XP Sprocket & Chain Chart

Gearing Chart spreadsheet

1:1 Clutch Ratio vs. Overdrive.

The gear calculator gives you the mph for 1:1 clutch ratio. Remember that this is where the belt climbs to about 7/8 of an inch from the rim of the primary. The only way the belt will or should go to the top of the primary "rim" is when you are able to do the highest mph attainable with your current drive ratio.
Example 21:45 @ 8150 rpms with 46.1 constant will offer up 82.5 mph.
@ 82.5 mph the belt will go up the primary clutch as high as approximately 7/8 from the rim. To get the belt to go up to the rim of the primary then the sled will have to go about 93mph (full shift overdrive)

Calculate Full shift overdrive (O.D. or o.d.)
For XP chassis you take the 1:1 mph and divide by .89. So then (82.5mph / .88) = 92.69mph

For MXZ/REV chassis you take the 1:1 mph and divide by .83. So then (82.5mph / .83) = 99.39 mph

When using the calculator, always good to calculate the mph for both shift ratios. 1:1 mph and the overdrive mph.
1:1 = 82.5
O.D. = 93

Clicky - Full shift Article (must sign up in forum to view - I have to keep spammers away)

Calculate a mile per hour - a "how to"

Bottom gear / Top gear = Gear Ratio
Example 43/27 = 1.59 ratio - Note that gears are generally discussed with mentioning the top gear first like "Twenty seven, fourty three"
Gears are displayed in text as 27:43 with a " : " to separate the values.
More examples, 44 / 24 = 1.83 ratio and then written and spoken as 24:44

Example Top Speed Calculation; 2008 mxzx 600RS
Engine rpms - 8400
Top gear 23
Bottom gear 49
Gear ratio (49 / 23) = 2.13
Clutch ratio - 1:1
Track pitch - 2.86"
Constant # - 46.1
Formula then is (8400 / 2.13) / 46.1 = 85.5mph

MXZX Rev chassis chain vs. Gear ratio

Example - 27:43(gears) = 1.59(ratio) = 76(Pitch chain)

27:43 = 1.59 = 76P
26:43 = 1.65 = 76P
25:43 = 1.72 = 76P
24:43 = 1.79 = 74P
...more to come

XP Chassis chain vs. Gear ratio

Example - 20:45(gears) = 2.25(ratio) = 102(Pitch chain)

20:45 = 2.25 = 102P
21:45 = 2.14 = 102P
20:45 = 2.05 = 104P



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Gearing Chart spread sheet

Constants for other ratios.
Need for me to get an excel spreadsheet person to help me fill in the blanks.

Ratio Teeth Pitch Constant

1 to 1	7	2.52	59.86
1 to 1	8	2.52	52.38
1 to 1	9	2.52	46.6
1 to 1	10	2.52	41.8
1 to 1	11	2.52	38.1
1 to 1	12	2.52	34.9
1 to 1	13	2.52	32.23
1 to 1	14	2.52	29.93
.83 to 1	7	2.52
.83 to 1	8	2.52
.83 to 1	9	2.52	38.6
.83 to 1	10	2.52	34.7
.83 to 1	11	2.52	31.7
.83 to 1	12	2.52	29.1
.83 to 1	13	2.52
.83 to 1	14	2.52
1 to 1	7	2.86	52.74
1 to 1	8	2.86	46.1
1 to 1	9	2.86	41.02
1 to 1	10	2.86	36.92
1 to 1	11	2.86	33.56
1 to 1	12	2.86	30.76
XP.9 to 1	7	2.86
XP.9 to 1	8	2.86
XP.9 to 1	9	2.86
XP.9 to 1	10	2.86
XP.9 to 1	11	2.86
XP.9 to 1	12	2.86
.83 to 1	7	2.86
.83 to 1	8	2.86	46.1
.83 to 1	9	2.86
.83 to 1	10	2.86
.83 to 1	11	2.86
.83 to 1	12	2.86
1 to 1	7	3	50.29
1 to 1	8	3	44
1 to 1	9	3	39.11
1 to 1	10	3	35.2
XP.9 to 1	7	3
XP.9 to 1	8	3
XP.9 to 1	9	3
XP.9 to 1	10	3
.83 to 1	7	3
.83 to 1	8	3
.83 to 1	9	3
.83 to 1	10	3
1 to 1	7	3.29	45.85
1 to 1	8	3.29	40.12
1 to 1	9	3.29	35.66
1 to 1	10	3.29	32.09
XP.9 to 1	7	3.29
XP.9 to 1	8	3.29
XP.9 to 1	9	3.29
XP.9 to 1	10	3.29
.83 to 1	7	3.29
.83 to 1	8	3.29
.83 to 1	9	3.29
.83 to 1	10	3.29

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