Bicycle Chainring Orientation and Chainring Installation Tips
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- čas přidán 10. 07. 2024
- 00:00 Before you start
00:30 Orientation of chainrings
02:04 Tips on installation
Before you start change chainring / replace chainrings:
1. The new chain ring for your bicycle must have the same BCD as the one you remove (and fit the crank spider). BCD refers to Bold Circle Diameter (A = distance between bolts and B = Bold Circle Diameter).
2. Always use the same speed chain rings as the rest of your components. Using 11 speed chainrings on a 10 speed system will cause the 10 speed chain to drop between the chainrings when shifted (the 11 speed chainrings are closer together than 10 speed).
3. If you want to use different size chainring, you have several issue to consider:
• Rear Derailleur total teeth capacity: Derailleurs are manufactured to handle a certain tooth a capacity equal to the difference between the numbers of teeth of the large chainring minus small chainring added to the difference in the number of teeth of the largest cog and smallest cog. A front set up of a 34/50 and a rear 11/34 give a total teeth capacity of 39 which may exceed the capacity of the rear derailleur of most double but may work on some compacts systems.
• Rear Derailleurs largest cog capacity: Derailleurs are also marked (you may have to look this up on the manufactures web site) with the maximum largest cassette it can handle. Luckily, with the advent of “shadow rear derailleurs, we can put much larger cassettes then previously.
• If you have a braze-on front derailleur, you may not be able to move the derailleur down low enough to accommodate smaller chain rings. This may also be an issue with compact drivetrains.
Bike Chainring Orientation:
1. One should use chainrings that are made by the same manufacturer as the rest of my divetrain: *
• I tend to recommend the same manufacturer because of subtle differences in mixing components.
• Chainrings are meant to be paired and using chainrings from different manufactures (for the inner and outer rings) can result in poor shifting as described below in alignment.
2. The outer chainring should be installed with the pin under the crank arm.
• If the limiting screw on the front derailleur is not adjusted perfectly and your chain falls between the outer chainring and crank, one can often get the chain back on by shifting
3. Alignment of the inner chainring:
•For most chain rings (FSA,SRAM,KMC), the writing on the ring faces outward (with the exception some of Shimano, which has the writing with the words “Shimano” on the small chain ring facing toward the bike). This assures the correct spacing between the chainrings.
•Most inner chainrings are marked either with an arrow, marking or notch to orient the chain under the crank. Even if all the teeth look the same height, they may not line up properly with the outer chainring if the arrow or notch is not lined up with the crank arm or you use chainrings from different manufactures even if the notch or marking is aligned properly as shown in the following:
• Note that when properly aligned, i.e., the notch under the crank arm, the tooth of the inner and outer chainring line up perfectly.
• As you rotate the inner chainring to the next bolt hole, the teeth line up differently.
• This is called timing.
• The video below shows how a correctly lined up small chainring allows the chain rollers to fall between the teeth when shifted and an incorrectly lined up chainriing causes the chain rollers to ride on top of the teeth resulting in poor shifting.
• This problem of rollers riding on top of the teeth also occurs with outer and inner chainrings from different manufactures.
Installation Tips:
1. Place the small chainring on the crank with the mark or notch lined up with the crank. The counter-sink for the bolt nuts faces inward.
2. Place several of the bolt nuts in the chainring and then lift the chain carefully onto the small chainring to hold it in place.
3. Place the rest of the bolt nuts on the chain ring. I prefer duel hex chainring bolts since it's much easier to use a 5 and 6 mm hex wrench rather then the chainring nut wrench . I use carbon fiber paste on the bolts rather then grease
4. Place the large chainring on the spider and attach all bolts.
5. Torque to manufacturers specifications. - Sport
Great visualization of the "timing" misalignment when orienting the small chainring incorrectly. I've known to always align the lug on the small chainring behind the crank, but I've never seen it demonstrated that clearly! Great stuff! That bike looks well loved! Happy riding from VT USA!
Thanks and yes, the bike has seen many wonderful miles. Safe cycling, Tony
Check out our complete review of chainring: docs.google.com/document/d/1PCDN1lUxSwl53JOLULXdNBJ9JS5MGW6PjHr7WZgrm08/edit?usp=sharing
Also note that the markings on most of the recent chainrings face outward with a few exceptions, but the recesses for the chainring bolts on the large chainring always face out and the recesses on the small chainring face in. Check the manufacturers specifications when in doubt.
Thanks, I learned several new things with this video.
You're Welcome. Also visit our CZcams home site at:
czcams.com/users/MrTony10speed
Regards and safe cycling, Tony
Thank you sir . I thought that was the correct alignment when I put mine back together. Now I'm certain. Thanks once again.
You're Welcome. Somehow, this seems to be overlooked when talking about chain rings.
Also visit our CZcams home site at:
czcams.com/users/MrTony10speed
Regards and safe cycling, Tony
Very constructive. Thank you. Well done.
Thanks. Regards and safe cycling, Tony
I replaced my chainrings last summer, and had this exact problem with the chain sitting on top of the small chainring. Very dangerous when switching while standing as it didn't always go onto the small ring but floated above. I learned something new today after watching your video, Now the marks are correct, hopefully this will resolve my issue. Thank you
You're Welcome. It's a topic not addressed by most videos but, as you noted, very important.
Also visit our CZcams home site at:
czcams.com/users/MrTony10speed
Regards and safe cycling, Tony
Very helpful Tony, thanks, I had not appreciated that there is a precise alignment needed. I just replaced big ring on chorus 11 (4 arm) and found small / small contact had become closer than was before. this involved mixing a campag ring with TA , and perhaps that is the issue.
I'm not sure what you mean by "found small / small contact."
Spécialités TA makes quality chainrings for their own cranksets, as well as cranksets from other manufacturers, such as Shimano, Campagnolo, SRAM and others. Things to consider when replacing chainrings are:
1. Order the correct compatible rings (Campy, Shimano, etc.) for your drivetrain.
2. Make sure the chainrings match the speed of the bike (9,10,11 or 12 speed).
3. I, personally, would replace both chainrings with either Campy or TA and make sure they "line up" as per manufacturers recommendations. Look for marks on the rings (especially the small ring) that would line up under the crank arm.
Mixing chainrings can be done, but it may be hit or miss. If you're using say, 12 speed chainring, on a 11 speed crank system, this may pose a problem. The thickness and spacing of a 12 speed vs an 11 speed or a 9 speed vs an 11 speed chainrings are different.
Is your system a double, triple, compact or single chainring drive train? Does the front derailleur shift properly (unless it's a single ring)? Let me know some more details on your problem. Regards, Tony
I have found that you can use a cassette with one larger cog then the specs for the derailleur.
That is especially true for Shimano. The manufacturer is very conservative. In other cases, the addition of a Wolf Tooth Hanger Extension will allow a bigger rear cog. Thanks for your input and regards, Tony
Dear Tony, I have put new chainrings (triple) on my bike but now the middle chainring causes to run of the chain while moving to the two smallest cogs of the cassette. The chainring wobbles and pushes the chain of between the middle and big chainring. I reassembled 5 times but same issue. Any idea?
You may have installed the wrong speed chainrings or the chainring bolts that are too long. Some 10 speed as well as 11 and 12 speed chainrings are thinner/narrower (look at the base of the chainring just below the bolt holes). For instance, when placing an 11 speed chainring on a 9 speed crank, the chainrings may sit further apart then they did on the 9 speed system, allowing the chain to fall between chainrings when shifted (as well as poor overall shifting). With the narrower chainrings, the chainring bolts may be too long and the chainrings wobble back and forth. Compare the thickness (down just below the bolt holes where the chainring sits on the crank) between your old chainrings and the new ones. The new chainrings may also be labeled with the speed (8,9,10 or 11) - is it the same as the drivetrain you're running (count the cogs in the back)? Although you can often get away with running chainrings of a different speed, it is highly recommended to get the same speed chainring as your drivetrain (and compatible with your crankset). Are the chainring bolts the same length as the old ones you used previously? Mixing different speed components is not as straight forward as it seems. Let me know how you make out. Regards, Tony
How does the pin under the crank allow you to get the chain back on if it comes off to the outside?
If the chain drops to the outside, it is kept aloft by the pin not far from the upper teeth of the smaller chainring. In such cases, sometimes (not always), one can shift back to the small chainring and have it engage. Of course you'll want to adjust the outer limiting screw either out on the road or when you get home.
Hello, if the chainrings are correctly aligned but if the notches are not behind the crank arm, is that a problem ? My front chainring have 2 position for the pin, if i put the pin behind the arm, the notches are aligned but no behind the arm.
It is possible that the chainrings are not part of the set that would come with the crank. You might need to check the manufacturers web site for the crank and chainrings.
In the mean time (while your investigating the problem), place the chainrings with the pin under the crank as you mentioned and the markings line up with each other even though they don't line up behind the crank. Take the bike for a ride and see how the front shifts.
Even though you have the right size (BCD) and speed (9,10, etc.), not all chainrings are made to work and shift smoothly on all cranks. I've seen this when replacing chainrings with others from a different manufacturer. Regards, Tony
@@tony10speed Thanks for the response.
How do I know if the writing on the chainring faces in or out?
Most chainring have the writing facing out with a vert few exceptions. The recesses for the bolts on the small chain ring face in and the recess on the large chainring face out. When in doubt, check the manufacturers website.
The teeth on the large chainring seem to vary in height - is this normal?
Modern chainrings have teeth that vary (in height) from each other. They are formed that way to enhance shifting between the different chainrings. Older chainrings from a couple of decades ago had teeth that were symmetrical as they did not have the advanced profiles in use today. However, the top of the teeth do not wear. If you notice "shark like teeth" or the grove between the teeth appears elongated or uneven, the chainring shows signs of wear and needs to be replaced. See:
czcams.com/video/sXdrOQpr-Zg/video.html
Are oval chainrings still used?
Oval chainrings were used by Bradley Wiggins and Chis Froome in their Tour de France wins but have seem to fall out of favor in recent years. But according to Tim Kerrison the performance director at Team Sky: "Power reads higher, but this does not correspond with an increase in the power actually being generated by the rider.” I, myself, try to teach new cyclists to have an even pedal stroke & cadence on the flats and to think circles as they climb which corresponds better to a round chainring. Thanks for the question, Tony
If there's no pin on the large chainring?
No pin or marking on the large chainring is something I see when restoring vintage bicycles. The markings on the chainring usually face outward as well as the recesses for the chainring bolts but how it is orientated in relation to the crank arm often becomes trail and error. Sometimes I can find info and specifications on the manufacturers website (if I'm lucky). If the chainrings are worn, I'll look for a compatible chainring set (with pin) that has the correct BCD and speed (8, 9, 10, etc.). This is a good question and maybe some of our viewers can help. Regards, Tony
I use a Q-Ring small chain ring and a SRAM RED 22 large chain ring without issues, so he is incorrect about using different manufacturers on the same crank.
In some cases, such as yours, it will work. But in others, shifting performance may suffer. I suggest the same manufacturer as a precaution rather then generalize based on one installation. Thanks for your comment, Tony