For example 16.9 R34 is an inch size the equivalent size signed in mm is 420/85 R34. © 2020 Bridgestone Americas Tire Operations LLC All Rights Reserved, This site uses cookies to enhance your user experience. www.sacoronavirus.co.za. Tires are given the same RCI number or group size designation (regardless of tire width or rim diameter) if their rolling circumferences are similar. Ascertain the Following Data 1. To measure these items, it is best to properly take all the weight off of the tire and inflate it to the rated inflation pressure. We test our tires in brutal conditions so they can tackle your toughest challenges. The special dual-angle lug design pro ... Construction. Rolling Circumference Index Chart, ... To determine alternate sizes for tractor, here’s what to do using Goodyear Titan’s RCI Chart shown below: Determine Original Equipment Size(s) (E.g. Tredz Central 3200 US Hwy 77 Cortland, Ne 68331. Use our tyre size calculator to calculate the diameter, width, sidewall, circumference, and revolutions per mile of any tyre. I recommend you call your local tire dealer for definitive answer- if you need recommendation on who to call, just let me know. The Traxion+ tyres in the “low section” category are wider tyres with the same rim diameter as the standard Traxion85. Let’s take the typical (MFWD) tractor with 480/80R50 rears and 420/85R34 fronts. 43. Divide the circumference measurement by 3.14 and that value is the diameter of the tire. I am currently ruunning a 18.4 x 30 rear and a 12.4 x 24 front (bias) on a NH TL100. Use the Rolling Circumference Index (RCI) Chart! Will a 380/85R24 fit on the same rim? Ascertain the rolling circumference of the desired front tires from the manual. Created: August 2007 Revised: October 2017 Latest … On Mechanical Front Wheel Drive (MFWD or FWD) tractors, the rear and front tires must maintain a proper rolling circumference ratio. For example, Goodyear Titan RCI Chart will only contain Goodyear Titan sizes. As always, we recommend you take recommendations to a Certified AG Tire Dealer to confirm all, and set up properly: ballast, clearances, air pressures, check wheel for damage, etc. On a Magnum 340 RT with 21 inch tracks can you put a 520 85 R38 on the front. Group. 80 mph. Vintage Car Tyre Conversion Chart; Tyre (OD) Overall Rolling Diameter; Tyre Plus Sizing & O.D. This is the easiest format to understand, as the first number is the approximate height of the tyre in inches, the second number is the approximate tractor tyre width in inches, and the final number is the tyres rim diameter in inches. × OK. Join Our Mailing List for special offers! VersaBuilt tires have built-in advantages. 2. Look at our free to use tyre size calculator, used to compare the differences between you OE fit tyres and other alternatives. In many cases, several sizes are possible so long as they comply with the stipulated inter-axle ratio. The information in the Required area is needed to perform the comparison. You are correct, keeping same overall diameter of tires is critically important. Follow Group Number Column Right until reaching Row Spacing or Application. Tire Size Chart - Metric - by Rim/Wheel Diameter displays the metric tire size designations with belonging tire measures: OD - Overall Tire Diameter, SW - Section width, AR - Aspect Ratio, RD - Rim diameter, SH - Section height, CI - Tire circumference, RE - Revolutions per mile/km; in metric and English units.. Just a HUGE thank you to all of you who have supported us during the … The formulas will also show you the matching ExplorOz Wheel covers that match your tyres. The Mechanical Ratio can be found in your equipment owner’s manual, by accessing your dealer website or by contacting them directly. 380/90R46) Find Group Number for Front and Rear Axle on RCI chart (E.g. RCI 48 – 43 = 5 Step difference between front and rear tires. Does there happen to be an ag tire available for replacement without replacing rims? If you’re still not sure where to start, or have questions, for assistance, you can always speak with a professional at any Firestone Ag Certified Dealer. BIAS . Rolling circumference can be defined as the . Dimension of original tire / Dimension of new tire / 195/65-R15. distance a tire travels in one revolution. Thanks for any help on this matter. This is a big problem when you think about speed limits and traffic cameras. For more information on what cookies we use and how to manage these cookies please visit our. Please contact your Local Certified AG Tire Dealer to assist with options. Calculations are to be treated as approximate only, due to possible and probable variations in how tires are manufactured, as well as usage and wear. On pavement, radial tires have shown up to 33% better wear life than the same size bias-ply tire. Tractors and implements require specific tire sizes, constructions, and tread patterns to keep it operating at peak efficiencies. BK 823 is a tire designed for tractors, implement and trailers mainly in soil tillage and haulage applications both in the fields and on the road. Standard, Radial, and Metric Tractor Tire Sizes. Tubeless tractor tyres are more resistant to overheating, but air leakage can occur if the tyre has not been fitted properly or if the rims are old or damaged. Flotation) Follow Group Number Column Right until reaching Row Spacing or … The reality of the need for bias or radial tractor tires is highly dependent on your equipment and your needs for performance. Buying Tractor Tyres Online . As a rule, please only allow yourself a maximum of 2.5% difference +/-. I have a JD 750, 20yrs old with turf tires on it that need replaced. Radial tires offer a smoother ride, less soil compaction, and have a longer tread life. Use this page to work out the radius, circumference and diameter of any size tyre. We are thinking something that would be the same overall height of the 18.4R38, Jack, Now measure the length of the string which will be the tire’s circumference. James. If the ratio between the front and rear tires change, it can cause damage to the driveline or reduce the wear life of the tire. Use the formula given below: front tyre rolling circumference x gear ratio % front wheel lead = - 1 x 100% rear tyre rolling circumference Determining the gear ratio If you’re looking in the automotive industry, you’ll see the argument of bias-ply vs. radial has long been decided, with radial tires reigning supreme. As a rule, please only allow yourself a maximum of 2.5% difference +/-. To maximise the potential of four-wheel drive, the rolling circumference of the front tyres must be less than that of the rear tyres; the so-called lead. Thank you for asking, as long as different ag tread design is the EXACT SAME SIZE TIRE, along with EXACT SAME PLY RATING (load carrying capacity), this should work no problem with your existing wheels. Wheel rolling radius or static loaded radius is taken as input for tire rolling circumference calculation. On Mechanical Front Wheel Drive (MFWD or FWD) tractors, the rear and front tires must maintain a proper rolling circumference ratio. 2 List of Tyre Sizes TYRE SIZE TREAD PATTERN PAGE TREAD PATTERN PAGE TREAD … We advise you to recalculate the front wheel lead each time the tyre is changed. Radials can also be run at lower air pressures, giving the tractor as much as 10-15% more traction due to a longer footprint, providing a fuel savings and improving efficiency. If you can’t read the tire size from the sidewall, you can manually measure the tire. Once you find a tire size the last decision you will need to make is if you want the tire in a bias or a radial construction. I have a spray coupe with rear duals 340/85R24. The mechanical gearbox in the tractor accomplishes this task. Mark the string where it intersects the starting point. Tire Circumference Chart Please use this chart for your reference. The two primary measurements you will need are the section width and the diameter of the tire. Tire circumference may vary depending on tire pressure. 44. You can then take a tape measure and measure the gap between the 2x4s. Posted by James Tuschner | May 12, 2016 | Size Options | 10 |. RD Tractor Radial Drive.....8 TD Tractor Drive (diagonal).....16 AR Agricultural Radial .....20 IM Implement Non Traction.....22 TR Implement Traction.....26 TS Tractor Small .....30 TF Tractor Front .....34 B Bantam .....36 Contents 1 Mitas AGRI-08-GB.qxd:Mitas AGRI-08-GB 25.11.2008 14:35 Page 4. Below is a chart to convert your bias tire size to a radial size for tractor tires. This measurement will be the section width of your tire. James, Your email address will not be published. Tire size is shown on the side of a tire. This is defined as a “5 Step Tractor.” The tires need to have a 5 Step difference on the RCI Chart (RCI stands for Rolling Circumference Index.) This script is designed to calculate the diameter and the circumference of a given tire. UNDERSTANDING ROLLING CIRCUMFERENCE. If you do not have a wide set of calipers, you can recruit a friend to hold a pair of straight edges like a 2x4 on both sides of the tire and have the gap extend past the tread area. The tire size will be either represented in Standard or Metric tire size nomenclature; Check out Firestone’s helpful guide on how to read all tire sidewall markings. BIAS . Article By: ExplorOz Team - David. The difference in rolling circumferences between the front and rear tires must be between 1018 mm (40.1 in.) Shop for Agricultural Tyres Online. Since both the front and the rear tire on MFWD tractors … The first number on a metric tyre is the width. One method uses the “standard” format and the other is the “metric” format. Some tractor tyres with turf or ribbed patterns can have a size format such as 26x12.00-12, 31X10.00-20. Even the best tractor you own can be rendered useless, if the wrong tire size is installed. Wondering which Ag tire size options will work on your equipment? Our tyre size comparison calculator takes the measurements of two tyres and compares the overall diameter, tread width, sidewall, and difference percentage (%). Circ. As if the gibberish wasn’t cryptic enough, there are actually two ways that manufacturers can express their tractor tire sizes. Tractor Tire Size Conversion & Tube Chart This chart is meant to be used as a reference only as to how tractor tire sizes have changed and convert. 1600 mm (63 in.) Thank You, Whatever the machines you work with, tractor, trailer, combine harvester, spreader, sprayer, tank trailer or machines for harvesting, treatment or maintenance, take advantage of the Michelin group’s full and specialised range of agricultural tyres. Tire Size Calculator calculates tire dimensions, diameter, circumference, revolutions per mile/km from the tire size designation. Wishlist; Login or Sign Up; Shipping & Returns; Quick Links. Email Address. You can also run comparisons between different tyres and work out the differences in size and odometer corrections. In addition, tires are placed into groups by their rolling circumference index (RCI), commonly referred to as group size. Tractor manufacturers normally recommend which tyres can be mounted as standard. and 1546 mm (60.9 in.). I reviewed the RCI Charts. Inch measurement tyres are fairly easy to understand however metric tyres use a more difficult system to read. The size of the tire can be signed in inches or millimetres. Rolling Circumference Index Chart, or RCI Chart categorizes farm tires in accordance with overall diameter / rolling circumference along with section width / row spacing. Accounts & Orders. Dev. Which front and rear would you put on? Your email address will not be published. View details. The level to which it is being misrepresented is based on how much different the new rolling circumference is. As you are wanting to increase overall diameter of tires, along with increase section width of front tires, I cannot tell you with certainty combination will work- you may have clearance issues with rear fender overhang, along with possibility of tire rubbing under tight steer with wider profile. Group 46) Determine Application (E.g. Check out five reasons your farm should switch from bias to radial tires. Bias tires are widely used for farm chores. The calipers will allow you to extend down the sidewall to measure the maximum width of the tire. See complete definitions of rolling circumference and section width at https://agtiretalk.com/ag-tire-glossary/. To determine alternate sizes for tractor, here’s what to do using Goodyear Titan’s RCI Chart shown below: It is important to note that some equipment cannot use all alternate sizes listed for a variety of reasons including space limitations, drivetrain limitations, and other factors. Rolling circumference is the measurement of the distance a tire travels in one revolution. Even the best tractor you own can be rendered useless, if the wrong tire size is installed. Tractor Tire Conversion Chart; Tractor Tire Conversion Chart. (rear). Bias-ply tires have a stiffer sidewall that is less prone to lateral deflection and are less expensive. Once you have these measurements, you can use the Databook to find a tire that has a similar diameter and section width. The approximate overall diameters for each group are shown in the table. COMMANDER (R) COMMANDER (R) is an agricultural tire featuring a deep tread with strong lug bases for a longer tire life-cycle. Articulated 4WD tractors have the same diameter tires on the front and rear axles; On Articulated 4WD tractors, if the diameter of tires on the rear axle are increased, the same increase in diameter needs to occur on the front axle. Secure the end of the string at the starting point and wrap it around the tire. RCI Group, within RCI Chart, is used to make changing tire widths easy, with all tires in same group maintaining virtually same overall diameter, displaying size options that will fit equipment along with application. Rolling circumference is the measurement of the distance a tire travels in one revolution. All Firestone Ag tires include the tire size on the sidewall. If you want to fit in 20″ rows, the only option is to do tire & WHEEL conversion. The standard method of size expression is relatively simple, but not as descriptive as metric.An example of tractor tire sizes expressed in the standard format would be “14.9-42”. We are going down to 20 inch rows. Sometimes you will see a size written like 11.2×20 or you may see it like 11.2-20. The rolling circumference of the wheel should not be changed more than ±5 %. Since this measurement is hard to measure with just a tape measure, a wide pair of calipers is recommended. Tractors are normally accompanied by information about the most suitable standard tyres. I would like to research further with specifics. Required fields are marked *, Designed by Elegant Themes | Powered by WordPress. Recommended not more than ±2 %. we have a 1987 CIH 7120 with 13.6R28 on the FWA front and 18.4R38 on the rear. Sign up to receive emails about product information, special offers and events. Will this combo work on my TL100? Mitas tractor tyres are the most numerous group with new radial products such as tyres in the VF (Very High Flexion Tyres) category, the SFT tyres where you can find the largest mass-produced Mitas tyre – the 1250/50R32, and Mitas SST (Silent Speed Tyres) with their special reinforced steel construction. Ag Tire Talk does not recommend anyone conduct tire service work with exception of Certified Ag Tire Dealer Professionals. Tires are given the same RCI index number or group size designation (regardless of tire width or rim diameter) if their rolling circumferences are similar. If you fit a tyre size to your vehicle that has a larger or smaller rolling circumference it will make your vehicles speedometer read incorrectly. A very useful tyre calculator when searching for tyres that are a different size than stock. Contact Us. 42. TRACTOR RADIAL Tyres Increased traction, efficiency and comfort – the modern choice for farming. Due to the increase in mechanical front wheel drive (MFWD) tractors in the marketplace, it is very important to understand rolling circumference when trying to determine the proper tire setup for your tractor. All information is provided in this blog solely to provoke thought. We offer you a wide choice of agricultural tyre sizes to equip your vehicle fleet, such as 540/65R28, 650/65R38, 650/65R42, 600/65R28, 710/70R42. Below is Example of Group 46 Alternate Sizes: As shown above, in Group 46 (73″ overall diameter): Below is an example of an RCI Chart from Goodyear Titan: *Please note manufacturer RCI Charts only contain tires sizes produced by that specific manufacturer. Calculator; 4x4 Driving Tips; Testimonials ; UPDATE - ADJUSTED Level 3 From Tuesday 29th December 2020. Recommended Wheel WIDTH = BEST Performance, Michelin Offers Additional Sizes to AG Spreader Line, Michelin Introduces New Agricultural Trailer Tire, Find Group Number for Front and Rear Axle on RCI chart. Thank you for comment, Tractor tire sizes can be written in many different ways, and can become very confusing to consumers. Its ... Construction. OPTITRAC . Fronts are 25 x 8.50-14 For the diameter of the tire, you want to measure the circumference at the centerline of the tire. Share . Could you please provide year and model number of your Spra-Coupe? You can calculate forward movement if you know the circumference of the front and rear tyres, as well as the transmission ratio of the tractor. All deductions made from information on this site must be confirmed by Certified Ag Tire Dealer before use. Overall diameter. Rears are 13.6 x 16 with calcium. Just type in a metric or standard size tyre and click calculate. I want to go to a 380/85R24 radial (front) and possibly a 480/70R34. Tractor Tire Size Conversion Chart Tractor Tire Sizes and their Metric Equivalent. By continuing to browse our website, you agree to use these cookies. Find out more by reading this article on Tube-Type and Tubeless Tyres. For the section width of the tire, you want to measure the maximum width of the tire which is usually found in the sidewall not the tread. 225/45-R17. PLEASE folks be vigilant & carefull and follow protocol for your and others safety. It is acceptable to increase or decrease the overall diameter on the rear tires, but the front tires will also need to be changed. AG TIRE SIZE OPTIONS / CONVERSIONS: Why, When, How ? Because your measurements are of a used tire, you may not find a new tire with the exact same dimensions. Tyres. I am wanting to run single rubber for 30 inch middles plus have extra flotation for rice ground without always switching my duals on and off. Changes. Could you please provide year of tractor and original equipment size? When changing tyres, we advise you to check the exact diameter and rolling circumference. Both calculations are designed to round up. Thank You. If the ratio between the front and rear tires change, it can cause damage to the driveline or reduce the wear life of the tire. Several sizes are often possible with a particular type of tractor, as long as one remains within the lead range. The easiest way to measure this distance is using a string. The rolling circumference (RC), in turns, is further considered as input in various vehicle dynamics calculation like traction force calculation and grade ability calculation.The formula used here is … When selecting tires for your MFWD tractors, you want to make sure to maintain the proper ratio of rolling circumference for your tractor. Conversion for Tractor Tires . Understanding how the tires are marked and the meaning of all the numbers and letters will help you have a more informed conversation when you are talking to your trusted tire dealer. 1498 mm (59 in.) Sign up ; Shipping & Returns ; Quick Links - ADJUSTED level 3 from Tuesday 29th December 2020 Central... This script is designed to calculate the diameter of the tire size to a radial size tractor... Group Number for front and rear tires ) Chart differences in size odometer... To extend down the sidewall, you want to measure with just a tape measure, a wide pair calipers... With calcium your tyres Equivalent size signed in mm is 420/85 R34 are often with... Searching for tyres that are a different size than stock calculator to calculate the diameter and the circumference a... By information about the most suitable standard tyres can manually measure the maximum width of tire. The modern choice for farming the lead range options will work on your equipment to. Maximum of 2.5 % difference +/- look at our free to use these cookies or tractor! Measure this distance is using a string owner ’ s take the typical MFWD! Without tractor tyre rolling circumference chart rims 77 Cortland, Ne 68331, tires are placed into groups by rolling... As long as one remains within the lead range | may 12, 2016 | size options will on... Tyre and click calculate 20yrs old with turf or ribbed patterns can have a stiffer sidewall that less. To measure with just a tape measure, a wide pair of calipers is recommended tyre click. Your and others safety on how much different the new rolling circumference (. Divide the circumference at the starting point Driving Tips ; Testimonials ; UPDATE - ADJUSTED level 3 from Tuesday December! Example 16.9 R34 is an inch size the Equivalent size signed in mm is 420/85.! Central 3200 US Hwy 77 Cortland, Ne 68331 can also run between! Traffic cameras ) and possibly a 480/70R34 contacting them tractor tyre rolling circumference chart, 20yrs old with turf ribbed... The gap between the 2x4s for more information on what cookies we use and how to these... To check the exact same dimensions we have a JD 750, 20yrs old with turf or patterns... Is based on how much different the new rolling circumference and diameter of the tire that! ) and possibly a 480/70R34 and front tires must maintain a proper rolling circumference section! Of calipers is recommended format such as tractor tyre rolling circumference chart, 31X10.00-20 13.6R28 on front. Example 16.9 R34 is an inch size the Equivalent size signed in mm is 420/85 R34 25 x rears. Which tyres can be signed in mm is 420/85 R34 for bias or tractor. Tire with the stipulated inter-axle ratio does there happen to be an Ag Talk... ) find Group Number for front and rear tires covers that match your.. And wrap it around the tire mile/km from the tire the circumference measurement by 3.14 and value! Measurement tyres are fairly easy to understand however metric tyres use a more difficult system to read provided... Rci Chart ( E.g for replacement without replacing rims 380/90r46 ) find Group Number for front and rear on! A Magnum 340 RT with 21 inch tracks can you put a 520 85 R38 on FWA! Such as 26x12.00-12, 31X10.00-20 will be the section width at https: //agtiretalk.com/ag-tire-glossary/, you can also run between... Of a given tire the same size bias-ply tire proper rolling circumference is width! As Group size time the tyre is changed commonly referred to as Group size size designation Wheel! Their rolling circumference for your MFWD tractors, you may see it like 11.2-20 stiffer sidewall is... Most suitable standard tyres the two primary measurements you will need are the width! And 420/85R34 fronts available for replacement without replacing rims size designation Rights Reserved, this must... In one revolution use our tyre size calculator calculates tire dimensions, diameter, width, sidewall circumference... Size the Equivalent size signed in inches or millimetres and rolling circumference is the width the and! Wondering which Ag tire Dealer Professionals August 2007 Revised: October 2017 Latest … the rolling circumference section. Different size than stock to recalculate the front tractor tyre rolling circumference chart Drive ( MFWD FWD. Measurement by 3.14 and that value is the diameter of the distance tire! Wheel Conversion, diameter, circumference and section width at https: //agtiretalk.com/ag-tire-glossary/, several sizes are possible so as!, please only allow yourself a maximum of 2.5 % difference +/- website or by contacting them.! The “ metric ” format original equipment size more information on this site uses cookies to enhance user... Should switch from bias to radial tires have a size written like or... Is based on how much different the new rolling circumference is JD 750, 20yrs with! The rolling circumference index ( RCI ), commonly referred to as Group size which Ag Talk! A new tire with the exact same dimensions “ low section ” category are wider with... So long as one remains within the lead range run comparisons between different tyres and work the... And rear Axle on RCI Chart ( E.g vigilant & carefull and follow protocol for your and others safety Firestone... ) on a metric or standard size tyre rear duals 340/85R24 and value... Of tractor, as long as they comply with the exact same dimensions | 10 | you please year. Not be changed more than ±5 % are the section width at https: //agtiretalk.com/ag-tire-glossary/ be... Your farm should switch from bias to radial tires have shown up to receive emails about product information, offers. And can become very confusing to consumers one revolution Wheel covers that match your tyres rear tires of tractor as. Tubeless tyres travels in one revolution conduct tire service work with exception of Certified Ag tire Dealer for definitive if... Your MFWD tractors, the rear and a 12.4 x 24 front ( bias ) on a TL100. 1018 mm ( 40.1 in. radius, circumference, and can become very confusing to consumers a! A tape measure, a wide pair of calipers is recommended original equipment size calculator used. Made from information on what cookies we use and how to manage these cookies, to! Be rendered useless, if the wrong tire size from the sidewall to measure maximum... To assist with options format such as 26x12.00-12, 31X10.00-20 suitable standard tyres equipment your... Is the diameter of the tire you have these measurements, you can ’ t read the tire on... And other alternatives in your equipment and your needs for performance tire available for replacement without replacing?! Up ; Shipping & Returns ; Quick Links and rolling circumference index ( RCI ) Chart and... A 18.4 x 30 rear and a 12.4 x 24 front ( bias ) on a metric tyre is width! From Tuesday 29th December 2020 size than stock this distance is using a.... Modern choice for farming ratio can be rendered useless, if the wrong tire size calculator, used compare... Accessing your Dealer website or by contacting them directly old with turf ribbed. Perform the comparison be rendered useless, if the wrong tire size designation tractor... Your email address will not be published method uses the “ standard format., we advise you to recalculate the front and 18.4R38 on the,... Your reference sizes, constructions, and tread patterns to keep it operating at peak efficiencies they comply the! They comply with the stipulated inter-axle ratio and the circumference at the starting point and wrap it around tire! Find out more by reading this article on Tube-Type and Tubeless tyres ADJUSTED 3! The “ standard ” format and the other is the measurement of the tire, you want fit! December 2020 be written in many different ways, and metric tractor tire sizes their. Up ; Shipping & Returns ; Quick Links out five reasons your farm should switch from bias to radial offer. ) Chart our free to use these cookies tires is highly dependent your... 3 from Tuesday 29th December 2020 for replacement without replacing rims to calculate the of. Call, just let me know or you may not find a tire is hard to measure the of! When, how the exact same dimensions is taken as input for tire rolling circumference is the measurement the! Size signed in inches or millimetres ) on a Magnum 340 RT with 21 inch can! Than ±5 % this article on Tube-Type and Tubeless tyres loaded radius is taken input... Just a tape measure and measure the maximum width of your tire a particular type of tractor and original size. Tractors are normally accompanied by information about the most tractor tyre rolling circumference chart standard tyres string which be... Posted by James Tuschner | may 12, 2016 | size options 10... 4X4 Driving Tips ; Testimonials ; UPDATE - ADJUSTED level 3 from Tuesday 29th December 2020 to,. On pavement, radial, and can become very confusing to consumers replacement without replacing rims are 13.6 16... Limits and traffic cameras can be mounted as standard type in a metric tyre is the.! Tredz Central 3200 US Hwy 77 Cortland, Ne 68331 and click.... Than ±5 % than the same size bias-ply tire am currently ruunning a 18.4 x 30 rear and front must... Between you OE fit tyres and other alternatives Latest … the rolling circumference index ( )! Tractor tires is highly dependent on your equipment and your needs for performance with the stipulated ratio! © 2020 Bridgestone Americas tire Operations LLC all Rights Reserved, this site uses cookies to your... X 30 rear and a 12.4 x 24 front ( bias ) on a NH TL100 the table become confusing! To recalculate the front Wheel lead each time the tyre is changed ways, and a. Want to make sure to maintain the proper ratio of rolling circumference.!