited to 2 cogs max per sweep to a lower gear vs 3 on 7800, etc. BUT no reliability issues. IME, sram is the least reliable by far.

Search cyclingnews.com for a test of 7900.

[nahtnoj]

I've read anecdotal evidence of the same - 7900 is a pain to set up, cables under the tape combined with a weak RD spring make for really vague shifting. In some cases replacement with a 7800 RD has solved the issue.

Why would you doubt the report of the head mechanic at a major shop?

[Adam]

FWIW, we have not encountered any of these issues at our place...we have however done a lot of warranty work with SRAM. To SRAM's credit, everything was taken care of easily and customers satisfied. Our wrenches far prefer setting up Shimano groups over the other two. This from a Campy guy currently.

[dekindy]

I do not have the groupo but your post caused me to look around for user feedback. The best review I read said that the key is to run the cables behind the bar to get as shallow a bend as possible. Once adjusted it should only get out of adjustment once after cable wear and then you should be good to go.

[avalonracing]

Why would you doubt the report of the head mechanic at a major shop?


Because it is just an opinion. It never fails to amaze me when I hear things from specialists and professionals like the IT guy at my office who says "Mac Suck" or the bike mechanic (who wasn't a racer) that said "A Serotta Legend Ti is a cruisin' and chillin' bike but not a racing bike".

[BlackTiBob]

The head mechanic is one opinion but it did cause me to pause and wonder as I do not want reliability problems.

That opinion is "balanced" by a shop owner I met on a trip who saved my skin with a Mavic Ksyrium SSC spoke. He said he was a lifetime Campy guy but he'd buy 7900 over Campy 11 speed.
So, the opinions are varied.

I'm just trying to sort if 7900 is reliability/faulty design of shifter (as the mechanic thought) or vague shifting unless you take care to have no sharp bends in the cables (that sounds more likely).
thanks for you opinions.
More are welcome too.

MN report--6" new snow with up to 20" expected by Sat AM, yuck!!!!!

[oldpotatoe]

The head mechanic is one opinion but it did cause me to pause and wonder as I do not want reliability problems.

That opinion is "balanced" by a shop owner I met on a trip who saved my skin with a Mavic Ksyrium SSC spoke. He said he was a lifetime Campy guy but he'd buy 7900 over Campy 11 speed.
So, the opinions are varied.

I'm just trying to sort if 7900 is reliability/faulty design of shifter (as the mechanic thought) or vague shifting unless you take care to have no sharp bends in the cables (that sounds more likely).
thanks for you opinions.
More are welcome too.

MN report--6" new snow with up to 20" expected by Sat AM, yuck!!!!!

As a shop owner I think Campagnolo still has the most comfy levers, the most functional and the prettiest(NOT trying to make this a gruppo taste thread). By far the simplest lever innards as well.

With SR and 7900 about the same price, choosing SR is easy.

If set up right, 7900 has the best front derailleur action of the bunch and in spite of plastic bits on the brakes, probably the best brakes also.

[torquer]

I suppose its just as well that the bike industry isn't required to perform large-scale, double-blind, clinical trials (like the drug industry, say) before releasing new products. That's what racing (and early-adoptors ;) ) are for.

So all we really have is anecdotal evidence. Problem is, a few "head mechanics'" negative opinions get picked up on the web, and soon become conventional wisdom, while most users don't have any problems, but don't feel the need to chime in, either.

I'm not defending the 7900 group per se here (I'm still fine with my 7700 bikes, knock on wood), but historically, the big S has not been known to let retail customers become their beta-testers.

But we'll see if a 7901 groupset is released. In the meanwhile, I sort of recall someone across the hall had a work-around installing thinner cables for improved shifting.

[cdimattio]

Hi,
how is the Shimano 7900 reliability?
I'm just about to order the groupset and a buddy says his friend (head mechanic at big bike shop) reports all kinds of problems with shifters/ result of hidden cables/ problems with them. His friend says 7900 now least reliable of Shim, Campy, SRAM.

I tend to really doubt this.
Anybody know anything about this-- true or B.S. ??
Thanks

I am a single data point, but am running Shimano 7900, SRAM Red, and Campagnolo Record on different bikes. I find the Campagnolo to be the most reliable, followed by the 7900 and lastly the SRAM Red. I would have rated Shmano 7800 the equal of Campagnolo.

I think there was a decrease in rear shifting performance from Shimano 7800 to 7900 due to the hidden cables. Front shifting is improved with 7900 despite the cable routing. Reading the reviews I had expected an improvement in braking performance from 7800 to 7900, but found it to be relatively modest.

[jpw]

Seems fine to me, although I'm using bar end shifters with nice sweeping curved cable routing :-)

[dave thompson]

I switched from 7800 to 6700 (Ultegra level 7900 stuff, see my comparison here: http://forums.thepaceline.net/showthread.php?t=63990&highlight=rode+report ) and did all the install work myself. There was a bit of a learning curve because of the vast difference between the old and new but otherwise was straightforward.

I hear tales, more often second-hand, of reliability and function issues but in my case, everything works perfectly, smoothly and I've had zero issues. My rear shifting is very good, smooth and positive with no vagueness at all. Over 700 miles since the initial installation and it's all running smoothly. The only change I'm making over the winter is a bar and stem change, which is for fit purposes only.

[caleb]

MN report

If you're in MSP, I can only think of three shops (Grand Performance, Flanders, and Excel) that have set up more than a couple 7900 groups. If the shop is on that list, I'd listen to what they have to say. If it's not, you may want to consider the sample size.

[mike p]

I don't have a 7900 group myself yet but have plenty of buddys that do and have heard no complaints.

Mike

[11.4]

I've been riding two 7900 groups, one on a summer bike and one on a winter rain bike. I used standard Shimano cables and housings, everything absolutely stock including original chain (though I've now gone to the KMC gold chains as replacements). Both sets have about 4,000 miles on them.

Absolutely no breakages, including on the rain bike where everything else (rims, tires, saddle, etc. all show a lot of wear. I do find I go through the 7900 brake blocks a good bit faster, but the braking is also significantly better than on the 7800s and better than either Red or Super Record. Cables have needed no maintenance or care, and I've never had a shifting or braking problem.

I will say that the 7900 finish doesn't age as fast as the 7800 did. There were reportedly some early 7900 cranksets that had corrosion problems, but the ones I have don't show any tooth wear, any surface cosmetic problems, nada. I've dropped the chain off the big chainring on the rain bike a few times and there are no marks on the big ring or arms.

I had one glitch with the 7900 STIs, but a minor one. On the rain bike I came home one day with a little bit of jamming on the gear changes. The innards of the lever are rather more exposed compared to 7800 and a squirt of TriFlow released a hunk of organic road debris. After that, all was fine. I'm not sure how I'd feel about these levers in cross, but otherwise they have been completely durable. And despite carbon everywhere, the carbon doesn't show any noticeable wear (including levers from leaning against walls and the like) -- the finish is designed for high durability.

Almost all the miles on both bikes are on one 7900 cassette and it doesn't show anywhere near as much wear as the same size 7800 cassette showed after the same mileage.

I'd second the point made above that not too many shops have actually installed all that many 7900 groups, and with the market increasingly divied up among different groups, even OEM 7900 groups are probably a bit scarcer. And I would always be skeptical of problems reported by someone with a bike and OEM 7900. Elitist, I know, but a lot of those buyers don't really know their equipment or how to use it.

Mine is only one data point but in riding with my team and others, I don't see that much 7900 yet but certainly don't see or hear of problems. I have three local shops that see a lot of me, and they are all high on it. I'd venture that with so many different groups available, there's just a bit more polarization in opinions about any of them. I've also heard more criticism of Super Record, of Red, and so on. I doubt anyone has a higher noise level than any other -- people just either love or trash what they have, and you hear about it and any other group in that light.

[AFS]

I have a mix of new and old components. The 7900 shifters have given me no problems. There's about 5000 miles on the shifters, no rain or dirt rides. I do run the front derailleur cable a little looser than previous shimano setups. The biggest thing for me was that the reach increased with the 7900 shifters and I had to go with a 1cm shorter stem.

[SPOKE]

I've don a couple installs with both the 7900 and 6700 groups.
Just have to make sure all cable housing ends are deburred and that you
spend extra time making sure all the cables and housing are "seated" well in the brifters and frame stops. If you do this you shouldn't have any issues except minor cable tension adjustment after a couple rides.
You will still have to replace the rear dérailleur inner wire every couple thousand miles because it will break at the transition between the brifter and cable housing.

[Pete Serotta]

as SPOKES says... I have about 1K miles on 7900 and no problems. It took some getting use to for me at least. This is especially in regard to upshifting on the front chain rings.

I have heard of no problems to speak of - except cables are real sensitive.