Tech Tip: The Dos & Don'ts When Purchasing & Fitting A New Drive Chain

Tech Tip: The Dos & Don'ts When Purchasing & Fitting A New Drive Chain

When it comes down to a worn or knackered drive chain there are a couple of points that one must take into consideration before purchasing a replacement

Although replacing a drive chain does appear to be straight forward, today we will cover the dos and don'ts when placing an order for a replacement drive chain

Further below you will also find tips on how to cut your new drive chain to fit your specific application 

The information below can be used here on the Classic British Spares site or perhaps other sites when selecting a new chain..

Lets get started..


Selecting a chain - "The Dos"

Triumph Chain Parts Catalog


In order to obtain the correct chain length and pitch, you will need to take the time to inspect and document what your motorcycle currently has fitted to it 

Spending the extra time doing so will make your chain purchase and installation a more positive experience 

Lets go over a few "Dos" which will help you in the short and long term


  • Obtain your year, make and model of motorcycle that will require a new drive chain

  • Verify how many teeth on the front and rear drive sprockets currently fitted to your machine

  • Verify the chain count along with the correct chain diameter (width)

  • Refer to a parts book or workshop manual to reference the stock chain length assuming that all parts are “correct” for your application

  • Have the proper tools on hand to cut a chain to any given length


Selecting a chain - "The Don'ts"


Triumph Workshop Manual Chain Specs

Now that we know what to "do", lets go over "the don'ts


  • Do not assume which type of chain you need without consulting your motorcycle

  • Do not rely strictly on a parts book to tell you which chain size you need - (parts get changed over the years)

  • Do not blindly purchase a chain "assuming" that it will fit from the start


Cutting chain - quick tips

Assuming that you have followed the steps above and you now have the correct chain in hand, you may find that you need to cut the chain for your specific application

If that happens to be the case, below we will cover how to cut a motorcycle drive chain 

 How To Cut A Final Drive Motorcycle Chain - Steps

 How to cut a chain in 4 easy steps 

Cutting a new drive chain does require the correct tools such as a chain breaker, however if do not have a chain breaker you can use the "bench grinder, hammer and a punch method" as an alternative

The bench grinder method

  1. Mark the desired chain length in which you need to cut
  2. Grind the rivet down 
  3. Take your hammer and punch and apply blunt force over the ground river  (you will be able to see witness marks) and hammer the pin out 
  4. Verify that you have cut the correct link (if done correctly you should have an inner link exposed NOT an outer link - see below photo for details)

Remember, safety first!

 The chain breaker method

Chain Breaker Tool by EMGO


If you have a chain breaker handy this is by far the easiest, cleanest and quickest way to properly size your chain 

Just like steps 1-4 above, a chain breaker tool pushes the river pin out without having to grind or hammer the pin out... easy!

Correct vs Incorrect Cutting Of Drive Chain

 What a chain should and should not look like once the chain has been cut

When cutting drive chains it is vital to cut the correct link of chain, I have seen many mistakes when folks cut the incorrect portion of the chain...

This is where most folks "give up" 

Cut the inside chain link NOT the outside (see the photo above)

On your first try you may make this simple yet confusing mistake, if you study the chain, you will find which rivet to remove or cut to expose the inside link

 If you have cut the wrong link of chain it’s not the end of the world, simply cut the chain back 1 link to where the inner chain link is exposed and use a half-link to make up the difference 


Your chain, your responsibility

Renold Motorcycle Chains

As a parts seller there is only so much we can do to help our customers in selecting a proper chain

We cannot see through the phone nor do we “assume” what you “might” need so it is very important to follow the steps above

Chains come in “pre/cut” generic link sizes (107,110,120,etc) from our manufacture which includes Renold and KMC so be prepared to cut a chain specific for your application

Unfortunately we will not be able to cut or prepare any drive chain other than what is supplied to us from our manufacture but we would be happy to assist you

Learning how to cut a motorcycle chain is a good skill to have


Chains and tools for purchase

 Renold Chain & Chain Breaker Tools


Should you need a new replacement chain or tools we have a large selection for most vintage Triumph, BSA and Norton motorcycles

View the chart below showcasing our current stock  - click on the "click here" text to make a purchase

*All drive chains, masterlinks and half-links both Renold and Taiwan are the "narrow / thin wall" variety as OEM

Part Type Brand Link
Motorcycle Chain (all sizes) Renold (Enlgland) Click Here
Masterlinks & Half-links Renold & KMC Click Here
Chain Breaker EMGO (Taiwan) Click Here


Thanks for reading today


Should you have any questions about today's Tech Tip blog post or you would like to leave us a comment, please join in on the conversation below commenting below

Click here for more Tech Tips blog post like this one 

Thanks for reading, ride safe! 


  • Howard

    Does anyone know if the original Monobloc float bowl covers will fit the newly made Monobloc carbs?
    Sadly they chose not to use exactly the same wording on the new covers as on the old which is a real giveaway as to originality. Does it matter that they are no longer actually made in Birmingham?

  • Howard

    I have two good condition chains. Rather than use spray grease which goes everywhere and attracts dust and dirt I now swap the chains on a regular basis using the fitted chain to pull the replacement chain over the front sprocket. With practice it takes only a few minutes to swap chains. The removed chain gets soaked and scrubbed with petrol/gas hung and left to dry before submerging fully in engine oil until needed. When next required I hang the chain over the oil container and leave for 24 hours so the oil fully drips away. Chain is now ready to go on the bike. If like me you do a low mileage on your classic bike (67 Bonneville) regular changes are not that often. The chain runs really freely with no mess and no need to use the Triumph onboard chain oiler which is also rather messy. I recommend using only top quality chains (Renold is best) as you may be surprised just how quickly cheap chains can stretch and accelerate the wear on the sprockets. I also suggest not continually snapping the throttle open boy racer style. Embarrassed to admit at 17 with my 650 Thunderbird I ended up stripping the left primary side crankshaft splines. New crank or very expensive weld and re machine required plus complete engine rebuild. I consequently treat my 67 Bonneville with far more love and gentle riding.

  • Zniewski Workshop

    I bet I have five chain breakers with broken pins – all high quality shop tools – and not ONE of the makers is still in business. I assume that ill be the case for the ones sold today. Why do they not come with a couple extra pins? Does CBS sell replacement pins?
    Guess I should turn up a few from 4130 to replace my broken ones.

  • Irish Swede

    If you are too cheap to buy a chain-breaker, maybe motorcycling is not the right hobby for you. With the chain breaker and a few spare chain links you can make repairs “on the road” if need be (would you carry a “grinder” with you otherwise?)

    As to measurements: also check the WIDTH of the original chain on the bike.
    There are differences depending on manufacturer. An example:
    Reynold chains are narrower. This is critical on Triumph 350cc and 500cc twins, which have a more narrow “tunnel” leading to and from the gearbox drive sprocket.
    Too wide a chain will cause a “clicking” sound every time the chain’s master link goes through there. Eventually this will cause damage to the case.

    Always, ALWAYS carry one or two spare “master links” with you.
    Chains have been known to lose one now and then.
    I carry one on my bike’s key ring, just to be certain I always have at least one.

  • Classic British Spares

    @Frank – correct

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