Show your teeth.
If you've put in the big miles on your Shimano Ultegra 6800 11-speed cranks, these chainrings are factory replacements that bolt right onto their distinctive 4-arm spider. The outer rings feature lightweight Hollowglide carbon / alloy construction with ramps and pins to match up with the aluminum inner chainrings.
Shimano recommended pairing:
B-Stock - This product has one or more B-Stock units available. These units can be purchased at a discount (see option select). B-Stock units were returned from other customers and may have missing or damaged packaging materials. These units are otherwise as new. The full manufacturer warranty applies. Click Here for more information.
6800 - 34T
Mfg PartNum: Y1P434000
Mfg PartNum: Y1P436000
6800 - 39T
Mfg PartNum: Y1P439000
6800 - 46T
Mfg PartNum: Y1P498050
6800 - 50T
Mfg PartNum: Y1P498060
Mfg PartNum: Y1P498070
6800 - 53T
Mfg PartNum: Y1P498080
one might think and expect that the 46 tooth ring would be a direct, physical replacement for the stock "outer" on an fc 6800 crankset.....surprisingly it is not.....an extra kit is required to attach it, bringing the total cost for the single 46 tooth ring to more than $xxx....even worse is that the extra kit looks odd because it alters the smooth lines of this otherwise wonderful crankset............the inner ring sizes are reasonably priced so i kept those......free shipping is a nice touch......beware the 46t......it shouldn't be listed with this product without a few emphatic caveats or asterisks
I bought a 39T ring to replace the stock little ring on my 52T/36T crankset. I live in an area with lots rolling terrain, and the 39T ring helps me hit the gearing sweetspot without inefficient crosschaining. I run a 11T-28T cassette and never feel undergeared on hills. Shimano says the 39T is only for use with the 53T ring, but mine works fine with the 52T; I've ridden this setup almost daily for ~2 months and only dropped a chain once due to bad shifting/pedaling technique.
After 11,000 miles and a couple of chain replacements another chain was due, wearing to .75%. That was more than my original front chain rings could bear and I was slipping on my large ring after the new chain was installed. I replaced my rings with these and no more slipping. In fact, what surprised me was the decrease in noise. It was remarkable. These are not cheap but they're genuine, in stock, and shipped right away. It was well worth it.
My bike had a compact set, which was just a little too low for my fast bike. I like spinning fast on my inner ring, but with a 34 tooth Id have to almost cross chain to go my normal speed. I bought a 36, and it is perfect. Now I can keep it more in the middle of my cassette and spin away. Good quality, worked perfectly swapping the 34 to the 36, with a 50 outer.
Came stock on the bike so just a maintenance purchase but really it's Shimano Ultegra, works fantastic with Di2. Original parts lasted a long time so no disappointments there. Smooth quiet and reliable.