Mountain Bike Reviews Forum banner
1 - 7 of 7 Posts

·
Registered
Joined
·
43 Posts
Discussion Starter · #1 ·
I have about 3800 km on my X01 Eagle cassette from 2018. Everything has worked great, except for a small chain slip when going to 42T either from the lower or higher gear. I think the chain gets on top of the teeth and then makes a «ka-bunk» sound as it falls into place.

But recently a new problem appeared. I changed from 36T to 38T (I do gravel racing) up front and it was working as normal (including the «gearing to the 42T «ka-bonk- sound). Then I replaced the X01 chain (it had about 0,6 stretch) with a new X01 chain of the same length (4 links overlap + powerlock for a hardtail according to SRAM manual).

Now it keeps slipping when in 50T when climbing steep hills (power meter says 240+ watts or so). It's the same «ka-bonk» sound as on the 42T, but 2 of the slips come just after one another in time. So 2 slips come after one another, then 1 crank revolution, then 2 slips after one another.

Powerlock has the correct direction, limit screws are correct and B screw adjusted with red SRAM tool (and fine tuned in and out in small increments), but the slips are still there in 50T when hill climbing.

I thought maybe the cassette is worn, but it looks good. Besides, normally the smallest cogs are the first ones to
cause slips.

What do you think, is this the «chain running on top of the teeth» problem or simply a worn cassette? These slips in 50T do not occur with the old chain that has 0,6% elongation. I have a video in 60 fps of the 50T chain slip if that is helpful.

cheers!

Tire Bicycle Crankset Automotive tire Wheel
 

·
Destroyer of Worlds
Joined
·
462 Posts
I had a sorta similar problem with my Specialized Enduro. Every gear worked fine except 2, which kept clunking and trying to shift to third. Playing with the limit screws didn't do anything, but adjusting the shifter cable tension fixed the problem. I think in my case, the index position was just wrong enough for the chain to want to climb out of the gear. A half turn or so and it stopped, and none of the other gears seem to be affected.
 

·
Registered
Joined
·
1,595 Posts
excess cassette wear = new chain slip.

had it happen to me after running a chain too long. slipped on the new chain only and only in the gear most worn/used by me.

a chain could maybe ghost shift if its got a new edge that catches on a shift ramp.

to fix, check your derailleur hanger alignment, then view the chain in 8th gear and make sure the plates ceter between the next harder and next easier gear. you might hear the odd tick w less than perfectly set shift tension.
 
1 - 7 of 7 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top