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Conversion Charts and Other Good Info

Cross Reference Info

Tire Info

There are 3 different systems of tire measurment in use:

Inch System (i.e. 5.00 H 16 4PR)

5.00 = Section Width (inches)
H = Speed Rating
16 = Rim Diameter
4PR = Casing Strength (Ply rating)

Alphanumeric System (i.e. MT90-16 LRB)

M = Motorcycle Code
T = Tire Width Code
90 = Aspect Ratio (90%)
16 = Rim diameter (inches)
LRB = Load Range

Metric System (i.e. 130/90-16 67 H).

130 = Selection Width (mm)
90 = Aspect Ratio (90%)
16 = Rim diameter (inches)
67 = Load Rating
H = Speed Rating

Speed Rating - Speed (km/h) - Speed (mph)

B - 50 - 31 C - 60 - 37 D - 65 - 40 E - 70 - 43 F - 80 - 50 G - 90 - 56 J - 100 - 62 K - 110 - 68 L - 120 - 75 M - 130 - 81 N - 140 - 87 P - 150 - 94 Q - 160 - 100 R - 170 - 106 S - 180 - 112 T - 190 - 118 U - 200 - 124 H - 210 - 130 V - 240 - 149 Z - Over 240 - Over 149

Load Index - Load (lbs)

45 - 364 46 - 375 47 - 386 48 - 397 49 - 408 50 - 419 51 - 430 52 - 441 53 - 454 54 - 467 55 - 481 56 - 494 57 - 507 58 - 520 59 - 536 60 - 551 61 - 567 62 - 584 63 - 600 64 - 617 65 - 639 66 - 661 67 - 677 68 - 694 69 - 716 70 - 739 71 - 761 72 - 783 73 - 805 74 - 827 75 - 852 76 - 882 77 - 908 78 - 937 79 - 963 80 - 992 81 - 1019 82 - 1047 83 - 1074 84 - 1102
* 1 poumd is equal to 0.4536 kg.
The load index is an assigned number that corresponds with the load-carrying capacity of a tire.
Load/Speed Index developed in Europe in response to the need to control the safe performance of tires at standardized speeds.

Tire Size - Rim - Overall Width - Overall Diameter

90/90H19 - 2.15 - 3.7 - 25.4 90/90H21 - 2.15 - 3.7 - 27.3 100/90H19 - 2.50 - 4.3 - 26.1 100/90V19 - 2.50 - 4.3 - 26.3 110/90H18 - 2.50 - 4.5 - 25.9 120/70R17 - 3.5 - 4.7 - 23.7 120/70ZR17 - 3.50 - 4.8 - 23.9 120/80V16 - 2.75 - 4.7 - 23.8 120/80V18 - 2.75 - 4.8 - 25.9 120/90H16 - 2.75 - 4.9 - 26.3 120/90H18 - 2.75 - 4.9 - 26.5 120/90V18 - 2.75 - 4.8 - 25.9 130/70VB18 - 3.50 - 5.4 - 25.4 130/80V18 - 3.00 - 5.4 - 25.4 130/90H16 - 3.00 - 5.0 - 25.4 130/90V16 - 3.00 - 5.2 - 25.0 MT90H21 - 2.15 - 3.8 - 27.8 140/70V18 - 4.00 - 6.1 - 25.7 140/80VB16 - 3.50 - 5.9 - 24.8 140/90H16 - 3.50 - 5.8 - 25.6 150/70VB18 - 4.00 - 5.9 - 26.2 150/80H16 - 3.50 - 5.9 - 25.4 150/80V16 - 3.50 - 5.9 - 25.4 160/80H16 - 4.00 - 6.4 - 26.1 160/80VB16 - 4.00 - 6.8 - 26.1 170/60R17 - 5.50 - 6.6 - 25.2 170/60VB18 - 4.50 - 6.9 - 26.0 170/60ZR17 - 5.00 - 7.0 - 25.0 180/55VB18 - 5.00/5.50 - 7.0/7.1 - 26.1/26.3 180/55ZR17 - 5.50 - 7.2 - 25.0 180/60R17 - 6.00 - 7.1 - 25.0 180/70HR16 - 5.00 - 7.1 - 25.9 190/50R17 - 6.00 - 7.7 - 24.5 190/50ZR17 - 6.00 - 7.8 - 24.6 200/60VB16 - 5.25 - 7.9 - 25.8 230/50x15 - 7.00 to 8.00 - 9.5 - 29.3 250/40x18 - 9.00 - 10 - 25 250/40HR18 - 9.00 - 9.9 - 25.9 300S19 - 2.15 - 3.5 - 26.4 300S21 - 1.85 - 3.1 - 27.2 325S19 - 2.15 - 3.4 - 25.9 500S16 - 3.00 - 5.2 - 26.4

* Note: Measurements are based on the given rim widths. A rough rule of thumb: Each additional 1/2" of rim width will be approximately 1/4"

Metric Size - Alphanumeric Size - Inch

80/90 - MH90 - 2.50/2.75 (Front) 90/90 - MJ90 - 2.75/3.00 (Front) 100/90 - MM90 - 3.25/3.50 (Front) 100/90 - MM90 - 3.75/4.00 (Front) 110/90 - MN90 - 3.75/4.25 (Rear) 120/80 - ... - 4.25/4.50 (Front) 120/80 - MP85 - 4.50/4.75 (Rear) 120/90 - MR90 - 4.25/4.50 (Front) 120/90 - MP85 - 4.50/4.75 (Rear) 130/80 - ... - 5.00 to 5.10 (Rear) 130/90 - MT90 - 5.00 to 5.10 (Front) 130/90 - MT90 - 5.00/5.10 (Rear) 140/80 - ... - 5.50/6.00 (Rear) 140/90 - MU90 - 5.50/6.00 (Rear) 150/80 - MV85 - 6.00/6.25 (Rear) 150/90 - MV85 - 6.00/6.25 (Rear)

New Metric - Old Metric - Inch

60/100 - 90/80 - 2.50/2.75 (Front) 70/100 - 90/80 - 2.75/3.00 (Front) 80/100 - 100/80 - 3.00/3.25 (Front) 80/100 - 80/90 - 2.50/3.60 (Rear) 90/100 - 110/90 - 3.60/4.10 (Rear) 100/100 - 120/80 - 4.00/4.10 (Rear) 100/100 - 130/80 - 4.00/4.50 (Rear) 120/100 - 140.80 - 5.00/5.10 (Rear)

Gear Ratios for Final Drive Pulleys

Transmission Pulley Stock 5-speed Big Twins come with 32-tooth pulleys. Smaller 29, 30, and 31-tooth pulleys provide stronger acceleration, while larger 33 and 34-tooth pulleys reduce engine speed for smoother cruising.

Rear Wheel Pulley Smaller pulleys will reduce the engine speed for smoother cruising. Larger pulleys will raise the engine speed for stronger acceleration.

Primary Drive Ratio 1985-1993 - 1.54 (24/37 tooth combination) 1994-2003 - 1.44 (25/36 tooth combination)

Stock Rear Chain Applications (Length)

FL,FLH (1955-1979) - 530 x 102 FLT,FLHT (1980-1984) - 530 x 110 FXR (1981-1983) - 530 x 110 FXST,FXWG (1984-1985) - 530 x 102 FX,FXE (1971-1984) - 530 x 102 XL,XLH,XLCH (1958-1985) - 530 x 110 XL883 (1986-1991) - 530 x 106 XL1100 (1986-1987) - 530 x 106 XL1200 (1988-1990) - 530 x 106 ------------------------------------- (Extra Length Applications 530 x 120)

Conversion Tables

Fractional Inch to Decimals of Inch and Millimeters

1/64 = 0.0156 = .3969 1/32 = 0.0313 = .7938 3/64 = 0.0469 = 1.1906 1/16 = 0.0625 = 1.5875 5/64 = 0.0781 = 1.9844 3/32 = 0.0938 = 2.3813 7/64 = 0.1094 = 2.7781 1/8 = 0.1250 = 3.1750 9/64 = 0.1406 = 3.5719 5/32 = 0.1563 = 3.9688 11/64 = 0.1719 = 4.3656 3/16 = 0.1875 13/64 = 0.2031 7/32 = 0.2187 15/64 = 0.2343 1/4 = 0.2500 17/64 = 0.2656 9/32 = 0.2812 19/64 = 0.2968 5/16 = 0.3125 21/64 = 0.3281 11/32 = 0.3437 23/64 = 0.3593 3/8 = 0.3750 25/64 = 0.3906 13/32 = 0.4062 27/64 = 0.4218 7/16 = 0.4375 29/64 = 0.4531 15/32 = 0.4687 31/32 = 0.9687 1/2 = 0.5000 33/64 = 0.5156 17/32 = 0.5312 35/64 = 0.5468 9/16 = 0.5625 37/64 = 0.5781 19/32 = 0.5937 39/64 = 0.6093 5/8 = 0.6250 41/64 = 0.6406 21/32 = 0.6562 43/64 = 0.6718 11/16 = 0.6875 45/64 = 0.7031 23/32 = 0.7187 47/64 = 0.7343 3/4 = 0.7500 49/64 = 0.7656 25/32 = 0.7812 51/64 = 0.7968 13/16 = 0.8125 53/64 = 0.8281 27/32 = 0.8437 55/64 = 0.8593 7/8 = 0.8750 57/64 = 0.8906 29/32 = 0.9062 59/64 = 0.9218 15/16 = 0.9375 61/64 = 0.9531 31/32 = 0.9687 63/64 = 0.9843 1 = 1.0000

Table of Equivalents

To Convert ===> Into ===> Multiply By
Into <=== To Convert ===> Divide By

Acre-Feet - Cubic Meters - 1233 Acres - Square Meters - 4047 Atmospheres - Feet of Water - 33.9 Atmospheres - Inches of Mercury (Hg) - 29.92 Atmospheres - PSI (lbs per Sq. Inch) - 14.7 BTU - Foot Pounds - 778.3 BTU per hour - Watts - 0.2931 BTU per Minute - Horsepower - 0.02356 --------------------------------------------------- Centimeters - Inches - 0.3937 Cubic Centimeters - Gallons (US Liquid) - 0.0002642 Cubic Centimeters - Litres - 0.001 Cubic Feet - Cubic Inches - 1728 Cubic Feet - Gallons (US Liquid) - 7.48052 --------------------------------------------------- Cubic Inches - Cubic Centimeters - 16.387 Cubic Inches - Cubic Feet - 0.0005787 Cubic Inches - Gallons (US Liquid) - 0.004329 Days - Seconds - 86,400 Degrees (Angle) - Radians - 0.01745 Feet - Metres - 0.3048 Feet - Miles - 5280 --------------------------------------------------- Feet of Water - Atmospheres - 0.0295 Feet of Water - Inches of Mercury (Hg) - 0.8826 Feet of Water - PSI (Lbs per Sq. Inch) - 0.4335 Feet per Minute - Miles per Hour - 0.01136 Feet per Second - Miles per Hour - 0.6818 Foot-Pounds - BTU - 0.001286 --------------------------------------------------- Foot-Pounds per Minute - Horsepower - 0.0000303 Foot-Pounds per Second - Horsepower - 0.001818 Gallons (US Liquid) - Cubic Feet - 0.1337 Gallons (US Liquid) - Cubic Inches - 231 Gallons of Water - Pounds of Water - 8.3453 Horsepower - BTU per Minute - 42.44 --------------------------------------------------- Horsepower - Foot-Pounds per Minute - 33,000 Horsepower - Foot pounds per Second - 550 Horsepower - Watts - 745.7 Hours - Days - 0.04167 Hours - Weeks - 0.005952 Inches - Centimeters - 2.54 Inches - Millimeters - 25.40 --------------------------------------------------- Inches of Mercury (Hg) - Atmospheres - 0.03342 Inches of Mercury (Hg) - Feet of Water - 1.133 Inches of Mercury (Hg) - PSI - 0.4912 Inches of Water - PSI - 0.03613 Litres - Cubic Centimeters - 1000 Litres - Gallons (US Liquid) - 0.2642 --------------------------------------------------- Micron - Inches - 0.00004 Miles (Statute) - Feet - 5280 Miles per Hour (MPH) - Feet per Minute - 88 Miles per Hour (MPH) - Feet per Second - 1.467 Ounces (Weight) - Pounds - 0.0625 Ounces (Liquid) - Cubic Inches - 1.805 --------------------------------------------------- Pints (Liquid) - Quarts (Liquid) - 0.5 Pounds - Grains - 7000 Pounds - Grams - 453.59 Pounds - Ounces - 16 PSI - Atmospheres - 0.06804 PSI - Feet of Water - 2.307 --------------------------------------------------- PSI - Inches of Mercury (Hg) - 2.036 Quarts - Gallons - 0.25 Square Feet - Square Inches - 144 Tons (US) - Pounds - 2000 Watts - Horsepower - 0.001341

Fastener Info

American Standard Course (Size - Thread/Inch - Tap Drill Size)

#1 - 64 - 53 #2 - 56 - 50 #3 - 48 - 47 #4 - 40 - 43 #5 - 40 - 38 #6 - 32 - 36 #8 - 32 - 29 #10 - 24 - 25 #12 - 24 - 16 1/4 - 20 - 7 5/16 - 18 - F 3/8 - 16 - 5/16 7/16 - 14 - U 1/2 - 13 - 27/64 9/16 - 12 - 31/64 5/8 - 11 - 17/32 3/4 - 10 - 21/32 7/8 - 9 - 49/64 1 - 8 - 7/8

American Standard Fine (Size - Thread/Inch - Tap Drill Size)

#0 - 80 - 3/64 #1 - 72 - 53 #2 - 64 - 50 #3 - 56 - 45 #4 - 48 - 42 #5 - 44 - 37 #6 - 40 - 33 #8 - 36 - 29 #10 - 32 - 21 #12 - 28 - 14 1/4 - 28 - 3 5/16 - 24 - 1 3/8 - 24 - Q 7/16 - 20 - 25/64 1/2 - 20 - 29/64 9/16 - 18 - 33/64 5/8 - 18 - 37/64 3/4 - 16 - 11/16 7/8 - 14 - 13/16 1 - 14 - 15/16

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