I recently wore out my old GX Eagle cassette and replaced it with a brand new one, only to find this new cassette has the same problem as my old cassette did when new: An annoying clicking noise in one gear! It was time to investigate. Note that this fix may not apply to all cassettes so only attempt at your own risk!
The noise is ultimately caused by the outer link of the chain making contact with one or two teeth on the next smallest gear. The teeth are shaped so that 2 teeth on each gear sit a tad closer to the adjacent gear, and even with a perfectly aligned and adjusted dertailleur, the chain may run so close to the other gear that these 2 teeth contact the outer links and cause the somewhat annoying and even concerning clicking noise, which can't be silenced by adjusting the derailleur and still retain proper shifting.
The fix is to grind a little bit off the inside of the tooth or teeth that contact the outer links of the chain. These are easy to identify by slowly rotating the cranks with the bike in the gear that makes the noise, and paying careful attention to the teeth and chain. As the tooth engages the chain, and starts to wrap it around the cassette, the "offending" tooth on the adjacent gear will just touch the outer link and cause the noise.
The noise is ultimately caused by the outer link of the chain making contact with one or two teeth on the next smallest gear. The teeth are shaped so that 2 teeth on each gear sit a tad closer to the adjacent gear, and even with a perfectly aligned and adjusted dertailleur, the chain may run so close to the other gear that these 2 teeth contact the outer links and cause the somewhat annoying and even concerning clicking noise, which can't be silenced by adjusting the derailleur and still retain proper shifting.
The fix is to grind a little bit off the inside of the tooth or teeth that contact the outer links of the chain. These are easy to identify by slowly rotating the cranks with the bike in the gear that makes the noise, and paying careful attention to the teeth and chain. As the tooth engages the chain, and starts to wrap it around the cassette, the "offending" tooth on the adjacent gear will just touch the outer link and cause the noise.
Great tip, fixed me right up. I used a thin little file instead of the grinder.
ReplyDeleteI thought for sure I had reached the end of my GX cassette’s life, as this issue didn’t pop up for me until almost 1000 miles on the cassette. Carefully filed the teeth between 4th and 5th cogs and it’s running smooth and quiet again with a new X01 chain! This and the SB150 shim article have been so helpful, thank you!
ReplyDeleteGlad to have helped!
DeleteThis noise can also be caused by a single slightly bent tooth (personal experience). The chain will ride up on this bend, and eventually 'pop' into place. Quite maddening. It is critical to put the bike on a stand and get a visual as to what's happening.
DeleteThis is unacceptable, Sram has to improve the quality, quality control, but great hack. I've not tried any new Sram stuff, only had a Sram cassette come on a bike when I was a kid. But with SunRace cassettes I had issues with the teeth and cogs bending, twisting, and sharp edges at the ramps and teeth, so had to use sand paper to carefully make those areas smooth, and a flat head screwdriver to bend the cogs and teeth back, butt it kept happening. It was 11-46T ( ridden on 2014 Trek Fuel EX 29er, a flexy and drivetrain abusing bike) and the 11-50T, but on the 11-50T ( used on Geometron G1, later on 2010 Trek 6300) the biggest cog developed a lot of play, and eventually it was so bad the shifting point changed during each shift. I later tried M5100 cassette, But only for a few rides, but it performed well, even when intentionally shifting bad, it shifts were smooth, and made little noise, but the Garbaruk 11-50T arrived so I installed it, but the Sunrace 11-50T Shifted badly, I had Box One X-wide on the Trek 6300 but the hsiftign point was bad, the RD had worn out bushigns after almost 70km, but that was not the only reason for bad shifting, the mentioned shifting point issue due to the play was the cause, I installed a M6100SGS shifting was horrible with the sunrace cassette, but when I installed the M5100 the shifting was smooth. I need to get rid of that bike, and build something else, but so far I kept it as a spare, but a horrible bike to ride. but the G1 is amazing.
ReplyDelete