How To Fix Bike Chain Skipping/Slipping/Jumping Gears

heythere's I've done a few bit videos recently having to do with adjusting derailers and shifting issues and stuff like that and I've gotten a few questions on what causes chains to slip skip jump and how to fix those so I'm gonna kind of go over the causes of that and how to fix it now one of the most common causes is simple derailleur adjustment on modern derailers with index shifting the pulleys in the cage here should line up with the cog that the chain is on and what happens is if the adjustment is slightly off to where the pulleys are slightly off of not in the line with the the cog there maybe it's seen in between two cogs that the chain especially under torque might try to jump to the next cog and then maybe back again and so you simply need to adjust the derailleur a some videos that where they where at just the trailers but basically you're going to adjust the barrel adjuster here and adjust it so that the pulleys come over and line up with the COG that the chain is on and that will often solve the problem now if you have older bike with friction shifters then you simply need to be adjusting the shifter so that the trailer is then lined up with the Col you'll have to kind of do that manually by feel and practice now another thing to look at that will cause the chain to kind of jump around a little bit is a Ben trailer or derailleur hanger the cage here should be in a straight line with the cogs but if you find it it's kind of bent over in towards the spokes or bent out away from the spokes or kind of at an angle then it could be that the derailleur itself is damaged or more likely probably the hanger is just a slightly bent and I have a video on how to strain their derailleur hanger if you check the description of this video you can see that and so often just straightening that out that might fix the problem - okay the issues I've discussed so far gentlemen cause what's called Auto shifting or phantom shifting where the chain will try to slip over another cog and back when you don't really want it to now another issue is slipping to where the chain will actually slip over the teeth and then fall back into the next slots over and what that's awesome often caused by is a worn chain and/or a worn cassette / freewheel now a worn chain is very easy to check you can buy a gauge like this for that and you just kind of set this in there and bring it down and this little part over here shouldn't fall down into the little gap between the teeth if it slides in then that means the chain is worn I also have a video on how to measure a chain we're using a 12 inch ruler so I'll include in the description a link to that video as well so but checking the chain is very easy so if the chain is worn go ahead and replace it with a brand new chain either way we want to go back and check out the the cassette especially if the chain is worn okay so now identifying a worn cassette or freewheels a little trickier and a lot of times this takes a little bit of experience that you know what you're looking at one thing to keep in mind is people tend to write in some cogs more often than others so those cogs are going to wear faster than the other cogs that are not written in as much and also the smaller cogs tend to wear faster than the big cogs under the same writing amount because the chain is in contact with fewer teeth on the smaller cogs than they are on the bigger ones and so each of the teeth is just going to wear a little bit faster than the others but we're going to look at is look at the at the cogs and look for misshapen teeth so just look at the teeth and you might find like 1 2 3 the cogs that the teeth are worn differently than the teeth on say the largest cogs there that they're just going to be the teeth it'll be like they're going to have weird ramps there so that's one thing to look at they also make some tools this one here is called Camp C sprocket checker and the problem of the tools is they don't work equally well on all different cassettes and free wheels so you have to kind of take them with a grain of salt but you kind of drape these over here like this and this is like a little lever so I'm going to pull this down here and put tension on this chain and I should be able to like lift these smaller links off of there they should come up pretty freely like that now if the COG was worn to where there was more a wider gap between the teeth there then I wouldn't be able to like lift these up as well and so that would be an indication that that the this cassette would need be replaced I have another tool here this is called a roll-off Hg check and this is supposedly designed for Shimano hyper glide cassettes but it works basically the same way as the KMC sprocket checker again use these with a grain of salt but if you suspect that the cassette a freewheel is worn you're seeing difference in the teeth go ahead and replace it I mean you always just try a different cassette that you know is good and see if the skipping goes away and if that's the case then you know that it's a worn cassette okay so now another thing that might be an issue is stiff chain links these chain links here should pivot freely at the rivets there but sometimes you get like an old chain it's kind of like a little bit of rusty or whatever and you'll get a pair of links that are just kind of stuck or barely move and what happens is as they go through the derailleur pulleys the derailleur will kind of have to pull forward the cage will cut pop forward and pop back as those links go through and so you kind of get a popping feeling every time those links go through so what you can do is you get some oil onto the pivot point there and then to start working those links until it kind of frees up or better yet you can go ahead and just replace the chain with a brand new chain and because sometimes you'll get other pairs of links that are a little stiff and that might just be an indication that the the chain is just not in good shape so it's going to replace it anyway now another thing to be aware of I don't know the history of what's been done with your bike if you have mismatched components in your drivetrain that can also cause like auto shipping bad shipping where the chain is going to try to come between cogs if you're say running like a nine speed shifter with an eight-speaker set or you're running Shimano shifters with a peggle rid rail or something like that mismatched incompatible components like that can cause issues as well so that's something to look into make sure that everything is compatible now one other thing that might cause a change actually trying to like Auto shift and change back and forth is frame flex the frames may seem relatively stiff but they do flex a little bit and especially like if you're climbing a hill and you're standing up on the pedals and you're really pedaling the frame might be twisting look back back and forth and that might be just enough to cause the chain to try to jump up to other cogs and back so again check the trailer jump suit went on back so where it might be just slightly off and but it could be that just the frame is flexing it might be just an issue with a very lightweight frame so if that's the case then you might want to just try client Hills in a seated position with which is often better anyway anyway those are kind of the main causes for slipping skipping jumping on shifting whatever you want to call it if you found this video useful or interesting if you did please give my video a thumbs up if you guys try myself pick scribe button so you can see new videos that come out I'm always coming out with new videos I'm over on Facebook RJ the bike guy over there like that page and I post a lot of stuff over there that don't does appear the videos and I have a web page RJ the bike guy calm go over there sign up for that page I post a lot of stuff over there as well anyway thank you very much for watching

Channel: RJ The Bike Guy

Views: 2,546,187

Keywords: Bikes

Id: VzrpC7jrz8U

Length: 8min 47sec (527 seconds)

Published: Tue Aug 16 2016