42. How to Check For Chain Wear
Demonstrates how to measure a worn out chain using Sheldon Brown’s ruler technique.
One of the most common problems I hear about is chain skip, which is when your pedal slips forward while pedaling under pressure. This is usually either caused by a stiff chain link, worn freehub body, or by a worn chain and freewheel. In this tutorial, we’ll learn how to diagnose a worn drivetrain.
Watch the stiff link tutorial first to make sure that isn’t your problem. Once you’ve ruled out a stiff link it’s time to check if your chain is actually worn. Chains will ‘stretch’ over time, because the pins and bushings start to wear, which causes them to start skipping. There are many tools available that measure chain wear (listed to the right of the video), but the easiest and most accurate way to check is by simply using a ruler.
With your chain still on the bike, place the ruler’s ’0′ inch mark directly above the center of one of your chain pins. Now count 12 complete links. A complete link equals 1 inner and 1 outer. A rivet on a new chain should line up exactly with the 12 inch mark using this method.
According to Sheldon Brown, if the rivet is less than 1/16″ past the mark, your chain is ok. If it’s between 1/16″ and 1/8″ past the mark you’ll likely need a new chain, but your sprockets should be ok. If it’s more than 1/8″ past the mark, you’ll have to replace both the chain and rear sprockets.
The reason you’d have to replace the rear sprockets is because they generally wear with the chain. While the chain is ‘stretching’, the gap between the teeth on your sprockets also gets wider and wider. This causes the chain to ride up over the teeth and slip while pedaling under pressure. If you install a new chain on an old sprocket, you’ll probably be able to see gaps of light through the teeth as shown. Here’s how to replace a cassette or a freewheel.
Your front chainrings generally won’t need replacing. Because of the larger diameter, the front chainrings usually take twice as long to wear. If worn they are very easy to spot, as they’ll start looking like shark teeth. Here’s how to replace your chainrings.
Hey folks - first off for full disclosure, I recently removed the RD from the hanger to get a look at the hanger. What I'm asking now seems to have happened after re-attaching the RD.
The bike is about a month old so I'm not considering worn out parts yet.
OK so the RD (Ultegra 6800) attaches to the hanger by one bolt. The RD pivots on that bolt. When at rest I can rotate the RD clockwise quite a bit. Just a little rotation counter clockwise. If I rotate clockwise and then let it go there is obviously a spring inside that pushes the RD back to a resting position.
Read more >>
Hi, basically I've got a problem with the front deraillieur rub on my Triban 3 road bike when in the smallest chainring on the rear and the largest chainring up front.
I've tried setting this up myself about 4 times using this guide
I just cannot seem to make the dérailleur move far enough out! I have tightened the cable as ti... Read more >>
I have cube aim pro 29 with Altus M310 FD. Recently purchased, ready to run.
Thing is I'm not satisfied how the FD is working. There is a problem
with chain rubbing.
For ex. when running in second ring upfront (where in theory there should be no rub at all in any rear shift), there is a rub depending on cable tension.
If I adjust FD in the biggest rear ring, it rubs when I shift to small ones (7,8)
and vice versa. If I adjust in smallest rear ring, it rubs when I shift to biggest (1,2,3). So basically I cannot adjust that no ... Read more >>
Today, one of my grip shifter (for the back shifting) is broken. I've only ride the bike for less than 6 months.
Unfortunately, my chain is now off the gears. So there is almost no way to get the chain back on because the shifter is not in the correct place.
Is there a quick/alternative way to adjust the shifter so I can get my chain on the gear? Thus, at least I can ride.
Or is it a good idea to simply remove the whole back derailleur and also cut some sections of chain? maybe a lot of labor for this approach.
I just want to get the bike go... Read more >>
I bought Roadmaster Granite Peak a couple of weeks back (http://www.walmart.com/ip/Roadmaster-Granite-Peak-26-Men-s-Mountain-Bike-Black/34931885).
Suddenly one by one both the gears have stopped "holding" in place.
The gear cable does move and so does the derailleurs.
A video I took is available here:
https://www.youtube.c... Read more >>
I want to replace the rear derailleur on my current mountain bike, but because it is a cheap low end full suspension, it doesn't have a hanger on the frame and only takes a bolt on derailleur. Is there anyway I can adapt the frame so that it is compatible with a hanger? the derailleurs I want all require a hanger. Thank you.... Read more >>
I just got my new Saracen Urban ESC. It has 3 gears in front and 7 at the back.
Couple of issues I have noticed when changing gears. The front derailleurs works fine when changing in to a lower ring. But when i try to shift it up I have to press the shifter twice. First time does not change the gears and make a horrible metallic sound, feels as if the bike is gonna crash.
How can I fix it?... Read more >>
I just bought a Mountain Bike that I suppose you would classify as a beginner one (Giant Revel 2) and it has been a great experience getting back into riding. Not too long ago I sort of crashed, what I mean by that is I hit the side of an object and ever since that point my front shifting is seeming to suffer. First problem was that shifting from 1st gear to 2nd gear would not always work, it just wouldn't catch and would make a clicking noise as expected. Also shifting into third would do the same. I tried adjusting the shifting knob (the one by the actual gear change on the handlebar) and no... Read more >>
Thanks for taking the time to read my problem. I have recently bought a new bike. It is around 3 weeks old and done 112 miles on it. Recently it has started taking ages to shift up a gear on the rear cassette and occasionally it feels like it is trying to change gear on its own. The shift down is fine at the moment. In another 3 weeks the bike will have a 6 week free service. Is it worth waiting till then to let the professionals look at it or is it a quick fix I can do myself? I want to keep it in tip top condition so dont want it getting any worse or even damage it by putting mo... Read more >>
I'm trying to do some basic bike repairs, but I've stumbled upon a problem I cannot solve.
I have a Trek Lexa women's road bike (~3 years old) with Shimano derailleurs. It was in need of a tune-up as shifting between gears was not smooth and the chain was rubbing the bracket; however it was capable of shifting. I started by unhooking the shifter cable and adjusting the high and low limits of the rear derailleur. When I hooked the cable back up (tightened the rear adjustment screw, pulled on the cables, tightened the cable as much as I could while the gears we... Read more >>
I've watched hours of tutoring videos all over the internet in search for an answer. This forum is probably my last shot at it. The gears on the left (for the front derailleur) don't change the gears on my bike, because the shifter cable is out. I've been trying to reinsert my shifter cable for my FD, but only gear one and two work, and it's too stiff for the third gear. Ahhhh! Please help!!... Read more >>
Rear Derailleur shifter: Falcon Index System thumb shifter.
The high and low limits are set correctly because I can shift through all the gear with no problem. I just have to hold the shifter in place. If I let go, it will move all the way to high gear (small cog). It won't stay in anything but the highest gear by itself.... Read more >>
I recently purchased a Genesis Roadtech bike from Wal-Mart. It's a road bike but I have no idea how to use the shifters on this bike. The image is where the shifters are located.
I'm just getting into cycling so some of this stuff is still very new to me.
Thank you in advance for help advice.... Read more >>
I currently ride a Giant Revolt 2, 2014 model Cyclocross bike.
Last week during my commute to work I lost a spacer from my rear cassette so had it repaired by a local guy who is a friend of mine.
He managed to get every gear sweet bar the highest (small cog) on the rear cassette, it shifts nicely from the second smallest cog down to the smallest cog but it won't go back up - only on that one lowest gear.
He took it to his workshop over night and fit a new cassette and removed a link from the chain as the chain was still slack but that... Read more >>
I have a Sturmey Archer gears on my bike with a following shifter:[attachment=5222]
However I would like to change this shifter for modern one -the one I currently have is a bit rusty and its though to change gears sometimes.I have found this model:
3 SPEED NIMBUS SHIFTER
FITS 22.2MM BARS.
Will this shifter be suitable to replace the old one?
Thanks... Read more >>