So here's the issue. I just put on a brand new shimano xt 10 speed chain to replace my scratched out old 10 speed shimano xt 10 speed chain. The new chain is sized to the correct length. So here's my issue. The new chain 'jumps' on the first two (small) cogs of the cassette. The issue only happens when I'm on the bike, and I can't get it happen when I have my bike mounted to my work stand. What the hell is going on? I'm at a total loss.
You waited too long to replace the chain. The cassette wears right along with the chain. A new cassette is required.
I've already changed out the cassette. did it at the same time. Old chain works perfect on the new cassette, new chain nope.
Is the chain going the correct direction? Those chains are directional. If you are using a KMC Missing Link, those are directional as well.
Check the chainring also, I had what I thought was a skipping cassette, turned out to be a worn/skipping chainring. It was happening most often on the smaller cassette gears also.
So everything the same, new chain skips, you put the old one back on and it doesn't? Stiff links would be first guess. Second, a worn chain has a bit more lateral play so could adjust for a slight out of adjustment derailleur or even a slightly bent hanger/derailleur. Seems odd tho.
Did you actually see the skipping on the cassette while riding? If not +1 for the chainring. Apply pedal force to the cranks while stationary with the brake on. You may see the chain physically start to come off the chainring. Best to change it all at once.
Having same problem. Just replaced my chain and it skips on the two smallest cog in the rear. I know it's not the chainring in the front. Hanger looks straight. I always keep a close eye on my chain stretch.
I would advise you to clean and relube the freehub to rule that out. It is possible that the pawls are dirty and they slip when you grind the high gears.
Did you install the cassete correctly, spacers and all? is it tightened down? Check that out and if that doesnt do the trick, check the chain rings. If its not the chain rings, try a new chain, maybe you have some stiff links. If thats not the case check derailur if its adjusted correctly
Maybe try adjusting the rear derailleur adjustment on your right shifter. If that doesn't work add a link to the chain and check the rear cassette for play.
I had the same issue on the smallest cog of my 9 speed cassette. I was putting together a cheapo build for my wife using the cheapest new 9 speed cassette (Sunrace) I could find as well as the cheapest 9 speed chain (KMC). It would skip on the smallest cog when applying a decent amount of torque. I tried putting on an old 9 speed SRAM chain with well over 1000 miles on it... stretched like a mofo, and it worked fine. (-_-!) Since your old chain works fine, I'm gonna guess the new chain is the issue.
I've had the same issue many times, always a worn out cassette, replace the cassette and it should work fine, count the links on your old chain and makes sure your new chain has the same amount of links, the old chain will be stretched and might appear a little longer, that's OK. the teeth of your cassette have worn with your old chain and are not rampped up enough to work properly with your new chain, time to replace. You should change your chain more often if your wearing out your cassettes, its cheaper in the long run that way.
Not that it couldnt happen, but I seldom see the smallest cogs to be worn before the middle or largest cogs. People tend to push a chain ring that keeps them in the largest 2/3 of the bunch.
I had a similar problem and solved it by having the derailleur aligned. It looked "straight", but only a small variance caused problems with the smallest gears.
Yeah, that's what I'm doing today. I've tired everything. Plus when I drop it off I can drool all over the new bikes Sent from my iPad using Tapatalk HD
