Gear Ratio Tire Size Calculator

Try various combinations to come up with the best combination of gear ratio and tire size for your vehicle. com Calculate the theoretical 1/8 Mile ET, 1/4 Mile ET, 1/4 Mile Top End Speed, and Ideal 1/4 Mile Gear Ratio for a given application based on the Vehicle Weight (in pounds), Vehicle Horsepower (at the flywheel), RPM through lights (finish line), and Tire Diameter (Height) in Inches. Instructions. You can now save bikes to the database. Enter the maximum potential safe engine RPM. The ratio calculator performs two types of operations: Solve ratios for the missing value when comparing ratios or proportions. We offer a wide variety of quality tires to fit your vehicle and budget. The results will then be: Automatic transmission in Drive; Automatic transmission in Overdrive. 07 was a horrible gear ratio, even for stock tires. Drive Gear Teeth - The Number of teeth for the transmission; Rear End - Rear Gear Ratio (3. The input here is for custom "Final Drive", "1st Gear Ratio", and "1st Gear Top Speed". Once completed, this change immediately alters vehicle speed at a given rpm, rpm at a given speed, and effective gear ratio, which in turn affect both acceleration and fuel economy. This gives me decent fuel efficiency at highway speeds, and enough low end power to throttle through difficult obstacles. See my Free Android Drag Racing Calculator App in the Google Play Store. Its come time for me to rep. The Go-Kart Racing Web Site for the racers of go-karts and their families in the Pacific North West. Bigger tires can help you crawl up those slick rocks, look cool, and rob you of power. The stock 93 RX-7 tires were 225/50/16 (225mm section width, 50% aspect ratio, 16 inch wheel). But the weight isn't the same distance out. We offer a wide range of parts for all years of the Mazda MX-5 Miata. The tire size used - "Tire Size" I have included some primary drives kits by Malossi and Polini. Converting from metric tire size to the more common inches used in those larger 4-wheeling tires can be handy. The bigger the aspect ratio, the bigger the tire's sidewall will be. The gearing formula below relies on the use of the Honda or Deco Gear Ratio Chart. An Easy Way to Compare Ratios Gear inches give you a way to calculate and compare gear ratios. About BoostTown. Gear ratio is calculated as the size (number of teeth) of the front chain-ring divided by the size (number of teeth) of the rear cog. Now noone should need to remove their diff cover, unless you're just wanting to do a differential oil change, to calculate your gear ratio. (mm)" boxes. 38's without using custom axles under the. com Calculate the theoretical 1/8 Mile ET, 1/4 Mile ET, 1/4 Mile Top End Speed, and Ideal 1/4 Mile Gear Ratio for a given application based on the Vehicle Weight (in pounds), Vehicle Horsepower (at the flywheel), RPM through lights (finish line), and Tire Diameter (Height) in Inches. Enter your tire size Tire diameter may vary slightly depending on the manufacturer. 55 gear combination. This chart applies to all Ford non-overdirve transmissions, manual and automatic. Try various combinations to come up with the best combination of gear ratio and tire size for your vehicle. Dennys Driveshafts Speed Calculator helps you to set up your street rod or race car driveline It's a great tool to determine the proper tire diameter rear end gear ratio and transmission ratio as compared to actual engine rpm and road speed Use it to fi. Anyway, when I plugged the tires that I was looking at into the spreadsheet, the first ratio that I looked at was. With several distributions most gears and parts are only a day or two away. Gearing is what you are buying when you purchase a Gear Vendors Under/Overdrive. Once you have chosen a specific ratio apply your tire correction factor and then use the following formula to determine the drive-out sprocket to use: Drive-out Sprocket teeth = (Big sprocket teeth * D) divided by (desired gear ratio. Remit to 765 S. More than one stages of pulley speeds can be calculated in a (compound drive system). 10 gear ratio. Divide the number of teeth on each "driven" gear by the number of teeth on the "drive" gear for each interlocking set of gears to calculate the intermediate gear ratios. The gear ratio will converge as the clutch engages. Redlines of 6500 and 7000rpm are listed for comparison. 10s in my truck with 30. This page is done using JavaScript and thus should be compatible with Netscape 3. no need to enter anything in '6th' gear for a car with only 5 speeds). What is the tire size you plan to use? (Example: 255/60/15) If you don't know the tire size, do you know the diameter? What is the axle ratio? Do you know the tooth count of the speedometer drive gear in the transmission? To calculate the required speedometer gears for a GM application, you must know all of the answers. In the forum you will find an informative tech area, a place for Member’s journals, Vendors with special Members pricing, and more!. @1 Wild R/T asked us to host this really cool Tire Size and RPM / Rear End Gear calculator because the site it was on has went away. You can try various combinations to come up with an appropriate combination of ring and pinion gear ratio and tire diameter for your vehicle. in this case the ratio is 2 to 1. This calculator is a useful tool that will do the math to help you figure out the gears that are needed to make your speedometer work correctly. Help I'm looking to figure out the best gear ratios to use on my baja build. Enter the tire size diameter and the target vehicle speed in MPH. 0 Explorer as they never put it in the. the most common i believe is the 3. See my Free Android Drag Racing Calculator App in the Google Play Store. Below I’ve outlined a gear ratio chart that cross compares tire size to gear ratio for the ideal RPM. If the wheel / tire upgrade is done with Mr. 8 3L73 would be an 8. Colors group similar values. Gear Ratio Calculation Basics. Return to above. is one better than the other for a street performance application? any help is appreciated, thanx. To calculate your speedometer difference enter the information for the old tire size, new tire size, old gear ratio, new gear ratio and speed reading. Note that neither of these are equal to the gear ratio for the entire train, 4. Vehicle Speed Calculator Interactively determine your vehicle’s speed in any gear and any engine RPM for best performance. 54 gear worked fine towing a relatively light 8,000 lb. If you wanted to swap out gears to match the tire change, you'd start with a calcluation like this: Old Gear Ratio × New Tire Size ÷ Old Tire Size = New Gear Ratio. 68 gear in the rear now, so that makes my new finale 6. 12 X 38" = 4. 56 gears would be ideal for 35s. Be sure to check the radio box next to the method you want to use. A taller/larger tire is going to need more gear then a stock size F150 tire. 11 gear ratio, and 112 mph, it tells me the RPM is 5123 for an auto trans. Gear Ratio and Tire Size Chart NEXT PAGE This gear ratio and tire diameter chart is meant to give you an approximation of ideal RPMs at highway speed (65 mph) for three situations: fuel economy, every day driving and increased towing power. You can use this Spreadsheet to change the Gear ratio and tire size on your Cummins powered Truck You will see the typical peak power RPMS in green on the chart. It can affect things like shift points in. Revolutions Per Mile Of Your Intended Tire (check with your tire manufacturer!) Derek Drew's "How To Select Gear Ratios For VW Syncro (T3, Transporter, Vanagon) 1996-1992" Instructions: To use this chart look up the revolutions per mile given to you by your tire manufacturer at a given miles per hour. For maximum performance with less converter slip at the lockup point, your converter's stall speed should stall close to these figures. This calculator can give you a good idea of max speed differences using different tire sizes, different gear ratios, or setups that rev a little different. Don Cook saved to New Tire Size / Gear Ratio. Now that you know that 28-inch tall tires reduce your final drive ratio, you can calculate the gearing need to match the performance of your original 26-inch tire/3. Calculate MPH, Use the chart to determine the RPM drop for each gear at speed. This calculator determines the top speed of the vehicle with no margin for mechanical, rolling, or wind resistance. 29 tire dia and 3. Gear inches is used mostly for comparing one drive train ratio to another and has little physical basis on a bicycle with derailleur gears. Gear Inch Ratio Chart For 28 Inch Bicycle Wheel The gear inch ratio for bicycles is defined as: Inch ratio = wheel diameter * (front cog teeth / rear cog teeth) Or putting it another way it is the diameter that a Penny Farthing wheel would need to be to produce the same gear ratio. Total gear ratio of the transmission. For example a tire that is marked 205/65 R16 has a tread width of 205, a profile of 65, and a wheel size of 16". Enter the tire size diameter and the target vehicle speed in MPH. Gear Ratio is the ratio of revolutions of the cranks to revolutions of the rear wheel. Tire size calculator compares diameter, width, circumference and speedometer differences for any two tire sizes. This calculator assumes you know the vehicle's transmission ratio. Simple calculation, but saves one from breaking out the calculator. GM Gear End Gear Ratio Codes. Gear Ratio/Tire Size Calculator By admin - August 2, 2004 HELP with a gear selector issue in my '74 F100. Rear End Axle Ratio (ie 3. The constant "1,000" is used since it is the RPM of the Thunderbird SC speedometer at 60 MPH. 10 ratio is so rare on dealer's lots? Tow rating is drastically reduced with the standard 3. gear ratio for gear 2/gear ratio for gear 1 For my bicycle the ratio of gear 2 to gear 1 is 1. (Some vehicles have what is known as a “staggered fitment" -- different-sized tires on the front and rear axles. 44/16 gear ratio with 20x1. ) in Inches. com for the tire size calculator there as it has sizes in inches as well as metric ratings. 75 inch tire to a 25 inch tire. Backing out the gear ratio gives C = Dx(B/F) = 108x(13/52) = 27 inches as the diameter of your tire. Click on Calculate. Easily find parts for ring and pinion gears, differentials, axle shafts, manual transmission parts, and transfer case parts, using our easy eCatalog. This will give an approximation of your tire diameter and rollout. 29 tire dia and 3. If you don't need a calculator, and just want to see a standard BMX gear chart then click here. That is the current standard for most modern automobile speedometers. If you have a truck, you can go 2 inches taller than the factory size most of the time. This may be a bit inaccurate for CVT driven scooters. Simple calculation, but saves one from breaking out the calculator. Here's and example of how it will be listed and what each part means: For a car with 225/50VR16 tires:. Calculate follower revolutions. rpm / speed / gear ratio calculator. Standard V8 Rear Wheel Drive Applications (1999 to Current) Insert your new tire and gear in the columns on the right. 5 tire width) and a 30 / 11 speed cassette to see where we have overlap or similar gears. • RPM Calculator: Determine what RPM your engine will run based on gear ratio, tire size, transmission and MPH. Tire size, gear ratio, mph and rpm weave an intricate pattern of performance. *** above also offers several ratio adapters. Gear Inches are based on the old high-wheel bicycles. Transmission Gear Calculator v2. 00) and the tire diameter, ground to top of tire as mounted. See the bottom for tire sizing tips, real world vs. To find out what the final gear ratio is, you must multiply the trans ratio by the rearend ratio. Custom tubular suspension systems with coil overs and rack and pinion steering. See effect on RPM in Gear/Sprocket matrix when changing sprockets. But there are a variety of ways to look at gearing and they all have different meanings. The gear ratio on your mini bike or go kart is the ratio between the number of teeth on the clutch, and the number of teeth on the drive axle sprocket. Using bigger diameter wheels/tires with stock ratios will cause more wear and tear on clutch, driveline and engine. Enter the motor pulley size in inches. the most common i believe is the 3. The formula to find the gear inches for your bike is simple. tire radius, tire diameter, rim diameter = inches: gear ratio = if ring and pinion ratio is 4. 12 by your tire diameter. Online motorcycle speed calculator with bike presets for gearing, sprockets, ratio, tyres, chain, RPM etc. Tire Size Calculator: Instructions: Enter the tire information found on the sidewall of your tire. Aspect ratio expresses the height to width ratio as a percent. Using This Pulley and Belt Size Calculator. ) Tire Height - In Inches, Use The Gear Calculator or Tire Size Calculator Speedo Revs/Mile - Number of RPM the speedometer needs to turn at 60mph You can hit the SAMPLE button to see how some typical calculations will look. The tires caused my speedometer to offset by almost 18%. Metric Tire Sizes. Using bigger diameter wheels/tires with stock ratios will cause more wear and tear on clutch, driveline and engine. Note: The circumference of the tire is computed for an ideal circle for the given tire dimensions. If you go from a 25" tire to a 32" tire you would need a reduction of about 28%. GEAR INCHES Somewhat more accurate is something called Gear Inch, which combines gear ratio with wheel diameter (this is overall diameter, including the inflated tire) to calculate how far your bike will travel for one revolution of the crank. In MFWD tractors, both the front and rear tires do the work. Vehicle speeds represented by this calculator are theoretical. 00) and the tire diameter, ground to top of tire as mounted. One way to compensate for this is to swap out your differential gears. We offer a wide variety of quality tires to fit your vehicle and budget. Bicycle gear size and cadence/speed calculator. Gear Ratio and Tire Size Chart NEXT PAGE This gear ratio and tire diameter chart is meant to give you an approximation of ideal RPMs at highway speed (65 mph) for three situations: fuel economy, every day driving and increased towing power. (External Link). It can affect things like shift points in. The gear ratio on your mini bike or go kart is the ratio between the number of teeth on the clutch, and the number of teeth on the drive axle sprocket. 32 posts Here's a really useful online calculator to see how tire size affects speedometer readings. This calculator determines the top speed of the vehicle with no margin for mechanical, rolling, or wind resistance. GM/CHEVROLET FINAL DRIVE RATIOS It is the gear under your seat that counts. Speedometer Gear Chart 200-4R. Find new Gear Ratio with new tire size. When i put the new tire size in and same gear ratio, the multiplier adjusts itself to the difference, then when i save it , it displays the incorrect tire size. For example a tire that is marked 205/65 R16 has a tread width of 205, a profile of 65, and a wheel size of 16". 55 gear combination. I've spend a bunch of time trying to WAG (wild ass guess) my actual MPH when going down the road. A change in gear ratio equal to our example above represents a 150 rpm difference at 6,000 rpm. com; How to use the Gear Calculator V1. Follow Us On Twitter. 75 inch tire to a 25 inch tire. If you go from a 25" tire to a 32" tire you would need a reduction of about 28%. When ever you change tire size from the original size to another there will be a direct effect on power and drivability. Honda Transmission Gear Ratio Calculator. The spinning weight is now half size. Now lets say we have two gears where the drive gear is half the size of the driven gear. Divide the number of teeth on each "driven" gear by the number of teeth on the "drive" gear for each interlocking set of gears to calculate the intermediate gear ratios. TIRE SIZE CHANGE CALCULATOR. That’s why I run a 4. Gear Ratio Gear ratio is simply the ratio of the chain ring size to the rear sprocket size. Place your corresponding numbers into the fields below to calculate your tire height. The left side of the calculator requires all three entries. Try this handy custom calculator. I'll calculate the best chainring/cog combinations and skid patches for your speed and cadence and what your speed will be at various cadences. Speed vs RPM Graph If you have any questions, please don't hesitate to Contact Us. Calculate Engine Size in Cubic Inches and CC's Calculate CI (Engine Size) from Bore, Stroke, and Number of cylinders This Calculator only works when JavaScript is enabled in your browser. The yellow fields are cells where I input data from the car (tire size, final drive ratio, gear ratios 1-5) and the rest is created mathematically in the spreadsheet. The gear ratio expresses the ratio of the output torque to the input torque. Load index (LI) - A uniform method to report the load-carrying capacity of a tire. You can use my Gear Ratio Calculator to see how transmission gear ratios, final drive. The link above helps calculate tire size to gear ratio and what RPM range you will be in at speed. All orders include order tracking. When ever you change tire size from the original size to another there will be a direct effect on power and drivability. To calculate the torque, you just multiply the force by the distance from the center. Learn how to make your slot cars faster and run better on various tracks with this gear ratio chart. Unless driven gears with more than 45 teeth and / or drive gears with fewer than 15 teeth become available, it will be impossible without using a ratio adapter to have an accurate speedometer with rear end gear ratios lower (higher numerically) than 4. The dimensions for the selected tire size will be presented in the table below the calculator. 08 rear end ratio just to make up for the loss of the 700R4's. Splits: The "Split" is the ratio of this gear to the previous gear. Your engine will have to strain harder to get the wheels rolling at the start. 6) Now, multiply tire RPM (672. bicycle bike gear ratio inch speed cadence meters of development calculator using javascript for road track cyclocross and fixie Bicycle gear size and cadence. the relationship between engine speed (rpm) and road speed (mph) is determined by the characteristics of the drivetrain, from the crankshaft to the tire contact patch. All you need is a jack, some jackstands, and knowing how to count helps too. One of the most common places where the hobbyist must grapple with gear ratios is the case of a lathe that uses change gears to cut various threads (as opposed to a lathe equipped with a quick change gear box). i will check later. From experience and friends it seems that 4. Then, multiply that by the axle ratio. Use our gear ratio calculator to find the effective gear ratio your vehicle will have with a new tire size. for a rear wheel drive car, look at the rear tires). EV Calculator. 1524 X final drive ratio ÷ tire diameter. Now that you know that 28-inch tall tires reduce your final drive ratio, you can calculate the gearing need to match the performance of your original 26-inch tire/3. Now you must correct the chosen ratio for your specific tire size if it is other than the standard Cushman tire. * Drop Down Menu's may not work correctly on this page *. The tire size will allow you to calculate the RPM of the output shaft. Once you have chosen a specific ratio apply your tire correction factor and then use the following formula to determine the drive-out sprocket to use: Drive-out Sprocket teeth = (Big sprocket teeth * D) divided by (desired gear ratio. 10 gear ratio. 54 gear worked fine towing a relatively light 8,000 lb. com for the tire size calculator there as it has sizes in inches as well as metric ratings. Placing the example numbers in the corresponding fields you will get a Tire Height of 27. Old Tire Size: 31" New Tire Size: 35" Old Gear Ratio: 3. If the values are set to non-zero, then the calculator assumes you know what you are doing. Gear Ratio Calculator Tire Size gear ratio The gear ratio is the relationship between the numbers of teeth on two gears that are meshed or two sprockets connected with a common roller chain, or the circumferences of two pulleys connected with a drive belt. i M = n D / n F = (t I / t D) (t F / t I) = t F / t D (1b) where. I've spend a bunch of time trying to WAG (wild ass guess) my actual MPH when going down the road. Use the RPM calculator to determine what RPM your engine will run based on gear ratio, tire diameter, transmission and MPH. Enter the New Tire Height, Old Tire Height, & Original Rear Gear Ratio, Then Press 'Enter' Key Effective Ratio = (Old tire height / New tire height) * Original ratio Equivalent Ratio = (New tire height / Old tire height) * Original ratio New Tire Height Old Tire Height Original Ratio. Tire Revs Per Mile - This is the number of revolutions your tire will make in one mile. These calculators are designed to give the approximate engine RPM (revolutions per minute) based on data entered. Okay guys here is a calculator that I made on Excel. Divide the number of teeth in the front sprocket, or freewheel, by the number of teeth in the rear sprocket, or freewheel, and then multiply by the diameter of the rear wheel. A 55 aspect ratio means the tire's cross sectional height is 55% of it's width. This page is done using JavaScript and thus should be compatible with Netscape 3. By putting in different tire revs per mile, you can see the impact of different tire sizes. Hi! When you're done using this page, check out my new bicycle gear ratio comparison page!Thanks for visiting! To use the calculator below, select a wheel and tire size from the table or enter the wheel and tire size in mm in the "Dia. What power is required to pedal at different speeds in different gears with and without a headwind. 931 tire diameter. Ring-and-pinion selection made easy! Save yourself the headache and let us figure out your ring-and-pinion gear ratio! Just type in your info (example: 5000 RPM), press calculate, and you’ll get the right ratio without the guesswork. See effect on RPM in Gear/Sprocket matrix when changing sprockets. To calculate the size of the gear needed, use the formulas below. You can do this for yourself for the gears on your own bike using our gear calculator. In MFWD tractors, both the front and rear tires do the work. The ratio between the two is 1 to 1 which means they both rotate at the same speed, and the torque applied to the drive gear is the same at the driven gear. You can also do this to determine the effect of smaller tires on your final drive ratio. gear ratio guide for larger tires Whenever you change tire size from the original size or from one size to another, this will have a direct effect on power and driveability. The link above helps calculate tire size to gear ratio and what RPM range you will be in at speed. Listed are the expected RPM's at 60 MPH with a given rear end ratio and tire height. rpm / speed / gear ratio calculator. 50r18 Toyo Open country M/Ts. Finally, divide the result by 1,001 to find the number of gear teeth needed on the new driven gear. Gear Ratio Calculator. Hold your mouse over each field for additional instructions on how to use the calculator. The aspect ratio is the ratio of a geometric shape's sizes in different dimensions. Say you has a 3:00 ratio stock it will ask for old tire size in height and ratio 3:00 then it will ask new tire size 23 and tell you your new ratio with the tires is like a 2. Click "Calculate Differential Gear Ratio". Anyway, when I plugged the tires that I was looking at into the spreadsheet, the first ratio that I looked at was. Here's and example of how it will be listed and what each part means: For a car with 225/50VR16 tires:. On the other side of the same equation you can gear the same as your friends without Rubicon's and crawl even slower! Another factor to keep in mind is that the tire size listed on the tire itself is not always the actual size of the tire. While this unusual combination of millimeters, percentages and inches is a byproduct of the evolution of global tire. Wheel diameter can vary subject to tyre choice. How To : Choose Proper Gear Ratios. Follow Us On Twitter. A huge thank you to 1 Wild R/T for suggesting it. In order to calculate the engine RPM based on ring gear and pinion gear ratio, speed and tire height, this calculator makes the following assumptions: You may not be sure of the type of transmission you are currently using. The first number is the overall width in (mm). You would actually need to know the RPM that the clutch bell is turning to be completely accurate. Tech: Tires, Gears, MPH and RPM A common 4x4 application is an upgrade to larger-than-stock tires. The AEV ProCal will correct the tire size and gear-ratio values so the engine and transmission will properly calculate data (including automatic transmission shift points and ESP data) inside the factory software, ensuring the vehicle runs as intended. 73 turns means 3. The value of "Pi" is about 3. To use the Gear/MPH. CALCULATE IDEAL REAR GEAR RATIO. Try various combinations to come up with the best combination of gear ratio and tire size for your vehicle. A good way to calculate this is to multiply. 73 gear ratio requires 3. Gear inches are calculated as the Gear Ratio multiplied by the diameter of the wheel, 27 inches for a road bike (roughly equal to 700cc tires - tire size also is a factor, but this will be accurate to within a. Instead, the transmission is equipped with a VSS - vehicle speed sensor that is fed directly into the cluster, ecu, and cruise control module. He starts by teaching one how they "should" calculate their new gear ratio. In off-road racing, where tire diameters are relatively uniform, installing the same pinion and spur as another racer will net the same gear ratio. The effective multiplier of the stock M5 is (4. Try various combinations to come up with the best combination of gear ratio and tire size for your vehicle. How does the bike gear ratio calculator work? Our bike gear calculator can show the ratios for the range of chainrings and cogs teeth so that you can check your bike gear ratios and gear inches in different settings: Choose the minimal value of the teeth in the chainring. Second gear will have more torque than second gear with a lower rear end numerical ratio, but you will not be able to stay in second as long when the rear end gear ratio is increased. To calculate the size of the gear needed, use the formulas below. In this case, you need to secure one wheel (perhaps by lowering the tire onto the ground), then you can figure your gear ratio by rotating the airborne tire TWO full rotations and counting the number of times the pinion rotates. Ring Gear. Most modern passenger car and light truck tires feature size designations that indicate the tire's dimensions in a combination of metric, mathematical and English systems. Supports tire sizes in metric and inches. The tire size will allow you to calculate the RPM of the output shaft. Enter the value on the left, press Compute. Enter your gear ratio information, or use mine as the default. Drag Max RPM slider to adjust the range of the RPM and MPH Gauges. Unless driven gears with more than 45 teeth and / or drive gears with fewer than 15 teeth become available, it will be impossible without using a ratio adapter to have an accurate speedometer with rear end gear ratios lower (higher numerically) than 4. 2 inch diameter tires installed. PROFESSIONAL & SPORTSMAN. In mechanical engineering, a gear ratio is a direct measure of the ratio of the rotational speeds of two or more interlocking gears. You can alter the axle gear ratio, the transmission gear ratio and tire size to see the impact in real-time. you can see how much larger the old style is. Goodyear has a large tire catalog complete with all-season tires, winter tires, sport performance tires, and more. Larger wheels=more gear inches or more meters of development. I understand that an 8t pinion with a 24T crown yields a 3:1 gear ratio without considering tire diameter. Determine Ratio: Use this calculator when you know your final drive, but want to find your Gear Ratio for a given RPM & speed. Gear Ratio is the ratio of revolutions of the cranks to revolutions of the rear wheel. Here are a few calculators that may be useful in deciding tire size, gear ratios, and other stuff. for a rear wheel drive car, look at the rear tires). Plugging in the numbers you end up with: 3. 219 final drive. It is also the same letter that Volkswagen uses on the end of the ring & pinion part number to identify that gear ratio. The last two numbers of the part number is the number of teeth for the gear (Example 2538943 = 43 teeth). Choose the right Chevy model to narrow down your tire size results. The input here is for custom "Final Drive", "1st Gear Ratio", and "1st Gear Top Speed". Here's how to get to that end. Try our simple and easy to use Gear Ratio Calculator to quickly find the correct gear ratio for your differential. Metric sizes are listed after inch sizes. Multiply C by any gear combination FxB to get its gear-inches. From the wheel speed rpm, the size of the tire determines the final road speed of the vehicle. the most common i believe is the 3. 9 diameter, and my other tires which are 27. Axle Ratio - This is the gear ratio of your drive axle. 2 Updated: August 1, 2004. You can use my Gear Ratio Calculator to see how transmission gear ratios, final drive. Use this tool to compare two tire sizes. A range of options exists. Drag Racing Calculators,Calculators to find 1/4 mile ET and MPH, CID,Piston Speed,gear ratio,carburetor size,margin of victory,Engine calculator, Calculates relative horsepower, air density, density altitude, virtual temperature, actual air pressure, vapor pressure and dyno correction factor and more. It allows you to enter in gear ratios for each transmission speed, transfer case speed, differential ratio, and then tire size. Gear inches are calculated as the Gear Ratio multiplied by the diameter of the wheel, 27 inches for a road bike (roughly equal to 700cc tires - tire size also is a factor, but this will be accurate to within a. Gear inches is used mostly for comparing one drive train ratio to another and has little physical basis on a bicycle with derailleur gears. How to calculate gear ratio? There is 4 easy ways to help you. 42 New Gear Ratio = (New Tire Size/Old Tire Size) * Current Gear Ratio 3. Enter Diff + Gear Ratios and tire diameter, then drag RPM slider to calculate speed from RPM. Gear ratios 10 Answers. GEAR RATIOS CALCULATOR. One way to compensate for this is to swap out your differential gears. site: Tire Size Calculator = Scott Galaba's calculator on the SG Motorsports site: Gear/MPH Calculator - From f-body. Both of these issues will result in a loss of low end torque. Considering tire size as part of gear ratio is a rather useless approach IMO, as most racing is done in relation to a minimum tire size which is almost always used, or at least approached. PLEASE READ BELOW! Use the filter to make it easier to find the bike you want. They look cool and have the potential of being very functional, but they may also be robbing you of power/gas mileage. This calculator does not take into consideration any drive train loss, road. On a Rubicon, this means, going from 33's to 37's, you should go from 4. Power is transmitted from the transmission to rear end 1:1 in. This calculator can give you a good idea of max speed differences using different tire sizes, different gear ratios, or setups that rev a little different. Originally, gear inches represented the diameter of a high-wheel bicycle's drive wheel. A good way to calculate this is to multiply. Its come time for me to rep. Tire Growth-- At speed the tire will grow. road bicycle tire pressure calculators using Jan Heine 15% drop and Michelin chart methods. 85' 3: Differential gear ratio. 42 New Gear Ratio = (New Tire Size/Old Tire Size) * Current Gear Ratio 3. Instead, the transmission is equipped with a VSS - vehicle speed sensor that is fed directly into the cluster, ecu, and cruise control module.