2 pcs 11T Aluminum Sealed Bearing Jockey Wheel Rear Derailleur Pulley for Shimano Sram Rear Derailleur Etc.

Fits Ultegra 10 speed. Nice smooth movement of the wheels. Looks good.Note that I ordered the black which is shown to have red centers but is entirely black. Would have liked the bling effect but mechanically does very well which should be most important.

The bearings are smooth and the quality is good. If you want to upgrade your stock pulleys with a pulley that has a much better bearing, and add a little color the process, these are a great, affordable option. In my case, I ride enough that every couple of years, I have to replace a derailleur pulley. It just happens after thousands of miles. I had originally started off with higher end, ultra-light pulleys, but learned over time they wear out all the same, if not faster. These are much more affordable then high-end and a perfect compromise of weight and durability. I would buy these time and time again, whether for my road bike, commuter or mountain bike, these are my go-to for either maintenance or an upgrade.

Put these on a shimano slx. They fit perfectly and look good.

Update:The seller contacted me and said they had revised the jockey wheels, and wanted to send me a new set that would work. I said "sounds good", and they arrived last week. I installed them and took my first ride yesterday. They worked great. Nice looking, quiet and no chain suck. The bearings seem to come dry (dryish?) so make sure you get some lube in there before you install them. Otherwise, I'm very happy and good job on the sellers part to reach out and make it right. Rating revised to 4 stars.--------------------Update:I found another review here, with a video, and the guy had the same problem as me. These are NOT compatible with narrow chains on high count cassettes (in my case a 9x). The seller should make this clear. Down to one star.--------------------I bought these about a year ago and finally just installed them. They look great and the quality seems good, but they're grabbing the chain as it goes by, so I put my old ones back on. I just rebuilt the drivetrain, so the chain is brand new. Maybe they'd wear into the chain if I gave them a short ride, but I don't want to risk damaging the new chain doing that. There are a lot of good reviews here, so I'm unsure why I'm having a problem. I have a Shimano 3x9 gearing mountain bike. Maybe with narrower chains (for use in 9 wide cassettes), this part is too wide and jams into the chain. Anyhow, beware.

I've been writing a nice $500 giant mountain bike that I've owned for seven or eight years. Lately, I had noticed that the rear derailleur wasn't shifting like it should. First, I tried simply cleaning and lubricating the chain and gears. When that didn't work, I went ahead and installed a new chain (The old one was pretty gunked and caped up with dirt and grime). That improved the shifting, but it still wasn't quite right.I noticed the plastic gears included with the factory detailer we're looking a little worn, and I decided to give these new gears a try. The installation only took a couple minutes, and sure enough - My bike shifts great now! Occasionally I'll have the gear that will lag for half a second or so before shifting. The only thing left to change out is the shifter cables, but I can say that these new gears made a definite difference!

Arrived as advertised...

I tried and adjusted my rear Derailleur to make use of the pulleys - but it's just not working. I am not sure exactly what's the problem (my suspicion is that the pulleys are not the right thickness and the pulley teeth are too large) no matter how much I tried adjusting my Derailleur it would still be misaligned and the chain would be slipping on the cassette.I ended up returning the set.

I cycle. A lot. 3-5k cycle commute per year, rain/shine/heat/cold. I have always looked 'askance' at such blingy gizmos as these alloy pulleys. But reading reviews, and with my old plastic pulleys being rather worn, I decided to give 'em a whirl. They fit perfect, look cool, are dead silent, and IMPROVE SHIFTING. This was unexpected. They hold the chain more precisely than the OE plastic wheels ever did, and make shifting noticeably sharper. This is old high-end Sram X0 10-spd drivetrain and it's never been better. I've run 'em close to a thousand miles and the difference still surprises me. Recommended. If/when the get worn I'll get another pair.