Black/Sliver Rear Derailleur RD-TY21B 6/7 Speed Direct Mount/Hanger Mount for Mountain Bike Kids Commuter Bike

Nice Derailleur. Works well on my mountain bike. I had installed a different rear sprocket pack that had very low ratio for first gear (Large diameter) and needed a derailleur that would take up the extra slack. This worked very well.

direct replacement

Good quality for the price barrel adjuster a little stiff and hard to turn but functional cable pincher nut came unattached other wise works great

Exactly what i needed

I got this for a trek mountain bike with 7 speeds on the rear and trigger shifters. Overall, this derailleur worked great. The install wasn't complex. Just a matter of getting it fine tuned just right to pull the correct gears. Took me a while to get it right, but after that I was having no issues with shifting. Unfortunately rear shaft on the bike broke which also broke the frame on the bike. So I'll just use this on my next mountain bike . But its a great value for the money and I wasn't having any issues with its operation once installed.

I have 6 gear wheels on my old Mercier frame. My old derailleur broke. I recognized the Shimano name so I bought one. I had to break the chain to install it. At first it looked good but its shifting range is severely limited even after adjusting the High and Low stop settings. I can shift to 1-4, and the derailleur can go farther towards the high gears (small diameter) end but it does not pull the chain over enough to engage 5 (and thus also 6). I wrote to ask for help in case I did something wrong. The vendor simply gave me a refund without engaging the issues. So I guess it's just the product. I think the hanger may be too long, the guide wheels seem farther away when mounted than my previous derailleurs. That might explain why the chain cannot be pulled over enough to get to high gears.

I found the frame on the street. I guess someone dumped it there. I checked out the frame and figured it was very nice so I decided to turn it into a new rideable bicycle. I need it this part right away. I ordered it and it showed up this time quickly. It is what I expected from Shimano now all I got to do is assemble the bike at this part and get it up and running. It's going to be a nice used bike. Most Shimano bike parts are pretty damn good and this one is no exception it looks good I don't like the plastic Wheels. but that can be changed

I used this to replace the rear derailleur on my son’s bike that had taken the abuse of a now 10 year old boy over a couple of years. This derailleur installed perfectly as a replacement (I did compare to make sure I was getting the right one), and had an excellent level of adjustment for the low gear and high gear stops, as well as the indexing to align each gear. The final installation works perfectly and I expect this one to endure for the life of this bike (which with a 10 year old boy may only be another year, but that’s not the derailleurs fault!).