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Old Nov 08, 2005, 01:26 PM
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Randy Due's Avatar
Chandler, Tx. USA
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What's The Proper Procedure For Changing Spur Gear In Cobri Gearbox?

I need to change ratio in my Cobri. How do you remove and replace the spur? I have a puller for the pinion, but thought I would ask before trying the spur. Thanks.

Randy
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Old Nov 08, 2005, 01:39 PM
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mexico's Avatar
NJ
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A pinion or gear puller is - as the name implies for pulling off the pinion gear from the motor shaft. The spur gear on the Cobri Gearbox is simply presss fit. Firmly but carefully apply even pressure as close to the center of the gear as you can with two thumbs and it will come off.
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Old Nov 08, 2005, 02:55 PM
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Chattanooga, Tennessee, United States
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Quote:
Originally Posted by Randy Due
I need to change ratio in my Cobri. How do you remove and replace the spur? I have a puller for the pinion, but thought I would ask before trying the spur. Thanks. Randy
I take the shaft and spur out of the gearbox, slip the shaft between the jaws of a vice (just open enough to allow the shaft between) so that the spur rests flat on the top of the vice. Tap lightly on the 'front' end of the shaft and gently drive it down through the spur. Fit the new spur by placing it, front face down, on the top of the vice and tap the shaft through from the rear.

Cheers, Phil
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Old Nov 08, 2005, 08:37 PM
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Thanks! Any green Loctite on the spur needed?

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Old Nov 08, 2005, 08:57 PM
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Chattanooga, Tennessee, United States
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No, it goes on over the splines.
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Old Nov 08, 2005, 10:19 PM
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Chandler, Tx. USA
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Okay. Thanks.

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