Valve extenders come in a range of sizes, types and even colours. These ones simply screw over the top of an open Presta valve, but you can also get ones that allow you to place the valve core at the top. Simon Bromley/Immediate Media On the other hand, they’re much more fragile and more awkward to fit as they’re floppier than butyl tubes. The following sizes are common for mountain bike tyres, regardless of whether your bike has 26in, 27.5in (650b) or 29in wheels. The Dunlop valve, also known as a Woods is a variation of pneumatic valve that is rarely used on modern bikes. However they were once popular. They look like a cross between the two valves, with a wider lower section, like the Schrader, then a collar and a narrow top section, like the Presta. As the rim drilling is the same for both Woods and Schrader, it is easy to replace the older tubes with the more modern variety. How can I choose the right valve length? This is the traditional method for marking car and van tyres, so is also used quite often for trailer and caravan tyres. The first part is the width of the tyre in mm, the second part, if present, is the height of the sidewall expressed as a percentage of the width, and the third part is the rim diameter in inches. If there is no percentage indication in the tyre size, the tyre sidewall height is taken to be 80% of the width. You may sometimes see a tyre with the 80% in the size eg. 155/80-13. The 'R'. when present within the size, means the tyre is of radial construction.

There is some overlap in sizes between 650b gravel and mountain bike tyres, but gravel tyres are usually sold in metric sizes as listed above. Straight Rubber Valves - The valve is made of rubber so is inexpensive & durable. The TR13 valve is the most common, used on car, trailer, quads, lawn mowers & some smaller agri machinery. It has a thin and straight valve stem. The TR15 has a wider / fatter valve stem so is used in wheels that have a larger valve hole, typicallylarger agri machinery or landrovers. The load index and speed index is gradually replacing the PR marking for tyres. The load index is given by a number between zero and 159 in our chart, but can be much higher. The speed index is given by a letter (or letter and number in the case of 'A' speed rating) between A and Z. Typical examples for our type of tyres would be 68M, 55N or 38F. Any ATV tyres we list with this marking will also be 'E' marked and fully road legal. Contrary to the PR marking, the LI and SI give unambiguous and comparable information on the load capacity which can be drawn from the tables below; Speed symbol It is becoming more common for ATV and turf tyres to be marked up in this manner. They are usually dual marked with their traditional inch dimensions, but if you are handy with a calculator, it's possible to convert from one to the other. For example, a 255/60-10 ATV tyre would be 255mm wide, have a 153mm sidewall height and fit a 10" rim. Converting these dimensions to inches would give us 10" width, 6" sidewall height and 22" (10" rim plus two lots of 6" high sidewalls) overall height. In traditional ATV tyre size marking, this would become a 22x10.00-10.Home> Buying Guide: Inner Tubes Our Guide to Buying: Inner Tubes What are Cycling Inner Tubes? In a nutshell If you have carbon rims on a bike with rim brakes, you also need to be careful not to drag your brakes on long descents because overheating can cause latex tubes to fail. Some wheel makers recommend against using latex tubes with their rims. If your wheels are even deeper than the longest valve you can find, you can buy valve extenders to add length to your valve. There’s a range of lengths available: Zipp for example makes extenders from 27mm up to 98mm long.

This method is widely used on turf and ATV tyres and is probably the easiest to understand. The first part is the overall height (from the ground to the top of the tyre) of the tyre in inches, the second part is the width of the tyre in inches, and the third part is the rim diameter in inches. There are several methods for giving the size of tyres, with measurements sometimes in inches, sometimes in millimetres, sometim es in both! To help you understand a little better, we have examples and explanations of each method below, from which you should hopefully be able to recognise your own size markings.Butyl rubber is the industry standard for common replacement inner tubes, offering a relatively cheap and readily available replacement product. Butyl is strong and resistant, and there are lightweight versions for those looking for weight savings - the Specialized Turbo range and Continental Supersonic tubes are popular versions. What are the differences between Latex and Butyl rubber tubes? You must make sure you replace your inner tubes with a tube that is the right size according to the diameter and width for your tyre. The size is almost always written somewhere on the sidewall of the tyre. Inner tubes typically state a wheel diameter and width range for which they will work, e.g. 26 x 1.95-2.125", indicating that the tube is intended to fit a 26 inch tyre with a width of between 1.95 inches and 2.125 inches. A 260x85 tyre would be 260mm high and 85mm wide. Converting these dimensions to inches gives us a tyre 10" high, 3" wide on a 4" rim. The modern equivalent size would be a 3.00-4. Inner tubes are normally made of butyl rubber or Latex, they sit inside your tyre and are inflated with a pump, they sometimes puncture but are easily replaced. Inner tubes are simple but essential – unless you’re riding with tubeless tyres, you’ll always need an inner tube. Carrying spares is always a good idea, even if you are running tubeless, as a large slash or hole will not seal easily.