SunRace CSM990 Wide Ratio Cassette 11-40T, 9 Speed, Silver, ST1457

I recently bought the sunrace 11-40t cassette to replace the 11-32t 9 speed on my bike to give me that extra cog to go up steep hills. The overall quality of the cassette looks pretty good. It did skip a little on my first ride with it installed. Will probably oil my chain a little better and wear it in a bit. The range is very good. It also has a 34 then 40 t. It seems pretty light as well. I am very happy with this cassette and recommend it for riders who need a little more low gears to tackle the hills.

For the money I knew this wasn’t going to be a Shimano XTR quality part, but I expected the cassette to actually shift given Sun Race is a large component maker and 9 speed technology has been in place for 20 years.This cassette suffers from 2 fatal flaws - a marginal design and crummy, low tolerance manufacturing.Design: The lowest 3 gears are riveted to an aluminum spider; next 4 gears and spacers are loose; last 2 gears have integrated spacers. If you’re counting, that’s a 10 part Jenga stack with no dowels or tabs to hold it all together as a unit (ie Shimano). This makes for a fussy install and results in play between gears due to issue #2.Manufacturing: The gears are stamped and have >0.025” tolerance even on a brand new freehub. May not sound like much, but this much play means you can move the gears back and forth AND in rotation even with the cassette firmly installed on the freehub with the splined nut. The play at the gear stack means there is no way to set up consistent shifting beyond the 3 lowest gears on the riveted spider. If you are OK using the lowest 3 gears only, this is your part. If you want to use all 9, buyer beware.This gets 2 stars - one because the 40T low gear is awesome if you don’t shift out of it, and one star because this has potential to work if it were made worth a damn.

I am 67, 6ft. 3 in. 230 lbs. I ride a 17 mile loop 2000 ft vertical. I would never make it without this 40 tooth gear. Works great and durable. I needed something strong not light weight. Just what I needed

My kids bike went from a 11x32 to an 11x40. He said it shifts as it should and he loves having 2 more climbing gears!