4. How to Calculate Chain Length

Measure the correct length of a new bike chain.

IMPORTANT: Nuts and bolts on your bike should always be tightened to the manufacturer's specifications.
How to Calculate Chain Length
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When you purchase a new chain, it usually comes with extra length so that it is compatible with most drivetrains. How do you know how much length your bike will need? Well, it's really quite simple...

The first step is to wrap the chain around the largest sprockets on the front and rear, so that the ends meet on the largest front chainring. For this step, it really important to not run the chain through the rear derailleur.

Next, position the chain on the chainring's teeth at the tightest spot you could connect the chain. Now add one whole inner and outer link, so that you have approximately one extra inch of slack in the chain. That will be the optimal length for most systems.

In future tutorials I plan to discuss the different types of chain connectors and how to use a chain tool to break the chain. The following links provide some more helpful information.

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Discuss this topic in the Chain Forums

05/21 Single Speed Freewheel Removal Tool?

Hey Guys,

Have a BMX bike that the single speed freewheel is worn out on. The problem is that the freewheel was installed backwards. So, the notches that the freewheel tool would grab on to the freewheel to remove, are on the inside of the wheel next to the spokes. 

There are two small holes that are 180 degrees apart from each other on the outside of the freewheel. 

Is there a tool to use these holes to get the freewheel off?... 

or is there another way to remove the freewheel? 

Thanks... Read more >>

04/26 Chain ring compatibity

I have an older(vintage) bicycle, it,s a 7 speed using suntour radius parts. I want to change out my chain ring. Some say compatible with 9 or 10 speed, does it really matter? If I buy the same rings as 52/42 with the right BCD.... Read more >>

04/19 Chain skips

I have a Bianchi with SRAM Red components.  The cassette is a 11-28 10 speed.  The crank is 53-39.  I recently put on a new SRAM 10 speed chain and the chain skipped while riding when I was applying heavy pressure to the pedals.  I then put the old chain back on and the problem went away.  It feels as if the skipping is coming from the cassette rather than the crank.  I tried it again with yet another new chain and had the same problem.  Is it possible that the cassette has worn with the chain and it won't work with a new chain?  I thought I might ask before spending the money on a new... Read more >>

03/23 5 arm spider style crank

Hi, need some help to find a replacement for chainrings (if thats correct name) for a 5 arm spider style crank. Old setup was 42,34,24. Having troube to find the same again, would prefer to not have to change crank. Also like how shiny the crank it is Big Grin soapy water, alchohol wipes and a lot of elbow grease.
cheers
Read more >>

12/16 Trek 720 (1997) Drive Train (Crank & Deraileur) Replacement

My 1997 Trek 720 Multitrack was diagnosed at the local bike shop that the crankset, cassette, and chain need to be replaced.  I think the front derailer also needs replacement.  I ride for fitness so I do not care that much about the weight penalty using this older & heaver bike.  I checked my online cycling log that tracks my workouts and it was says there is over 5,000 miles over the last few years.  Its time to replace the original components on this bike.

I looked into buying a new bike and got sticker shock.  So, I started looking into buying a used bike or fix want ... Read more >>

12/02 Clicking noise/feeling from bottom bracket/pedals/chain?

Hey, lately I have been noticing an extremely annoying clicking/grinding when I am pedalling - it's mostly that I can feel it in my feet, but if it's pretty quiet around I can hear it as well. It's very inconsistent - sometimes I hear it very often, then I could go a minute or so without hearing it. I feel it in both feet, sometimes together and sometimes one at a time, but more frequently on my drive side. Generally, it's worse when putting more pressure on the pedals.
I really thought it was my bottom bracket, because there is an opening at the bottom of my frame under the bottom brac... Read more >>

11/29 Quick Chain Link??'s

Hey  Guys,

Was MTBing the other day and was about 9 miles in, a 16 mile ride, and a couple hours of daylight left, when the 9 speed KMC quick link broke on my chain. As soon as I saw what happened, I started to think, "This is going to be a long walk back!". I calmed down some and thought, "I believe I put a extra quick link in my backpack." Sure enough, I did. Whew!... I had a single speed link and a 6,7 and 8 speed quick link. I then relized I was riding a 9 speed MTB. Well, to make a long story short, I tried the 6,7 and 8 speed quick link and it seemed to work fine and got me... Read more >>

11/18 Shimano Deore rear hub and Shimano CS-HG20-7 Sprocket

Hi Everyone!

I hope you can help me. I bought a new 26" MTB rear wheel online and it has a Shimano Deore hub, I was trying to attach a new CS-HG20-7 Shimano Hyperglide Sprocket (with 7 gears and 12-28 teeth), but it seems the "Sprocket socket" (I am not sure what it is called) is slightly longer then needed, I could theoretically fit another gear cog.

Are there some kind of "spacers or washers" available? If yes, what are these things called?
Or did I mess something up? Is this normal?

I am new to bike repairs,... Read more >>

11/07 Cassette out of Order

This might be a dumb question/problem...
Today I took my cassette off and I forgot to keep it in order so now the spacers and cogs are all out of order.
Does anyone know how to reorder the spacers (some are different thicknesses) and gears correctly?
It is a SRAM Red cassette.... Read more >>

09/18 Ultegra 6800 cassette

Does anyone know if Ultegra 6800 cassette will work on Dura Ace 9000 group? If not do you know if Shimano has fixed the issues they had with the 9000 cassettes?

Thanks... Read more >>

09/14 Chain rides up on sprocket teeth

I removed and replaced the cassette on my bike (making no changes).  Now I find that when the wheel is under load the chain climbs up on the teeth of the smallest sprocket (see photo).[Image: dpy7uc.jpg]
Everything works fine with the other gears or when the wheel spins freely.  This seems to be the *opposite* effect I'd expect if the chain had stretched or the gear teeth were worn.  Instead, the pitch of the chain seems too short, not too long.  Can anyone explain what's happening and how I can fix it?... Read more >>

09/13 Chain wheel broke somehow off

Hi all. i am new here and generally also pretty new to doing anything with my bicycle myself.

I was driving my bicycle today and suddenly noticed that the rear chain ring got completely detached
from the hub and was just free rotating. I never before had a closer look at how it looks like, so I have no idea, what exactly got broken. Now it looks like that:

[img][Imag...					<a href= Read more >>

08/11 Does anyone know which Tool?

Hi All

Does anyone know the correct tool for this freewheel removal. The Park FR2 is too small.
The freewheel comes from a 1980s Raleigh Record. I've tried two local bike shops with no joy.

It has a Maillard stamp.

Thanks and Regards

M  
[Image: HVfglP.jpg]... Read more >>

07/27 Getting to the freewheel bearings?

How do I get from this
[Image: DSC05597.jpg]
[Image: freewheel_hub.jpg]

to

[Image: 275653337.jpg]

The first picture is the model I have sachs LY 94. 8 speed 12-21.  I have the freewheel and cassette off the wheel like in the ... Read more >>

07/19 Chain is loose when not pedaling

Hi, this is my first post to the forum! I have an old Focus MTB, bought it just recently second hand and I am also new to biking so please excuse me for being naive.
The problem started after the first miles with the bicycle, hearing a noise from the back. It was getting louder and louder very quickly and now, when I am pedaling everything is normal but when I stop and keep the pedals still, while on the road, the chain turns really loose and even goes out of the ring. This happens all the time. Tried with some lube and also tried to see if there is an obvious problem with the chain b... Read more >>

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