All

Tooth Count - the number of teeth on the chainring, the higher the number the harder the gear.

Between Adjacent Bolt Holes - the measurement from the centre of any bolt hole to the centre of an adjacent one, if this measurement is the same as that of your crankset and the bolt count is the same then the chainring should fit.

BCD - stands for Bolt Circle Diameter (sometimes referred to as PCD - Pitch Circle Diameter) and is the technical way to determine whether the chainring fits your crankset. To calculate, multiply the distance between adjacent holes (in mm) by 1.709 (you’ll likely need to round the resulting number up or down a little).

Bolt Count - the number of bolts securing the chainring to the chainset. As with the BCD, this must be the same as your chainset.

Chain Width - 3/32” is the standard width for double and triple chainsets, wherease 1/8” chainrings are only found on single ring chainsets, generally for track / singlespeed use and can only be used with a wide 1/8" chain.

Intended Speed - the number of cogs at the back the chainring was designed to be used with. We refer to it as ‘intended’ speed as most double and triple chainsets will actually work with different speeds than originally intended, but the further away you get from the intended speed the more likely you are to experience minor setup issues. The exception being some chainrings intended for 10 speed use or higher, with these it’s better to stick to the intended speed.

Tooth Count - the number of teeth on the chainring, the higher the number the harder the gear.

Between Adjacent Bolt Holes - the measurement from the centre of any bolt hole to the centre of an adjacent one, if this measurement is the same as that of your crankset and the bolt count is the same then the chainring should fit.

BCD - stands for Bolt Circle Diameter (sometimes referred to as PCD - Pitch Circle Diameter) and is the technical way to determine whether the chainring fits your crankset. To calculate, multiply the distance between adjacent holes (in mm) by 1.709 (you’ll likely need to round the resulting number up or down a little).

Bolt Count - the number of bolts securing the chainring to the chainset. As with the BCD, this must be the same as your chainset.

Chain Width - 3/32” is the standard width for double and triple chainsets, wherease 1/8” chainrings are only found on single ring chainsets, generally for track / singlespeed use and can only be used with a wide 1/8" chain.

Intended Speed - the number of cogs at the back the chainring was designed to be used with. We refer to it as ‘intended’ speed as most double and triple chainsets will actually work with different speeds than originally intended, but the further away you get from the intended speed the more likely you are to experience minor setup issues. The exception being some chainrings intended for 10 speed use or higher, with these it’s better to stick to the intended speed.

Tooth Count - the number of teeth on the chainring, the higher the number the harder the gear.

Between Adjacent Bolt Holes - the measurement from the centre of any bolt hole to the centre of an adjacent one, if this measurement is the same as that of your crankset and the bolt count is the same then the chainring should fit.

BCD - stands for Bolt Circle Diameter (sometimes referred to as PCD - Pitch Circle Diameter) and is the technical way to determine whether the chainring fits your crankset. To calculate, multiply the distance between adjacent holes (in mm) by 1.709 (you’ll likely need to round the resulting number up or down a little).

Bolt Count - the number of bolts securing the chainring to the chainset. As with the BCD, this must be the same as your chainset.

Chain Width - 3/32” is the standard width for double and triple chainsets, wherease 1/8” chainrings are only found on single ring chainsets, generally for track / singlespeed use and can only be used with a wide 1/8" chain.

Intended Speed - the number of cogs at the back the chainring was designed to be used with. We refer to it as ‘intended’ speed as most double and triple chainsets will actually work with different speeds than originally intended, but the further away you get from the intended speed the more likely you are to experience minor setup issues. The exception being some chainrings intended for 10 speed use or higher, with these it’s better to stick to the intended speed.

Thread Type - this must match the bottom bracket thread on your frame. The 3 common thread types on classic and vintage bikes are English (also known as British or ISO), Italian & French, and are usually (not always!) found on frames built in their respective countries. If you're replacing a bottom bracket the cups should have the thread type stamped on one of them, if not there are a couple of things to look at; bottom bracket shell width (English & French = 68 mm, Italian = 70 mm) & drive side cup thread direction (English = left, Italian & French = right). The only curveball to watch out for here, although pretty uncommon, are Swiss threads (also found on some French frames, Motobecanes being one) which will have the same shell width & thread direction as an English thread frame but the actual thread pitch will be different. If none of the above matches what you have, there are a few lesser known varieties that will require some further research.

Axle Length - your crankset dictates the axle length you need and the recommendation should be used to avoid issues with chainline. If you're replacing a bottom bracket that works perfectly then this can be matched, otherwise you'll need to check the manufacturers spec, a good resource for older bikes is Velobase.

Axle Type - you can tell which type of axle you need by looking at the shape of the bottom bracket hole in your crankset. For square tapers, the ISO introduced a standard for European makers in the early 90s, JIS then did the same in Asia. Before then it was not so simple, and although there is a degree of interchangeability, the best way to make sure you have the right axle is to stick to the same brand from the same era, ideally the proprietary model.

Bearing Size - most bottom brackets use 1/4" bearings, but there are some that use smaller sizes so it's advisable to measure your old ones or check with a local bike shop to be sure.

Retainer Type - you can use any type of retaining cage in any bottom bracket as long as the bearing sizes are correct.

Tooth Count - the number of teeth on the chainring, the higher the number the harder the gear.

Between Adjacent Bolt Holes - the measurement from the centre of any bolt hole to the centre of an adjacent one, if this measurement is the same as that of your crankset and the bolt count is the same then the chainring should fit.

BCD - stands for Bolt Circle Diameter (sometimes referred to as PCD - Pitch Circle Diameter) and is the technical way to determine whether the chainring fits your crankset. To calculate, multiply the distance between adjacent holes (in mm) by 1.709 (you’ll likely need to round the resulting number up or down a little).

Bolt Count - the number of bolts securing the chainring to the chainset. As with the BCD, this must be the same as your chainset.

Chain Width - 3/32” is the standard inner chain width for 5 to 8 speed, above that requires a slightly narrower 11/128” chain. 1/8” chainrings are only found on single ring chainsets, generally for track / singlespeed use and can only be used with a wide 1/8" chain.

Intended Speed - the number of cogs at the back the chainring was designed to be used with. We refer to it as ‘intended’ speed as most double and triple chainsets will actually work with different speeds than originally intended, but the further away you get from the intended speed the more likely you are to experience minor setup issues. The exception being some chainrings intended for 10 speed use or higher, with these it’s better to stick to the intended speed.

Tooth Count - the number of teeth on the chainring, the higher the number the harder the gear.

Between Adjacent Bolt Holes - the measurement from the centre of any bolt hole to the centre of an adjacent one, if this measurement is the same as that of your crankset and the bolt count is the same then the chainring should fit.

BCD - stands for Bolt Circle Diameter (sometimes referred to as PCD - Pitch Circle Diameter) and is the technical way to determine whether the chainring fits your crankset. To calculate, multiply the distance between adjacent holes (in mm) by 1.709 (you’ll likely need to round the resulting number up or down a little).

Bolt Count - the number of bolts securing the chainring to the chainset. As with the BCD, this must be the same as your chainset.

Chain Width - 3/32” is the standard inner chain width for 5 to 8 speed, above that requires a slightly narrower 11/128” chain. 1/8” chainrings are only found on single ring chainsets, generally for track / singlespeed use and can only be used with a wide 1/8" chain.

Intended Speed - the number of cogs at the back the chainring was designed to be used with. We refer to it as ‘intended’ speed as most double and triple chainsets will actually work with different speeds than originally intended, but the further away you get from the intended speed the more likely you are to experience minor setup issues. The exception being some chainrings intended for 10 speed use or higher, with these it’s better to stick to the intended speed.

Extension Length (ctc)* - we measure from the centre of the handlebar clamp to the centre of the shaft, to the point where the stem bolt passes through, to the nearest 5 mm. We always take this measurement in a straight line through the middle of the extension, not along the top. In some cases the stem may be stamped with a different extension length as some manufacturers measured differently, but we always use our own measurement for consitency.

Quill Size - the most common size for classic and vintage road bikes is 1", this should be the same as the outside diameter of your fork's steerer column. Oversized steerers found on mountain bikes and later road bikes will be either 1 1/8" or 1 1/4".

Steerer Size (ID) - this is the most important measurement when checking the stem fits your bike. This should match the measurement of the inside of your fork's steerer column, where the stem will be inserted. The standard size for road quill stems was 22.2 mm, or 22.0 mm in France until the 1980s.

Total Shaft Height - measured from the top where the expander bolt head sits, to the bottom of the stem's shaft. To give you an idea of how high the stem can be set, there should be an absolute minimum of 50 mm inserted into the fork steerer, although most stems come with a 'minimum insertion line' to help with this.

Clamp Size - this should match the outside diameter of your handlebars and should be as close as possible to ensure a good and safe fit.

Pedal Type - this is just a guide to give you an idea of the pedal type, but any pedal can technically be used for any purpose. Track pedals are designed without the pointed 'quill' for safety though, so it's best to only use track pedals for this purpose. Most track pedals, along with quill & aero road pedals are designed to be used with toe clips & straps for best performance.

Pedal Threads - this must match the thread on your cranks. Sometimes it's stamped on the end of the crank arm, but most bikes use a standard thread of 9/16” x 20 tpi. The exceptions being older French bikes, bikes with cheaper one-piece type chainsets and Shimano’s Dyna Drive system (easily identifiable as the pedal holes are about an inch wide!).

Bottom Bracket Thread Type - this must match the thread of your bottom bracket for the lockring to fit.

Thread Direction - most bottom brackets only have an adjustable cup on the non-driveside of the bike, so lockrings mostly thread to the right (clockwise), regardless of the thread type. However, some bottom brackets have adjustable cups on both sides so the thread direction may be different.

Thickness - this is rounded to the nearest 0.5 mm.

Tooth Count - the number of teeth on the chainring, the higher the number the harder the gear.

Between Adjacent Bolt Holes - the measurement from the centre of any bolt hole to the centre of an adjacent one, if this measurement is the same as that of your crankset and the bolt count is the same then the chainring should fit.

BCD - stands for Bolt Circle Diameter (sometimes referred to as PCD - Pitch Circle Diameter) and is the technical way to determine whether the chainring fits your crankset. To calculate, multiply the distance between adjacent holes (in mm) by 1.709 (you’ll likely need to round the resulting number up or down a little).

Bolt Count - the number of bolts securing the chainring to the chainset. As with the BCD, this must be the same as your chainset.

Chain Width - 3/32” is the standard width for double and triple chainsets, wherease 1/8” chainrings are only found on single ring chainsets, generally for track / singlespeed use and can only be used with a wide 1/8" chain.

Intended Speed - the number of cogs at the back the chainring was designed to be used with. We refer to it as ‘intended’ speed as most double and triple chainsets will actually work with different speeds than originally intended, but the further away you get from the intended speed the more likely you are to experience minor setup issues. The exception being some chainrings intended for 10 speed use or higher, with these it’s better to stick to the intended speed.

Tooth Count - the number of teeth on the chainring, the higher the number the harder the gear.

Between Adjacent Bolt Holes - the measurement from the centre of any bolt hole to the centre of an adjacent one, if this measurement is the same as that of your crankset and the bolt count is the same then the chainring should fit.

BCD - stands for Bolt Circle Diameter (sometimes referred to as PCD - Pitch Circle Diameter) and is the technical way to determine whether the chainring fits your crankset. To calculate, multiply the distance between adjacent holes (in mm) by 1.709 (you’ll likely need to round the resulting number up or down a little).

Bolt Count - the number of bolts securing the chainring to the chainset. As with the BCD, this must be the same as your chainset.

Chain Width - 3/32” is the standard width for double and triple chainsets, wherease 1/8” chainrings are only found on single ring chainsets, generally for track / singlespeed use and can only be used with a wide 1/8" chain.

Intended Speed - the number of cogs at the back the chainring was designed to be used with. We refer to it as ‘intended’ speed as most double and triple chainsets will actually work with different speeds than originally intended, but the further away you get from the intended speed the more likely you are to experience minor setup issues. The exception being some chainrings intended for 10 speed use or higher, with these it’s better to stick to the intended speed.

Chainring Count - the number of chainrings the bolts are designed to fit, this must be the same as the number of chainrings you are using.

Crank Type - Most cranks require the standard 5-bolt sets that consist of 5 bolts with backs that slot into the rear of the crank spider, there are also some less common cranks with 3 arms that require the 3-arm chainring bolts. Specialites T.A. 'Professionel 5 Vis' and Stronglight '49D' type cranks require special 50.4 BCD chainring bolts that are specific to these crank designs.

Mount Type - most bolts simply fix the chainring to the crank, but some cranks require bolts to fix one chainring to another.

Back Nut Length (Excluding Head) - the more chainrings your crank has the longer the bolts and nuts need to be. We exclude the head part from the measurement (the bit that often sits recessed in back of the chainring).

Chainring Count - the number of chainrings the bolts are designed to fit, this must be the same as the number of chainrings you are using.

Crank Type - Most cranks require the standard 5-bolt sets that consist of 5 bolts with backs that slot into the rear of the crank spider, there are also some less common cranks with 3 arms that require the 3-arm chainring bolts. Specialites T.A. 'Professionel 5 Vis' and Stronglight '49D' type cranks require special 50.4 BCD chainring bolts that are specific to these crank designs.

Mount Type - most bolts simply fix the chainring to the crank, but some cranks require bolts to fix one chainring to another.

Back Nut Length (Excluding Head) - the more chainrings your crank has the longer the bolts and nuts need to be. We exclude the head part from the measurement (the bit that often sits recessed in back of the chainring).

Chainring Count - the number of chainrings the bolts are designed to fit, this must be the same as the number of chainrings you are using.

Crank Type - Most cranks require the standard 5-bolt sets that consist of 5 bolts with backs that slot into the rear of the crank spider, there are also some less common cranks with 3 arms that require the 3-arm chainring bolts. Specialites T.A. 'Professionel 5 Vis' and Stronglight '49D' type cranks require special 50.4 BCD chainring bolts that are specific to these crank designs.

Mount Type - most bolts simply fix the chainring to the crank, but some cranks require bolts to fix one chainring to another.

Back Nut Length (Excluding Head) - the more chainrings your crank has the longer the bolts and nuts need to be. We exclude the head part from the measurement (the bit that often sits recessed in back of the chainring).

Crank Thread - 22 mm is the standard thread for almost all cotterless cranks, the only exceptions are some Stronglight cranks made up until the early 1980s, and Specialites T.A. Campagnolo produced some self-extracting crank bolts with covers that had a reverse thread.

Chainring Count - the number of chainrings the bolts are designed to fit, this must be the same as the number of chainrings you are using.

Crank Type - Most cranks require the standard 5-bolt sets that consist of 5 bolts with backs that slot into the rear of the crank spider, there are also some less common cranks with 3 arms that require the 3-arm chainring bolts. Specialites T.A. 'Professionel 5 Vis' and Stronglight '49D' type cranks require special 50.4 BCD chainring bolts that are specific to these crank designs.

Mount Type - most bolts simply fix the chainring to the crank, but some cranks require bolts to fix one chainring to another.

Back Nut Length (Excluding Head) - the more chainrings your crank has the longer the bolts and nuts need to be. We exclude the head part from the measurement (the bit that often sits recessed in back of the chainring).

Cap Type - we refer to the classic cycling cap type as summer/under helmet, although they can of course be used all year round. When worn under a helmet they provide comfort, sun protection and are sweat-wicking too. Winter hats will usually cover the ears and are referred to as 'Belgian' caps. Baseball caps were often worn by support teams or sold as branded merchandise.

Construction - the number of panels the cap body is made up of, not including the peak.

Pit to Pit - this measurement is taken from the centre of one armpit to the other, across the chest with the jersey laid flat.

Top to Bottom - this will always be from the very top of the collar to the very bottom hem, we provide measurements for both the front and back, always taken with the jersey laid flat.

Shoulder Seam to Sleeve End - this measurement is taken from the shoulder seam down to the very end of the sleeve on the outside.

Across Neck - for consistency on all neck shapes we gather the front and back together and lay them flat, then measure across the stitching (as shown in the supporting photos).

Across Sleeve End - measured across the sleeve end, laid flat.

Pit to Pit - this measurement is taken from the centre of one armpit to the other, across the chest with the jersey laid flat.

Top to Bottom - this will always be from the very top of the collar to the very bottom hem, we provide measurements for both the front and back, always taken with the jersey laid flat.

Shoulder Seam to Sleeve End - this measurement is taken from the shoulder seam down to the very end of the sleeve on the outside.

Across Neck - for consistency on all neck shapes we gather the front and back together and lay them flat, then measure across the stitching (as shown in the supporting photos).

Across Sleeve End - measured across the sleeve end, laid flat.

Pit to Pit - this measurement is taken from the centre of one armpit to the other, across the chest with the jersey laid flat.

Top to Bottom - this will always be from the very top of the collar to the very bottom hem, we provide measurements for both the front and back, always taken with the jersey laid flat.

Shoulder Seam to Sleeve End - this measurement is taken from the shoulder seam down to the very end of the sleeve on the outside.

Across Neck - for consistency on all neck shapes we gather the front and back together and lay them flat, then measure across the stitching (as shown in the supporting photos).

Across Sleeve End - measured across the sleeve end, laid flat.

Pit to Pit - this measurement is taken from the centre of one armpit to the other, across the chest with the jersey laid flat.

Top to Bottom - this will always be from the very top of the collar to the very bottom hem, we provide measurements for both the front and back, always taken with the jersey laid flat.

Shoulder Seam to Sleeve End - this measurement is taken from the shoulder seam down to the very end of the sleeve on the outside.

Across Neck - for consistency on all neck shapes we gather the front and back together and lay them flat, then measure across the stitching (as shown in the supporting photos).

Across Sleeve End - measured across the sleeve end, laid flat.

Pit to Pit - this measurement is taken from the centre of one armpit to the other, across the chest with the jersey laid flat.

Top to Bottom - this will always be from the very top of the collar to the very bottom hem, we provide measurements for both the front and back, always taken with the jersey laid flat.

Shoulder Seam to Sleeve End - this measurement is taken from the shoulder seam down to the very end of the sleeve on the outside.

Across Neck - for consistency on all neck shapes we gather the front and back together and lay them flat, then measure across the stitching (as shown in the supporting photos).

Across Sleeve End - measured across the sleeve end, laid flat.

Cap Type - we refer to the classic cycling cap type as summer/under helmet, although they can of course be used all year round. When worn under a helmet they provide comfort, sun protection and are sweat-wicking too. Winter hats will usually cover the ears and are referred to as 'Belgian' caps. Baseball caps were often worn by support teams or sold as branded merchandise.

Construction - the number of panels the cap body is made up of, not including the peak.

Cap Type - we refer to the classic cycling cap type as summer/under helmet, although they can of course be used all year round. When worn under a helmet they provide comfort, sun protection and are sweat-wicking too. Winter hats will usually cover the ears and are referred to as 'Belgian' caps. Baseball caps were often worn by support teams or sold as branded merchandise.

Construction - the number of panels the cap body is made up of, not including the peak.

Position - some brake pads are designed for front or rear use only, although most can be used on either. If they are front or rear specific they should only be used in that position.

Brake Fit - brake pads are specific to the type of brake so you need to use the correct ones.

Compatibility - the brake pad holders (also known as shoes) the inserts are designed to fit.

Rim Type - some wheel rims such as ceramic or carbon require brake pads to be made of specific compounds. If you have steel rims you can use pads designed for alloy rims but you will get much better performance when using the correct pads.

Brake Fit - most brake pads are specific to the type of brake so you need to use the correct ones.

Compatibility - the brake pad holders (also known as shoes) the inserts are designed to fit.

Rim Type - some wheel rims such as ceramic or carbon require brake pads to be made of specific compounds. If you have steel rims you can use pads designed for alloy rims but you will get much better performance when using the correct pads.

Optimal Speed - the ideal number of rear cogs, based on the outer width of the chain and the cog width it was designed for. For 6 Speed Shimano Uniglide a 5/6 spd chain will perform best.

Shifting System(s) - indexed shifters 'click' when you change gear. For 9 speed upwards (or Suntour Accushift), to guarantee the best performance we recommend using the dedicated chain. Otherwise, for 8 speed and below, or any speed when using friction shifting (non-index), you just need the correct outer width.

Outer width - measured across the rivets at the widest point, these are the approximate widths for different speed setups (up to 4 speed is also dependent on cog width):

Cog Width - the gap between the inner plates allows for different rear cog/sprocket widths. 3/32" is the standard for 5 to 8 speed, above that it’s 11/128”. For 4 speed or less, 3/32” and 1/8” were both used, for the latter you will need a 1/8” chain. A wider 3/16" moped chain can be used as a heavy duty opton for single cog setups if required).

Chain pitch - the distance between the rivets/pins. All chains will be 1/2" with two exceptions; 3/16" (“inch pitch”) for very early track bikes, or Shimano's short lived 10 mm pitch system from the 70s/80s.

Number of links - if you're unsure how many you need, measure your old chain (each link has two rivets) or one with a similar setup to yours.