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Zeus Gran Sport / Nisi Super Corsa Vintage Tubular Road Wheels
£275.00
✓ Original vintage wheels - produced in the 1970s
✓ Lightweight for the era - just 1.9 kg (for the pair)
✓ Suitable for historic cycling events such as L'Eroica
✓ Professionally serviced, cleaned & tub glue removed*
✓ Worldwide shipping
Zeus Gran Sport wheels built with Nisi Super Corsa rims, the hubs hailing from Spain and in production during the 1970s. Made from aluminium/steel and weighing in at 1.9 kg - pretty lightweight for a pair of wheels at that time. A fine choice for keeping your vintage bike authentic, but also great for any other compatible bike too.
If you're taking part in L'Eroica or a similar vintage event, these are fully compliant - so rest assured, the pre-1987 police won't lock you up for having the wrong wheels!
The wheels have been serviced, excess glue residue removed and graded as very good condition, but do take a good look at the detailed photos so you can see the cosmetic condition before you buy.*Heavily bonded glue residue may be left on the rims as new glue can be applied to this. If using tape please check the brand guidelines as some manufacturers recommend removing all traces of old glue, even if extremely well bonded.
OVERVIEW
Rim Condition - Very Good
Hubs - Zeus Gran Sport
Rims - Nisi Super Corsa
Production Era - 1970s
Material - Aluminium / Steel
Weight - 1.905 kg
Stock Code - U-W-PR66V
TECHNICAL INFO
Rim Size - 28"/700c Tubular
Bike Type - Road
Drilling (F/R) - 36/36 Hole
Spacing (O.L.D.) (F/R) - 100 mm / 122 mm
Speed - 5 Speed, 6 Speed
Sprocket Fitting - Screw On (English/ISO: 1.375 x 24 TPI)
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▼SHIPPING, TAXES & RETURNS
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We've been safely sending orders around the world since 2010. There's a handy shipping calculator on the shopping cart page so you can see the cost of postage as soon as you've added it to your basket. Your order will be carefully packed and sent with tracking & insurance, we despatch most orders within 2-3 days but larger items and orders placed before the weekend can take an extra day or two to process.
We accept returns, please notify us within 14 days and ensure the item arrives back with us no later than 30 days after the order was received.
We don't charge VAT, however, if buying from outside of the UK please remember that there may be import fees to pay directly to the delivery company before receiving the order. Unfortunately we can’t advise on the exact costs as it varies from country to country, so please check your national rates before purchasing.
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▼HELP SECTION
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Rim Size - this should match the size your bike frame is designed to fit. Standard/full size tubulars only come in one wheel size, these are often referred to as 28" or 700c (sometimes even 27"). These are all the same size, the next size down is 26", so any rims larger than 26" will be standard/full size tubulars.
Bike Type - this is really just a guide, as technically any wheels can be used on any bike as long as everything's compatible. Within reason of course - we wouldn't recommend riding a set of skinny tubular road wheels down a mountain!
Drilling (F/R) - the number of spokes in each wheel (front/rear).
Spacing (O.L.D.) (F/R) - the width of the hubs measured at their widest point, from the outside of the locking end nuts (O.L.D. = Over Locknut Dimension), not including the hub axle. These measurements need to match the inside of your frame and fork’s dropouts. Steel frames can be stretched or squeezed a few mm but it's always best to avoid this if possible, aluminium or carbon frames should never be stretched.
Speed - the number of cogs the rear hub was designed to be used with.
Sprocket Fitting - for cassette hubs this refers to the spline pattern (the shape of the cogs where they slide on to the hub) and this must match the cassette you intend to use. With freewheel hubs it refers to the thread, ISO is the modern standard and is almost exactly the same as older English/British and Italian thread, allowing you to mix and match between these thread types as long as it's not going to be under extreme force, in which case it's best to stick to an exact match. Freewheel hubs with a French thread must be used with a French threaded freewheel.
Zeus Gran Sport Twin Bolt Vintage 27.0 mm Seatpost
£75.00
✓ Original part - produced in the 1970s
✓ Suitable for historic cycling events such as L'Eroica
✓ Professionally checked & cleaned
✓ Worldwide shipping
Zeus Gran Sport seatpost, hailing from Spain and in production during the 1970s. Made from steel and weighing in at 318 grams. A fine choice for keeping your vintage bike authentic, but also great for any other compatible bike too.
If you're taking part in L'Eroica or a similar vintage event, this is fully compliant - so rest assured, the pre-1987 police won't lock you up for having the wrong seatpost!
The seatpost's been carefully cleaned, thoroughly checked by one of our mechanics and graded as mint condition, but do take a good look at the detailed photos so you can see the cosmetic condition before you buy.OVERVIEW
Production Era - 1970s
Country - Spanish
Material - Steel
Weight - 318 g
Stock Code - U-SP122V
TECHNICAL INFO
Seatpost Diameter - 27.0 mm
Length (Centre of Rails to Base) - 170 mm
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▼SHIPPING, TAXES & RETURNS
-
We've been safely sending orders around the world since 2010. There's a handy shipping calculator on the shopping cart page so you can see the cost of postage as soon as you've added it to your basket. Your order will be carefully packed and sent with tracking & insurance, we despatch most orders within 2-3 days but larger items and orders placed before the weekend can take an extra day or two to process.
We accept returns, please notify us within 14 days and ensure the item arrives back with us no later than 30 days after the order was received.
We don't charge VAT, however, if buying from outside of the UK please remember that there may be import fees to pay directly to the delivery company before receiving the order. Unfortunately we can’t advise on the exact costs as it varies from country to country, so please check your national rates before purchasing.
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▼HELP SECTION
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Seatpost Diameter - this needs to match the internal diameter of your frame’s seat tube closely, it should be possible to insert the seatpost without force but the fit should be tight enough so it doesn’t just drop in, with no play once inserted. If you have a post that fits the measurement should be stamped somewhere near the bottom., otherwise you’ll need to measure with a caliper or seatpost sizing tool as seatpost diameters go up in 0.2 mm increments.
Length (Centre of Rails to Base) - measured from where the centre of the saddle rails will sit once installed, all the way to the bottom of the seatpost. Normally there’s a mark to tell you how much of the seatpost needs to be inserted in the frame, however this isn’t always the case so we’d recommend allowing a minimum of 6 cm.
Zeus Gran Sport Vintage 27.2 mm Seatpost
£50.00
✓ Original part - produced in the 1970s
✓ Suitable for historic cycling events such as L'Eroica
✓ Professionally checked & cleaned
✓ Worldwide shipping
Zeus Gran Sport seatpost, hailing from Spain and in production during the 1970s. Made from aluminium/steel and weighing in at 318 grams. A fine choice for keeping your vintage bike authentic, but also great for any other compatible bike too.
If you're taking part in L'Eroica or a similar vintage event, this is fully compliant - so rest assured, the pre-1987 police won't lock you up for having the wrong seatpost!
The seatpost's been carefully cleaned, thoroughly checked by one of our mechanics and graded as good condition, but do take a good look at the detailed photos so you can see the cosmetic condition before you buy.OVERVIEW
Production Era - 1970s
Country - Spanish
Material - Aluminium/Steel
Weight - 318 g
Stock Code - U-SP90V
TECHNICAL INFO
Seatpost Diameter - 27.2 mm
Length (Centre of Rails to Base) - 215 mm
-
▼SHIPPING, TAXES & RETURNS
-
We've been safely sending orders around the world since 2010. There's a handy shipping calculator on the shopping cart page so you can see the cost of postage as soon as you've added it to your basket. Your order will be carefully packed and sent with tracking & insurance, we despatch most orders within 2-3 days but larger items and orders placed before the weekend can take an extra day or two to process.
We accept returns, please notify us within 14 days and ensure the item arrives back with us no later than 30 days after the order was received.
We don't charge VAT, however, if buying from outside of the UK please remember that there may be import fees to pay directly to the delivery company before receiving the order. Unfortunately we can’t advise on the exact costs as it varies from country to country, so please check your national rates before purchasing.
Zeus Gran Sport Vintage 36h Rear Hub
£55.00
✓ Original hub - produced in the 1970s
✓ Super lightweight for the era - only 209 grams!
✓ Suitable for historic cycling events such as L'Eroica
✓ Professionally checked, cleaned & serviced
✓ Worldwide shipping
Zeus Gran Sport rear hub, hailing from Spain and in production during the 1970s. Made from aluminium/steel and weighing in at 209 grams - incredibly lightweight for a rear hub at that time. A fine choice for keeping your vintage bike authentic, but also great for any other compatible bike too.
If you're taking part in L'Eroica or a similar vintage event, this is fully compliant - so rest assured, the pre-1987 police won't lock you up for having the wrong hub!
The hub's been carefully cleaned, thoroughly serviced by one of our mechanics and graded as good condition, but do take a good look at the detailed photos so you can see the cosmetic condition before you buy.OVERVIEW
Bearing / Race Condition - Good
Production Era - 1970s
Country - Spanish
Material - Aluminium / Steel
Weight - 209 g
Stock Code - U-HU-R43V
TECHNICAL INFO
Spoke Drilling - 36 Hole
Spacing (O.L.D.) - 120 mm
Speed - 5 Speed, 6 Speed
Sprocket Fitting - Screw On (English/ISO: 1.375 x 24 TPI)
-
▼SHIPPING, TAXES & RETURNS
-
We've been safely sending orders around the world since 2010. There's a handy shipping calculator on the shopping cart page so you can see the cost of postage as soon as you've added it to your basket. Your order will be carefully packed and sent with tracking & insurance, we despatch most orders within 2-3 days but larger items and orders placed before the weekend can take an extra day or two to process.
We accept returns, please notify us within 14 days and ensure the item arrives back with us no later than 30 days after the order was received.
We don't charge VAT, however, if buying from outside of the UK please remember that there may be import fees to pay directly to the delivery company before receiving the order. Unfortunately we can’t advise on the exact costs as it varies from country to country, so please check your national rates before purchasing.
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▼HELP SECTION
-
Spoke Drilling - the number of holes for the spokes, your wheel rim needs to match the hub exactly.
Spacing (O.L.D.) - the width of the hub measured at its widest point, from the outside of the locking end nuts (O.L.D. = Over Locknut Dimension), not including the hub axle. This measurement needs to match the inside of your frame's dropouts. Steel frames can be stretched or squeezed a few mm but it's always best to avoid this if possible, aluminium or carbon frames should never be stretched.
Speed - the number of cogs the hub was designed to be used with.
Sprocket Fitting - for cassette hubs this refers to the spline pattern (the shape of the cogs where they slide on to the hub) and this must match the cassette you intend to use. With freewheel hubs it refers to the thread, ISO is the modern standard and is almost exactly the same as older English/British and Italian thread, allowing you to mix and match between these thread types as long as it's not going to be under extreme force, in which case it's best to stick to an exact match. Freewheel hubs with a French thread must be used with a French threaded freewheel.
Zeus Gran Sport Vintage English 118 mm Bottom Bracket
£55.00
✓ Original part - in production from the 1970s to the 1980s
✓ Lightweight for the era - just 262 grams
✓ Suitable for historic cycling events such as L'Eroica
✓ Professionally checked & cleaned
✓ Worldwide shipping
Zeus Gran Sport bottom bracket, hailing from Spain and in production from the 1970s to the 1980s. Made from steel and weighing in at 262 grams - pretty lightweight for a bottom bracket at that time. A fine choice for keeping your vintage bike authentic, but also great for any other compatible bike.
If you're taking part in L'Eroica or a similar vintage event, this is fully compliant - so rest assured, the pre-1987 police won't lock you up for having the wrong bottom bracket!
The bottom bracket's been carefully cleaned, thoroughly checked by one of our mechanics and graded as very good condition, but do take a good look at the detailed photos so you can see the cosmetic condition before you buy.OVERVIEW
Production Era - 1970s & 1980s
Country - Spanish
Material - Steel
Weight - 262 g
Stock Code - U-BB120V
TECHNICAL INFO
Thread Type - English Thread (British/ISO 1.37" x 24 TPI)
Axle Length - 118 mm
Axle Type - Square Taper
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▼SHIPPING, TAXES & RETURNS
-
We've been safely sending orders around the world since 2010. There's a handy shipping calculator on the shopping cart page so you can see the cost of postage as soon as you've added it to your basket. Your order will be carefully packed and sent with tracking & insurance, we despatch most orders within 2-3 days but larger items and orders placed before the weekend can take an extra day or two to process.
We accept returns, please notify us within 14 days and ensure the item arrives back with us no later than 30 days after the order was received.
We don't charge VAT, however, if buying from outside of the UK please remember that there may be import fees to pay directly to the delivery company before receiving the order. Unfortunately we can’t advise on the exact costs as it varies from country to country, so please check your national rates before purchasing.
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▼HELP SECTION
-
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.
Zeus Gran Sport Vintage Italian Thread 118 mm Bottom Bracket
£75.00
✓ Original part - in production from the 1970s to the 1980s
✓ Suitable for historic cycling events such as L'Eroica
✓ Professionally checked & cleaned
✓ Worldwide shipping
Zeus Gran Sport bottom bracket, hailing from Spain and in production from the 1970s to the 1980s. Made from steel and weighing in at 301 grams. A fine choice for keeping your vintage bike authentic, but also great for any other compatible bike too.
If you're taking part in L'Eroica or a similar vintage event, this is fully compliant - so rest assured, the pre-1987 police won't lock you up for having the wrong bottom bracket!
The bottom bracket's been carefully cleaned, thoroughly checked by one of our mechanics and graded as very good condition, but do take a good look at the detailed photos so you can see the cosmetic condition before you buy.OVERVIEW
Production Era - 1970s & 1980s
Country - Spanish
Material - Steel
Weight - 301 g
Stock Code - U-BB82V
TECHNICAL INFO
Thread Type - Italian Thread (ITA 36 mm x 24 TPI)
Axle Length - 118 mm
Axle Type - Square Taper ISO
-
▼SHIPPING, TAXES & RETURNS
-
We've been safely sending orders around the world since 2010. There's a handy shipping calculator on the shopping cart page so you can see the cost of postage as soon as you've added it to your basket. Your order will be carefully packed and sent with tracking & insurance, we despatch most orders within 2-3 days but larger items and orders placed before the weekend can take an extra day or two to process.
We accept returns, please notify us within 14 days and ensure the item arrives back with us no later than 30 days after the order was received.
We don't charge VAT, however, if buying from outside of the UK please remember that there may be import fees to pay directly to the delivery company before receiving the order. Unfortunately we can’t advise on the exact costs as it varies from country to country, so please check your national rates before purchasing.
-
▼HELP SECTION
-
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 just by looking at the shape of the bottom bracket hole in your crankset. The square taper axle came in two variations; JIS which was produced for cranksets made in Asia and ISO for cranksets made in Europe, these taper down to a slightly smaller end than JIS axles. There are a few exceptions such as some Sugino cranksets that required an ISO axle and some older Dura-Ace cranksests which used a shorter 'low profile' variation of the JIS taper. Ofmega/Avocet also had their own variaton of the ISO taper which is not compatible with any other type.
Zoom Adjustable Silver NOS Classic 120 mm 1 1/8" Quill Stem
£40.00
✓ Original part - produced in the 1990s
✓ New old stock! Still unused after all these years
✓ Worldwide shipping
Zoom stem, hailing from China and in production during the 1990s (yet still new & unused after all this time!). Made from aluminium/steel and weighing in at 507 grams. A fine choice for keeping your classic bike authentic, but also great for any other compatible bike.
OVERVIEW
Production Era - 1990s
Country - Chinese
Material - Aluminium / Steel
Weight - 507 g
Stock Code - D-ST178C
*New old stock items may have marks from storage over the years, and as we often have multiples they can vary from piece to piece, but they are always genuine new & unused items.
TECHNICAL INFO
Extension Length (ctc)* - 120 mm
Quill Size - 1 1/8"
Steerer Size (ID) - 25.4 mm (Standard 1 1/8")
Total Shaft Height - 180 mm
Clamp Size - 25.4 mm
*See help section.
-
▼SHIPPING, TAXES & RETURNS
-
We've been safely sending orders around the world since 2010. There's a handy shipping calculator on the shopping cart page so you can see the cost of postage as soon as you've added it to your basket. Your order will be carefully packed and sent with tracking & insurance, we despatch most orders within 2-3 days but larger items and orders placed before the weekend can take an extra day or two to process.
We accept returns, please notify us within 14 days and ensure the item arrives back with us no later than 30 days after the order was received.
We don't charge VAT, however, if buying from outside of the UK please remember that there may be import fees to pay directly to the delivery company before receiving the order. Unfortunately we can’t advise on the exact costs as it varies from country to country, so please check your national rates before purchasing.
-
▼HELP SECTION
-
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 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.
Zoom MTB-110PP NOS Steel Classic 560 mm Flat/Straight Handlebars
£20.00
✓ Original bars - produced in the 2000s
✓ New old stock! Still unused after all these years
✓ Worldwide shipping
Zoom MTB-110PP handlebars, hailing from China and in production during the 2000s. Made from steel and weighing in at 415 grams. A fine choice for keeping your classic bike authentic, but also great for any other compatible bike.
OVERVIEW
Model ID - MTB-110PP
Production Era - 2000s
Country - Chinese
Material - Steel
Weight - 415 g
Stock Code - D-HBF42C
*New old stock items may have marks from storage over the years, and as we often have multiples they can vary from piece to piece, but they are always genuine new & unused items.
TECHNICAL INFO
Width (outside to outside) - 560 mm
Bar Type - Flat/Straight
Clamp Size - 25.4 mm
Grip Diameter - 22.2 mm
-
▼SHIPPING, TAXES & RETURNS
-
We've been safely sending orders around the world since 2010. There's a handy shipping calculator on the shopping cart page so you can see the cost of postage as soon as you've added it to your basket. Your order will be carefully packed and sent with tracking & insurance, we despatch most orders within 2-3 days but larger items and orders placed before the weekend can take an extra day or two to process.
We accept returns, please notify us within 14 days and ensure the item arrives back with us no later than 30 days after the order was received.
We don't charge VAT, however, if buying from outside of the UK please remember that there may be import fees to pay directly to the delivery company before receiving the order. Unfortunately we can’t advise on the exact costs as it varies from country to country, so please check your national rates before purchasing.
-
▼HELP SECTION
-
Width - the total width at its widest point, from end to end, rounded to the nearest cm.
Clamp Size - this should match the internal diameter of your handlebar stem clamp, and should be as close as possible to ensure a good and safe fit.
Grip Diameter - the outside diameter of the area where handlebar grips are fitted, this determines not only what grips will fit but brake levers too so it's important to check if you have a specific setup in mind.
Rise/Drop - we measure this at the end of the bars, from the centre point of the clamp area to the centre of the end. This measurent can change when the bar is rotated so there is a bit of tolerance here, please use this as an approximate measurement only.
Zoom Original Black NOS Classic 120 mm 1 1/8" Quill Stem
£35.00
✓ Original part - produced in the 1990s
✓ New old stock! Still unused after all these years
✓ Lightweight for the era - just 296 grams
✓ Worldwide shipping
Zoom stem, hailing from China and in production during the 1990s (yet still new & unused after all this time!). Made from steel and weighing in at 296 grams - pretty lightweight for a stem at that time. A fine choice for keeping your classic bike authentic, but also great for any other compatible bike.
OVERVIEW
Production Era - 1990s
Country - Chinese
Material - Steel
Weight - 296 g
Stock Code - D-ST173C
*New old stock items may have marks from storage over the years, and as we often have multiples they can vary from piece to piece, but they are always genuine new & unused items.
TECHNICAL INFO
Extension Length (ctc)* - 120 mm
Quill Size - 1 1/8"
Steerer Size (ID) - 25.4 mm (Standard 1 1/8")
Total Shaft Height - 130 mm
Clamp Size - 25.4 mm
*See help section.
-
▼SHIPPING, TAXES & RETURNS
-
We've been safely sending orders around the world since 2010. There's a handy shipping calculator on the shopping cart page so you can see the cost of postage as soon as you've added it to your basket. Your order will be carefully packed and sent with tracking & insurance, we despatch most orders within 2-3 days but larger items and orders placed before the weekend can take an extra day or two to process.
We accept returns, please notify us within 14 days and ensure the item arrives back with us no later than 30 days after the order was received.
We don't charge VAT, however, if buying from outside of the UK please remember that there may be import fees to pay directly to the delivery company before receiving the order. Unfortunately we can’t advise on the exact costs as it varies from country to country, so please check your national rates before purchasing.
-
▼HELP SECTION
-
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 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.