Have had these on a road bike for 4 years with good usage, is there a good chance they are going pop soon?
No reason they should… the cables might go or something but the shifters themselves should hold up unless they get dinged and subsequently rust or something. Normal wear and tear doesn’t usually do too much to shifters…
Shifters do wear out and unlike Campy, ShimaNO shifters can’t be rebuilt and have to replaced once they’re gone. But if you should get a million or so shifts out of them before this happens.
?
I just had a set of 8 year old Ultegra shifters poop out on me. The front one is fine but the rear one is toasted. Up until this year it had been working great!
Time for something new!
Fleck
I’ll try again.
To paraphrase my LBS…
Campy owners tend to believe that their components are supremely durable, they run them until they are ragged and think they are rebuildable until I tell them what it’ll cost…
Shimano owners tend to shrug and replace.
They may not be able to be rebuilt, but I got a lot of life out of mine by disassembling them entirely each year, cleaning them, and lubing them, then putting them back together. New cables and housings every once and a while, when they start to get dirty.
I’ve had my current set (they’re DuraAce, but similar enough) since 98, and I got them used. And they still shift like butter.
Funny, I have some levers that claim to be 9 speed that are really 10 speed - cost me $40.00.
Another thing is that shifters wear - they do. You can feel how much crisper a new shifter is than an old one.
Not long enough.
I’ve been through 3 Ultegra 9 shifters on my road bike. I’ve got a third-hand DA9 lever on there now and the thing is rock solid.
Mine aren’t as old as 4 years, but they have done CONSIDERABLE mileage, including 2 accidents (not my fault, I promise). They look knackered, but it’s all superficial - like the plastic bit on the top the hood - you know, the bit that breaks off (or at least when you fall), is not there. The break levers have moulded to my fingers and the hoods have a very shiny appearance - YET they still work like they are new.
This is where tonight, they fail 
I have 8-speed Ultegra on my road bike, now entering its 10th season, each of which has averaged about 2,500 miles. The index pawls have definitely worn on the rear brifter–I have to push forward to engage them–but it works reasonably well as long as I flush it a couple of times per year with a solvent such as Liquid Wrench or WD40.
I should probably replace them, but I’m cheap.
David
My 8spd Ultegra STI on my road bike will be eleven years old next month.