Blew up XR ITS Upper
#21
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From: San Bernardino



I was able to get the helmet off, but cannot get the driveshaft out, check out those splines the pinion gear was on. I can’t remember what the gimbal bearing looked like, but I think the inner portion is pushed in.
#23
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From: San Bernardino
Just to check I’m not crazy. Since I have the lower off, if I rotate it and the prop shaft turns 1 revolution, and the shaft that goes up in the upper rotates 1 and almost 1/4, that means I have 1:24 gear ratio,,,,right? If so , I’m surprised I can turn 32p and 30p props.
#25
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From: ankeny,ia.
Just to check I’m not crazy. Since I have the lower off, if I rotate it and the prop shaft turns 1 revolution, and the shaft that goes up in the upper rotates 1 and almost 1/4, that means I have 1:24 gear ratio,,,,right? If so , I’m surprised I can turn 32p and 30p props.
Last edited by JaayTeee; 09-08-2018 at 11:42 PM.
#29
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From: San Bernardino
I guess what nobody is saying is, since the upper is not 1:1 , you can’t figuer out gear ratio by turning the vertical shaft in the lower and count rotations, you need it together as a unit and turn the driveshaft, and count rotations.
#30
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From: KY
No it can be done, by rotating the lower 10 times. Your rotating 10X because it becomes more obvious, then working with small degrees
As example
Upper gears 19/16 = 1.187
Lower gears 15/19 = 0.789
Calculation 1.187/0.789 = 1.504 ratio
So rotate and count
1.26 lower 17/18 = 0.944 10X = 9.44
1.35 lower 15/17 = 0.882 10X = 8.82
1.50 lower 15/19 = 0.789 10X = 7.89
As example
Upper gears 19/16 = 1.187
Lower gears 15/19 = 0.789
Calculation 1.187/0.789 = 1.504 ratio
So rotate and count
1.26 lower 17/18 = 0.944 10X = 9.44
1.35 lower 15/17 = 0.882 10X = 8.82
1.50 lower 15/19 = 0.789 10X = 7.89
Last edited by AllDodge; 09-09-2018 at 02:30 PM. Reason: removed divide part



You're going to need a bigger slide hammer! Those splines are impressive.