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Old 02-08-2004, 03:43 PM
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neurokinetik neurokinetik is offline
Mad Scientist
Join Date: Oct 2003
Location: Buffalo, NY
Posts: 901
Originally posted by 2fast4u
no no no you see that miniz owners thought that the xmod is way 2 slow maybe ill just pop in an x speed motor i was trying 2 prove that the only reason thet a miniz is faster than an xmod is the motor... every thing else doesnt seem 2 make a big differance.
The motor is not the only reason a Mini-Z tends to be faster than an XMod. It's the simplicity of the drivetrain that makes the difference. The Mini-z has a solid rear axle that passes through 2 ball bearings, and is driven directly by the pinion gear on the motor. The front wheels rotate on fixed axles. The XMod has so much more rotating mass. The center driveshaft alone is equivalent to the Mini-Z's rear axle, and then you add on all of the dogbones and universal joints, the extra gear between the motor and differential, and the fact that the front wheels are attached to rotating axles, even in 2wd. There is alot of motor power being used to drive all of that rotating mass. I know that motors I have created for the XMods have disappointed me as a result of this, while the exact same motors make my Mini-Z so fast it is almost uncontrollable.

Carbon fibre driveshaft is a good first step on the XMods. Next thing would be to address the dogbones and u-joints. We need strength, but we also need lighter weight, as we already have too much rotating mass. I'd like to see all of the axles, U joints, and dogbones made out of titanium and/or CF, depending on the location. The next step would be to use very high-quality ball bearings, like the TRC set that is forthcoming.

Lastly, there needs to be a solution to the pinion gear problem. Having to swap motors to change gears is unnacceptable, IMO. We either need removable pinions of the correct pitch to become available, or else somebody needs to create new spur gears that would work with any of the 48 pitch gears that are widely available. Then we need a motor mount that can be adjusted so that we have more than four gear ratios to work with. (I know you can use washers to shim the stock mount, allowing a few different ratios, but this isn't exactly ideal.)
-- It is by will alone I set my mind in motion...
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